DR. SHAPIRO: We are now in that part of our session where we are dealing, in at least a very initial fashion, with requests from President Clinton, which I read to all of you this morning. To reread just a part directly from the letter: "This week's report of the creation of an embryonic stem cell that is part human and part cow raises the most serious of ethical, medical and legal concerns. I am deeply troubled by this news of experiments involving the mingling of human and nonhuman species. I am, therefore, requesting that the National Bioethics Advisory Commission consider the implications of such research at your meeting next week and to report back to me as soon as possible." This is a paragraph from the more complete letter, which I read this morning. But that's the part of it which we're addressing now. The second part of the request we will address over time.
I have asked Dr. Brinster of the University of Pennsylvania to respond to any questions that we might have regarding any aspect of the science that is related to this and the nature of the experiments. He will at least answer to the best of his ability any questions that we have. And then, of course, we can see where that discussion leads us. And then, we, of course, will have our own discussions subsequent to that. And as I said, we'll do this in a Q&A format. This is what Brinster proposes at the first. So let me turn to Eric, first of all, to pose the first few questions that we have, and then we'll turn to the commissioners to see what questions they have. I would ask the commissioners if they have a question to please identify themselves so that Dr. Brinster will also know who it is that's asking the question. Let me then turn to Eric Meslin. And let me just ask Dr. Brinster if he can hear us.
DR. BRINSTER: It's very difficult, but I can hear you.
DR. SHAPIRO: We'll do the best we can. Let me ask everyone to talk as directly as they can into their microphone.
DR. MESLIN: Good afternoon, Dr. Brinster. It's Eric Meslin. We spoke yesterday on the phone, and thank you very much for being available by teleconference today. There have been a number of questions that have been put together that we hope you will be able to respond to. The first is: What is the state of the art, to the extent it is known, regarding production, including isolation and culture, of human stem cells?
DR. BRINSTER: Well, the recent publication I think the state now of human embryonic stem cell research, what was published in Science last weekend, will probably appear in the next national proceedings of the National Academy of Sciences. And in one case, apparently certainly pluripotent embryonic stem cells of human origin were produced from embryo outposts. And in the second report, by Gerhardt, it's likely that similar cells were produced from fetal germ cells. These are two well-established techniques in mouse embryology and the generation of these pluripotent and totipotent, in fact, stem cells. So that much we know from the published reports: that many tissues can develop from the stem cells. The final proof of totipotentcy is not likely to be achieved, because the final proof is the generation of germ cells in another animal that arises in part from stem cells but they certainly are widely pluripotent now. Does that answer your question?
DR. MESLIN: I think we will allow the statements to stay, and if commissioners wish to jot down their questions back for Dr. Brinster, we'll continue on. The next question: How are nonhuman cells used if the desired product is a human stem cell?
DR. BRINSTER: All right. Can you repeat the question? I'm not sure I understood it.
DR. MESLIN: There are two versions. I'll read you this version. The first is: How are nonhuman cells used if the desired product is a human stem cell?
DR. BRINSTER: I couldn't hear the connector. How are stem cells used?
DR. MESLIN: Let me rephrase it in a different way.
DR. BRINSTER: Thank you.
DR. MESLIN: Or why, would be another version. What research has been done that would help determine if a nonhuman oocyte might be used to produce a human stem cell?
DR. BRINSTER: Oh, okay. Published research is not very direct. It's been known for many years that oocytes in general reprogram nuclei in a number of species, including the mouse. That technique was used to generate the clone animals, and to demonstrate that complete repro does occur. I'm not aware that any published information has appeared showing that other species will reproduce from another oocyte. There is the New York Times report that is a narrative description of what was done, but not published.
DR. MESLIN: Could you say something about whether we know if the resulting product is totipotent or only pluripotent?
DR. BRINSTER: I don't even know if there is I know that there is a claim that someone has put a foreign nucleus in and made stem cells in a cow oocyte, but that has not been published, or, in the second instance, that's required in Science that it be repeated by someone. So, there is no proof positive that this had taken place that I'm aware of.
DR. MESLIN: As a more general matter, though, could you help us understand the difference between totipotency and pluripotency?
DR. BRINSTER: Well, the easiest way I think of probably four levels of potency or ability in a cell, and the first one is totipotent. That's the ability to make any cell, including germ cells, and the last critical part, including stem cells. Pluripotent cells are the next level, and this level can produce more than one type of motor cell. It may produce many types, including everything but one type, and that one type is generally the germ cell, which is the most difficult to regenerate in those terms. So the pluripotent cells may make only blood cells, or it may make only sperm cells, or it may make only skin cells, or only intestinal cells, but it makes several types in most cases, so it's plural.
Multiprogramming is another term. The third level of cell, differentiating cells, becoming some particular type of cell, either growing from one mouse cell. Their fate is generally determined, but they have changing characteristics. And the fourth type, a fully differentiated cell that will change no more, like on the surface of the skin or the final cell on the intestinal epithelium or a nerve cell. And the type that you're interested in today is totipotent and pluripotent. And the difference is the totipotent will make germ cells, and make every cell; the pluripotent makes many cells, but cannot make every cell.
DR. MESLIN: Is there uniform agreement or consensus within the scientific community, be it in the animal research community as well as the human research community, with the use of those terms? Is there any confusion or ambiguity that you think is existing?
DR. BRINSTER: I don't think there is very much ambiguity, especially between totipotent and pluri. Some people call pluripotent, multipotent. And in some of the old literature people use pluripotent and multipotent without knowing whether they could make every cell.
DR. MESLIN: Could you say something about the resulting product, that is to say, the product that we've been discussing here this afternoon that you've just referred to, that was reported just recently, if the cell as an organism is a true chimera or not?
DR. BRINSTER: Repeat the question, please.
DR. MESLIN: Would the resulting product, the cell or organism itself, be a true chimera?
DR. BRINSTER: Well, the word "chimera" has many definitions, too, depending on the background and who's using it, in Greek mythology it's one thing, and in biology another. But in terms of the question, are you referring to the reported paper about putting a human nucleus in a bovine oocyte?
DR. MESLIN: Yes.
DR. BRINSTER: That would be considered a chimera by scientists?
DR. MESLIN: Yes.
DR. BRINSTER: I think most scientists would probably not regard it as a chimera because I think most scientists think in terms of the old Greek definition of a chimera, or the more recent biologic definition, where there is a mixture of cells in the body. I don't think, for example, that people regard transgenic animals as chimera, where there is an actual mixing of genes of several species, one or two genes of one species put into a mouse, for example. I don't believe I have ever heard anyone call that a chimeric animal. So I don't think such an animal, that if an animal were generated from an oocyte, say of a mouse, and the nucleus of a dog, would be considered a chimera.
DR. MESLIN: Just so we're clear: what would you refer to it as?
DR. BRINSTER: I think it would be a dog, because I think no one knows what's going to happen, or if it, in fact, has been achieved. But if it did happen, it's likely that the nucleus would it seems probable, one possible outcome, that the nucleus of the species transplanted into the oocyte would actually multiply would change the proteins, and the proteins would become, for example, the proteins of a dog, if you were in a mouse oocyte. And it's likely that mitochondria would be transplanted with the nucleus, and it would be very difficult to transplant nuclei, I think, without mitochondria. Those nuclei might be placed in the nuclei of a mouse oocyte.
DR. MESLIN: Thank you very much. Those are sort of the initial kickoff questions to get the Commission oriented. Now I'll let Dr. Shapiro....
DR. BRINSTER: Well, the committee should realize that the mitochondria the proteins that make the mitochondria are coded by genes in the mitochondria, but also by genes in the nucleus. So it's likely, then, that there has to be a match between those two in order for the mitochondria to survive, that some mito must be made that can survive in order for the cell to survive. Is that clear?
DR. SHAPIRO: Yes. This is Dr. Shapiro. I have one question, but let me turn first to the other commissioners to see if they would have some questions for you. Professor Charo?
PROF. CHARO: Hi, this is Dr. Charo, and let me just tell you I'm from the University of Wisconsin with a background in law rather than science. Dr. Brinster, I wonder if you'd answer two questions. First, assuming you have fused a human differentiated somatic cell with a cow oocyte, does this fused cell have the ability to divide in an organized fashion through embryonic and fetal stages such that it could become a baby?
DR. BRINSTER: I think the question was if you fused a human nucleus to a bovine oocyte, would it be able to develop fully.
PROF. CHARO: Correct.
DR. BRINSTER: I can't answer that, and I don't think we have any published information to answer that. It's possible that it could. But it's also possible that it would die, that other things that are unknown make it work.
PROF. CHARO: Second question: Would such a fused cell divide initially in a way that is virtually identical to that of a normal human embryo so that it could in theory be used as a substitute for normal human embryos for the purposes of early embryo research?
DR. BRINSTER: I think that's possible, but not yet proven that it will occur. I think that's possible, but it hasn't been done yet as far as I'm concerned.
PROF. CHARO: Thank you.
DR. SHAPIRO: Thank you. Other questions from members of the commission? Yes: Larry Miike.
DR. MIIKE: This is Larry Miike. I'm a public health person. Given the various scenarios about creating tissues and organs, etc., what's the state of the environment in which such cells would have to be nurtured in, for example, making a skin cell versus making a whole organ such as a liver or a kidney?
DR. BRINSTER: It's very difficult to hear the question. I don't know if the pickup is bad. I can hear parts of it, but I couldn't hear the whole thing.
DR. MIIKE: I guess, to make it simple, what's the state of technology in the environment in which the cells would have to be nurtured between making cells versus making organized organs?
DR. BRINSTER: Okay. I think I understand: the question is what's the state of the technology to convert a stem cell into an organ. Is that correct?
DR. MIIKE: That's right.
DR. BRINSTER: I wonder if there's a microphone down there that each person could use, because it's difficult for the questions. But I think I have that question correct, and I would say that the technology is under development and has been for a long time regarding mouse embryonic stem cells. The work on mouse embryonic stem cells goes back more than 25 years that people have been trying to understand development from these and direct them to specific tissues. Now certainly the pace has increased in the last five or 10 years, and so some cells can now be directed toward muscle and perhaps to the hematopoietic system to make blood precursors. So that in a couple of instances where a couple of tissue cells can be made, in other words converted from a pluripotent cell with wide capacity that is a stem cell, known as an embryonic stem cell to a stem cell for the blood system or for a muscle cell. And in those cases it's been shown that they will participate in the normal system of a mouse. No organ, to my knowledge, has been made. And that would be a very complicated technology to evolve.
DR. SHAPIRO: Thank you. Tom Murray?
DR. MURRY: Good afternoon. Let me first establish that you can hear me.
DR. BRINSTER: I couldn't hear that.
DR. MURRAY: Good! You answered my question! Let me try again. Can you hear me, Dr. Brinster?
DR. BRINSTER: Yes. I can hear you.
DR. MURRAY: This is Tom Murray from Case Western Reserve University. I have two questions. The first is what information, if any, do we have from studies with animals involving use of oocytes from one species and the nucleus from another to tell us whether those organisms are viable and what sort of identity they would have should they be viable. That is, what species would they be if they were viable?
DR. BRINSTER: Well, the answer to the last question, I don't know; if they were viable there is, I think, no doubt they would be the species of the nucleus, because the cell would be programmed to become compatible with the nucleus. The cell would not be the cell cytoplasm would not be able to change the species of the nucleus. All of the coding information is in the nucleus. And in regard to what information we have, I have to say that there's no new information of which I'm aware that shows this can be done. There's old information where you can show that the nucleus of one species is changed when you put it into another species, but as far as I know there's no published report indicating you can generate an early developmental stage such as a blastocyst that is, three or four days' development by using the nucleus of one species and the cytoplasm of another species. There are rumors in the scientific community that people are trying it. But I have not seen anything publicly, and in science that has to be the first step.
DR. MURRAY: Thank you for that answer. Let me try one additional question.
DR. BRINSTER: Okay.
DR. MURRAY: Do you see any compellingly important scientific research that could be done by the use of, say, a bovine embryo and a human nucleus, that could not be done by using embryos, by using, rather, oocytes and nuclei from other species, but not involving either human oocytes or nuclei?
DR. BRINSTER: I'm not sure...was the question, is there any advantage to using oocytes, nuclei of humans rather than the nuclei of other species in the bovine? Is that the question?
DR. MURRAY: Right. Is there any compellingly interesting science that could be done at this point that would require us only to use human DNA rather than, say, DNA from another mammal?
DR. BRINSTER: I think that initial experiments can be done in laboratory animals or farm animal species to show the feasibility of this approach and also to work out details of how it can be done and what would result if it works. As I said, I think there's a little doubt if it will work, that what will result is an animal of the nuclear species. But I think that if you want to use it in humans and also on other primates as models for human disease, that you have to eventually do experiments in nonhuman primates and with human cell nuclei. And aside from the basic science research and understanding of developing programming for the structuring of tissues, one of the great values of this embryonic stem cell technology is the potential to make some tissues for replacement in human disease.
DR. SHAPIRO: Thank you. Carol Greider?
DR. GREIDER: Hello. This is Carol Greider from Johns Hopkins University. I'm a molecular biologist.
DR. BRINSTER: Yes.
DR. GREIDER: I have two questions. The first is how many cell divisions do human cells go through before the zygotic genome would take over?
DR. BRINSTER: That's difficult to say because those types of studies haven't been done in the human. But as a general principle, the mammalian genome begins to express a few genes almost immediately after fertilization. Certainly by the two-cell stage the mouse embryo is expressing genes. And then progressively more of the zygote genes are expressed as the embryo proceeds. But by the blastocyte stage I would certainly guess that in every species the embryonic genome is in control, probably beginning maybe at the eight-cell stage. The shift is pretty dramatic at the eight-cell stage in many factors of embryonic development. That's about two to three days after birth.
DR. GREIDER: Yes. Thank you. And then the second question relates somewhat to that and it has to do with the possibility, if one were talking about making, going through implantation and the possibility of immune rejection, what species' antigens would you expect at the stage of implantation on a cross-species oocyte?
DR. BRINSTER: Well, I think that if you have put the nucleus of a dog sample into a mouse then you would have to transplant that oocyte back to the dog. It would not grow in the mouse, is my guess, because the species difference is too great. But if it went back into the dog, I would expect that it would be accepted, because we know that chimeras exposed to several strains of mice are not rejected in utero. The immune system is polarized as the embryo develops. I guess that's an appropriate term for the committee. Does that answer your question?
DR. GREIDER: Yes, thank you.
DR. SHAPIRO: Other questions? Excuse me. Professor Charo again.
PROF. CHARO: Dr. Brinster, could you please comment on the reported presentation by Neil Furst last January in Boston on his experiments using fusions of mammalian species not involving humans? Specifically the report his reported speculation that these fused cells would not in fact be viable after a period of days.
DR. BRINSTER: After he transplanted the nucleus into the oocyte?
PROF. CHARO: Correct.
DR. BRINSTER: Well, I think it's like many things, and as I indicated in the beginning, these are only narrative reports in the newspaper. We do not know whether this system would work. And I assume that it will be published soon and that other groups will then try to report it, where groups that are reported to be working in this area will in fact actually publish rather than in a science journal. And then it can be repeated. So until that's done, I think none of us really knows what would happen. It is possible that they would die after a few cleavage divisions. Most of the questions I've responded to have implicitly assumed or wondered what would happen if in fact they did live. Whether they will live is unproven.
PROF. CHARO: One last question, if I may? For medical applications in the human, in the future, people have suggested that cloning one's own tissue to generate stem cells for personal cell therapy would be important. Would you see the easy availability of bovine oocytes in which to, with which to clone one's own cells as a viable way of pursuing this and avoid the need to obtain human eggs from live women?
DR. BRINSTER: Well, I think the interesting or potentially important aspect of the proposed procedure, where you transplant a nucleus into the oocyte, is that you could use the nucleus from the person or individual that needed the tissue and therefore circumvent the immunological problems that would arise just using a general embryonic stem cell of human origin. Because there will be immunological problems, just like with organ transplant. But if you take the individual's own cells and put them into an oocyte, I'm not sure that bovine oocyte is the oocyte of choice. It just happens to be the one that's reported. And so if you transplant it into another oocyte then you have the potential of making embryonic stem cells that would be compatible with that individual, which is a major improvement in technology and would not require immunosuppression. And to use those cells to replace bone marrow, or muscle cells, or whatever.
DR. SHAPIRO: Other questions from commissioners? Yes, Professor Scott-Jones?
DR. SCOTT-JONES: My name is Diane Scott-Jones. I'm a professor of psychology at Temple University. I'm a developmental psychologist. And my question is regarding the possible use of this scientific work. You've mentioned that one possible use is to cultivate tissues for the replacement of diseased tissues in humans. Is there any other possible scientific use of this work that you anticipate?
DR. BRINSTER: I think embryonic stem cells.... I assume you're talking just about the human embryonic stem cells?
DR. SCOTT-JONES: Yes.
DR. BRINSTER: Well, I think that probably most scientific questions regarding developing differentiation from stem cells and other tissues could be addressed in the classic way by using mostly primitive species or lower species, like the mouse, and then eventually looking at primate species. So I see probably the medical aspect here as extremely important. But there are also always the small differences between species in terms of regulation of tissue development, which you do not anticipate. So just as most experimentation can be done first in the mouse regarding the logical understanding of the immune system, and then into primates and so on, I think the same rules exist here, where most of the information is obtained as simply, with the most economical means, in lower forms, and then, eventually, some work has to be done with the human.
DR. SCOTT-JONES: I have one more question. We read that there's been an application for a patent for these cells. Do you have any opinion on the appropriateness of that?
DR. BRINSTER: No, I can't say that I have an opinion on it. I don't know very much about law, and there are many people that know ethics better than I do, so I really have to say I don't have an opinion.
DR. SHAPIRO: Thank you. Professor Murray?
DR. MURRAY: Hi, it's Tom Murray again. You've said a few things about the fate of mitochondria, of the oocyte mitochondria, and what would happen. Do we have any really solid scientific data about the likely fate of those oocyte mitochondria, or is this mainly a kind of well-informed speculation about their likely fate? Is it possible, for example, that mitochondria in the receptive oocyte might take the same signals to divide and multiply and go with the daughter cells as the mitochondria from the nuclear species?
DR. BRINSTER: Yes, that is possible, but we don't know much information. It's been a topic of interest. In fact we tried very early, maybe 15 years ago, to transplant mitochondria, and several of my students have subsequently done experiments transplanting mitochondria to look at how long they last. At least one of these students was successful in showing that when you transplant mitochondria to the fertilized egg, they are still present in the blastocyte stage. But it's a very difficult experiment, and it's not clear how many are present. We know also that there is considerable similarity among, or conservation among, the proteins of mitochondria in related species. But we do not know the absolute answer to the question that you ask. For example, is the dog close enough to the cat, or is the human close enough to the cow, so that the genes, so that the number, so that the genes that are present in the nucleus will support the development and interact with the genes that are present in the mitochondria from two different species? For example, will the human nuclear mitochondrial genes provide proteins of sufficient similarity so that they will interact with mitochondrial gene proteins to construct hybrid mitochondria? We do not know the answer to that. That can be worked out to a great deal of perfection by using animal species, and it's, as with anything in biology, you really have to do the experiments to know the answer.
DR. SHAPIRO: Thank you. Professor Greider?
DR. GREIDER: Yes, this is Carol Greider once again. Following on the mitochondrial question, in the case where instead of transplantation one uses cell fusion to fuse a somatic cell with an oocyte, one would presume that you would also have then a mixture of mitochondria. Might you then expect that the same species' mitochondria, that is the mitochondria that had the same species as the nucleus, would then win out in the competition? Or do you have any expectations in this scenario, where there's not transplantation?
DR. BRINSTER: When cells are fused both nuclei are present, though initially both types of mitochondria could be supported. I'm not aware of any studies; I can't remember exactly studies that determine whether one type of mitochondria is eliminated. It seems to me that they are, but I cannot vouch for that because it's not in my field, and I cannot recollect for certain. But it's a good question whether when you fuse two cells from two different species, like human and mouse, which is done many times, which mitochondria persist. That may be in the literature.
DR. SHAPIRO: Thank you.
DR. BRINSTER: But also it will be very complicated to determine, because quite frequently the chromosomal complement on these cells is abnormal, so that some chromosomes for both species are retained. And that is not the situation in which we're interested. I don't know that looking in the literature will answer the question that you really want, and that is whether any mitochondrial genes persist into the adult as a nuclear transplant into an oocyte.
DR. SHAPIRO: Thank you. Any further questions? If not, then Professor Brinster, let me once again thank you very much for your willingness to join us in this rather unusual way. I very much appreciate your patience, and thank you very, very much for your help.
DR. BRINSTER: You're welcome. Good luck in your meeting.
DR. SHAPIRO: Thank you.
DR. BRINSTER: Goodbye.
DR. SHAPIRO: Let me say a word about how we're going to proceed. We only really have, I hope we'll only use right now, about another half an hour to discuss further aspects of this. My intention is to appoint a bucket or something, with that old phrase that we used to use, to actually draft a letter back to the President this evening, which we can approve or not, as the case may be, tomorrow morning. If we don't get that far, then we'll approve it by e-mail or something else like that in the next day or so. I do feel an obligation to get back sometime this week and as early as tomorrow, but that depends on just where our discussion takes us. So that's what I'm intending to do. All of you can wonder which of you is going to get appointed to this, but that will be a matter of mutual agreement. I'll do that at the break. But in any case, let's just open up the floor for discussion. I think the focus of discussion ought to be on what is the nature of the kind of response we can make. Given, obviously, there's a huge number of unanswered questions here, what could we do that would both be helpful in clarifying in an initial way some of the issues here? While obviously we're going to have to postpone other aspects of the issue until we can deal with this in greater depth. The thing that we absolutely don't want to do is answer beyond our capacity or knowledge at this stage. We can't do that, and I'm sure no one wants to do that. So let's just open it up for discussion and suggestions about how we might structure a response, what kind of things we might include, and so on. Tom?
DR. MURRAY: Well, we could certainly reemphasize something that we said in our report on the phone, that maybe that technology like this, and this does involve somatic cell nuclear transfer, it would be wrong to attempt to make a child from this technology. We can say that we believe this falls under the prohibition we recommended with respect to trying to create a child by cloning. That would be one that's not a response to all the issues raised by it, but it's just one thing we can reemphasize.
DR. SHAPIRO: Diane?
DR. SCOTT-JONES: I would like to see us comment on the appropriateness of this kind of information appearing in a major newspaper before scientific articles are available for review and comment. It seems to me that this isn't the way we want science to proceed, that science is very cautious, that there's a high value placed on replication and on careful peer review. And I would like to see the letter and make some comment about the process of disseminating the information.
DR. SHAPIRO: Eric, then Bette.
DR. CASSELL: Well, the President expressed concern, and so did other people reading it, about the danger of this phenomenon of the transplantation of two different species, including the human being. I would like to hear something from David and Carol about that danger, and if in fact there is a danger, what would have to happen before the danger is realized, and so forth, so that we directly respond to the first of the questions.
DR. SHAPIRO: I could just add on to that, and then maybe we can turn to see if either David or Carol can help us understand this better, and then we'll go to Bette's question. The President does refer to the mingling of human and nonhuman species, reacting not as a scientist, but it seems to me that in one way that's been going on for a long time that is introducing, as I understand it, human material into nonhuman animals in one way or another to do various things. Whereas I think that's not I don't know, but it didn't seem to be what the President quite had in mind. So as you try to respond to Eric's question, I just wanted to add another uncertainty to your question I have in my mind to that. So maybe, I don't know, David or Carol? Which one of you would like to have anything to say regarding Eric's question?
DR. COX: I'm happy to start. I really do think we start past the concept of mingling proteins, because that's what recombinant DNA is and we do that for a living, so we're past there, all of us are. So let's start by mingling cells. But that's been going on for a very long time, too since the 1960s. And it doesn't just happen experimentally with scientists, but it actually happens inside different organisms, too. But obviously not one cell from one organism, one cell from another organism. That happens only with scientists. Hamster cells were fused with human cells all the time. They create hybrid cells. And the knowledge about what happens when you do that, which cell takes over the answer is it's complicated. There aren't any really defined rules. But the point is that those are cells, and cells aren't organisms, all right? Cells are cells. Those cells don't turn into anything but cells. They don't turn into living, what we would call organisms, defined as organisms. So for me the question here, what to say to the President is, that there's nothing new here in the context that cells from different organisms are being used that's part of ongoing science, and it has been for 20 years. What's new is the concept that cells between organisms are fused and could turn into an organism, that is, a living being. And the answer to that is, nobody has any idea, because as Dr. Brinster said, we don't know. And based on what we know about fusing somatic cells from different organisms, we really don't know, because there's not even any standard prediction that you can make from that. So to me, it's that this isn't if we knew for a fact that fusing, putting a human cell in a bovine oocyte, would not lead to anything past two-cell division. That is to me not a new issue, because you cannot make an organism that way.
I'm not saying there aren't ethical issues involved there. For me, the issue is whether you can make an organism or not. We do not know the answer to that. And so what do we do about that? That, to me, is the $64,000 question. But it's not the idea, not the visceral response that everyone gets, including myself, when you talk about mixing a cow cell with a human cell. That's not where the action is. So those are my sort of differentiating points. And the difficulty is knowing whether you put that human nucleus into a cow or, as far as I'm concerned, you put any other species into any other species' oocyte, whether that can actually divide and make a living organism. We don't know the answer.
DR. CASSELL: May I follow up, just quickly?
DR. SHAPIRO: Yes, sir.
DR. CASSELL: Does that mean, David, that leaving out this, you know, this spectacular nature of the newspaper, and that if this was your line of work, you would use another species first? Not human-cow but whatever mouse-cow?
DR. COX: Yeah, but let's be really candid. Because of the differences between species, you will never know whether you put that human cell into another oocyte, whether it will lead into an organism or not. Okay? You may have some ideas about it, but you won't know.
DR. SHAPIRO: Carol?
DR. GREIDER: I agree with everything that David said. What is new here is not the issue of mixing cells but rather, what people are concerned about is, can this form an organism? And that's where the concern is, and that's back to where we were for the cloning report. If these are just cells, however, that's where the importance of the human comes in, because the second charge and the second part is going to be to look at the issue of human embryonic stem cells and what one can then do medically with those differentiated cells from the pluripotent cells. And there are a lot of really exciting possible therapeutics that we pointed to, as a matter of fact, in the cloning report, that might be useful. And so that's an answer as to why human because all of those medical possibilities you would have to have human cells for. And so I don't think that those issues, which are sort of a secondary issue, that if we agree that we're just working with cells then the issues become somewhat different, and I think we're going to deal with those in a separate issue.
DR. SHAPIRO: Larry? Let's see, Bette, I'm sorry.
MS. KRAMER: That's okay.
DR. SHAPIRO: Larry?
DR. MIIKE: I guess I'd look at it in a slightly different way. I think what we should concentrate on is a short report, because the second part of the letter really asks us to take a look at the broader issues a straightforward description of what these techniques are and what the attempt would accomplish. I would look at this and say, for example, on the human cloning issue toward a baby, is there any advantage to doing this over using human cells? For one thing. Doesn't seem to be any unless you want to make thousands of you the same, I mean, you know, just an implausible scenario. And then, if we're not dealing with that, I think because some of the issues we raised were that, if we were looking at our old cloning report, we were talking about dangers to women who have to be the source of the oocytes. That would not be present here. So I would look at what are the end results that we're aiming for, and do they raise the same kinds of issues that we did in our original cloning report? And I think we should just let it lay that out on a very factual basis. And I think that this report, since we need to be short, really should be spending most of its time just sort of explaining what exactly we're talking about, because the reports in the newspapers give a sense that it's a really alarming situation, and maybe it's not.
MR. STEVEN H. HOLTZMAN [on speaker phone]: Hello? Hello?
DR. MESLIN: Steve, is that you?
MR. HOLTZMAN: Yes, I can barely hear you.
DR. MESLIN: Very good. You've joined us. Welcome. It's Eric. We'll try to speak directly into the microphones. The pickup is not always easy. This is Steve Holtzman, as you know a member of the Commission who was unable to be here today, and I asked him to join us for this part of the conversation.
DR. SHAPIRO: Let me ask these questions are so simple I hesitate let me go to Bernie first. I'll save my questions. I'm sorry, Bernie.
DR. LO: Trying to follow up on the lines of thought that other people have started, it seems to me that we do have a framework, both from our cloning report and other previous reports, and I think the points that were made about how we don't really know what's going on because there's nothing published and the details aren't there, and the points David and Carol made that what's unique here is the possibility of having a totipotent, pluripotent or even totally potent cell that might be capable of developing into an organism makes it different than other types of protein or cell commingling. But if we think about two of the purposes to which these cells might be put, one would be implantation with development to a mature organism. And as Tom suggests, we probably want to say that raises a lot of grave concerns. In our cloning report, we sort of set out recent concerns about safety and concerns about ethics. It seems to me again, here, that general framework is useful. That from what I heard Dr. Brinster say, there are a lot of concerns about is this going to work, what's going to happen, and have we done enough, even taking into account David's point that eventually, if we're going to, if we want to use it for human stem cell transplantation, we're going to use human nuclei, should we be doing some preliminary work on other transspecies transfers into oocytes? Is it really premature to start thinking about either transplantation or certainly implantation until we've resolved some of these safety questions? Then, I guess, there are these sort of, I don't know what you want to call them, philosophical concerns, or just uncertainties, about what would it mean, assuming this worked and if it were safe, what would it mean to have an organism, or to have a cell that had the potential, perhaps if implanted, of developing into an organism that had the nuclear DNA of a human being and either the mitochondrial DNA of another species or, if you did a couple of transfers that was in the letter we talked about somehow you've got the human DNA in there as well. And we haven't even begun to think about what that would mean; isn't that the point of what David and Carol were saying? This is sort of a new conceptual lead, and maybe we want to say that we certainly need to start to think out both the safety issues and the conceptual issues before we just say, "It's a green light, go ahead, it's no problem." But I think the framework we developed in terms of safety, scientific concerns, and then also sort of moral concerns is useful.
DR. SHAPIRO: David, then Jim.
DR. COX: Yeah, so you helped me a little bit Bernie, because now I'm just going to not consider for a moment the ethical considerations and simply consider some scientific considerations. So one of the things right now is that it's very difficult to get human oocytes from purely scientific points of view. And so to study issues about making pluripotent stem cells, irrespective of making babies, irrespective of ever talking about implanting it. As a scientist, one might think that it's easier to basically do the fusions between bovine oocytes and human cells. In fact, from a purely logistics point of view, that's probably correct. That's not even human subjects work, right? Because as we've already said, there are all kinds of fusions that go on right now between human cells and mosquitoes, okay? There have been fusions between human cells and carrots! Right? So that fusion between a bovine oocyte and a human somatic cell? Scientists wouldn't even bat an eyelash from a scientific point of view. Now I think that most of the public doesn't realize that these kinds of cell-cell fusions go on, so I just want to emphasize that. But I would say that as a scientist, if I wanted to understand these issues of reprogramming cells, which is what this is all about from a scientific point of view for many scientists, is that mixing things between species confounds the science tremendously. For the reasons that I said, that we can't predict who's going to win and in fact, okay, that each cell contributes different amounts of stuff, which makes it difficult to do controlled experiments. So I'll just say, this is what I do for a living. I make these kinds of hybrid cells, and it's been disappointing to me over the last 25 years that I haven't been able to learn more about what controls them. So as a scientist, in my area of expertise, I would not choose to do an interspecies experiment first. That doesn't mean that one couldn't learn something from that at a particular time, but that, I don't think, is the preferred way to do the experiment. So one could say, Bernie, from a purely scientific point of view, this is the best way to go. But I would argue against that. And that's irrespective of any of these other issues. But just to emphasize again that I would really like to make clear that fusing cells of different species is not new, and it's been going on for a very long time.
DR. SHAPIRO: Bernie, do you have another comment before we go on?
DR. LO: I just wanted to ask David to clarify his comments that it's not new to fuse the nucleus from a human cell and the cytoplasm of the oocyte from another species. My understanding is that ordinarily those experiments do not lead to a pluripotent or a totipotent cell. Now is that because the experiment wasn't designed that way, or that they failed? You sort of said what's new here is the potential to develop into an organism. So how can you explain to us how what's being proposed or talked about here is different from these experiments you've been talking about?
DR. COX: One of the ways that it's different is that an oocyte and this is also an extremely important point an oocyte isn't just another cell. An oocyte is a very special type of cell. In fact, without an oocyte, to my knowledge, you don't make an organism. Think about that. It's that there's no other somatic cell, okay, that you can do without except an oocyte. Ultimately, even if you have a blastocyst, we put a somatic cell in, that had to have an oocyte to start with. So the oocyte is an extremely special cell. As far as we know, that's what it takes to have an organism. You can't do it without an oocyte. So that's definitely different.
DR. LO: It's unique that they used an oocyte as the host?
DR. COX: Well, but I don't know that it's unique because other people have. It's not unique that they've used an oocyte, because there have been other experiments, as was reported in the human embryo report, where they basically fertilized hamster oocytes with human sperm. So this isn't the first time that somebody has put a human nucleus into an oocyte of a different organism. But I do think what's unique about it is the concept, and what people are struggling with from the ethical matter, not from the scientific point of view, is what would happen if that actually could develop into an organism? From a scientific point of view we don't know whether that could develop into an organism, even if it was able to divide once, twice, three times, we simply do not know. But I would just say that the pure science, not even talking about it turning into an organism, looking at other issues, that I believe is a start. It's not the preference from a scientific point of view to do the mixed species first.
DR. SHAPIRO: Thank you. I have a number of people on my list now, starting with Jim, then Dr. Charo, then Arturo. Jim, you wanted to comment?
DR. CHILDRESS: Just a matter of observation, given our experience on the cloning report. I just want to make sure that we don't fall into a sharp division between safety and ethics because I think the safety concerns are, of course, ethical concerns, but there are a lot of other ethical concerns as well.
DR. SHAPIRO: Thank you. Alta?
PROF. CHARO: Before I say anything, should I go on, let me just go on the record about the fact that back at Wisconsin I've had conversations with Jamie Thompson before he began his research about the separation of his research from Federal funding, and have been a member of a committee after his research was completed that was looking at it from the point of view of the university's interests. A question to Carol, and then a comment. Carol, you had asked Dr. Brinster when it is that the zygotic genome takes over, and I didn't understand what that meant or why that was significant.
DR. GREIDER: It was partly a lead-in to my second question, if we're getting to the, if people are going to be asking us is it possible for you to create a human with this bovine oocyte and a human nucleus, presumably you would have to implant that into some organism. And I was thinking that the antigens on the bovine cell would make it be rejected if you were to implant it into a human, and therefore it would not be possible to make it a human. That's what I was thinking.
PROF. CHARO: Thank you. The comment actually in some ways it's more of a question is probably directed mostly at David and Carol. I'm not sure. It seems to me that part of the analysis that one would want to develop for the President could focus on what this fused cell is most like that we already know. Is it most like two nongametic cells that are fused, or is it most like a regular human embryo, or is it most like something else? And as I listen to these things I'm particularly intrigued by your comments about uncertainties. I find myself thinking that the question is, would it be inappropriate to try to do that? Would it be most appropriate to say that this is something that is entirely new as a phenomenon and can't be analyzed by analogy to other entities and can't be conveniently slotted into existing schemes of either ethical discourse or regulatory treatment?
DR. COX: My view is, unfortunately, that's exactly the situation. I mean I think that this isn't simply another fusion of two somatic cells, nor is it an embryo because we don't know that it even divides. Unfortunately, I believe it's closer to an embryo than it is two somatic cells, and I say that based on my view that the egg is a special type of cell.
PROF. CHARO: But its viability is severely in question, which is the key characteristic of embryos that drives all the debates about embryos.
DR. COX: So it's new, Alta, is what it is.
DR. BRITO: This question is for David and Carol to clarify something here that was reported in the New York Times, and I recognize this has not been necessarily scientifically proven. But what is the significance? They've discussed that at some, at one point the combination of bovine oocyte cytoplasm with the human nucleus becomes primordial and this is what is key in terms of it being able to form a stem cell that further divides. Is this something that's new in hybrid research, the fact that it can revert to a primordial state?
DR. GREIDER: I think that "pluripotent" is the word. Pluripotent, and that's what we were hearing from Dr. Brinster that you can get certain cell types, which is what the two papers that you were just given are about these pluripotent human embryonic stem cells that were reported, which will be our other issue. So the thought is that if you can take this bovine B human mixed cell type and differentiate it, you can get these pluripotent cells out, that would then go on to form something which would be mostly a human tissue type that could be used in medical research, muscle cells, neurons. And so the point is that you can make this pluripotent cell type from that initial fused oocyte.
DR. BRITO: Right. So the primordial reversion of this hybrid, is that something new?
DR. GREIDER: No.
DR. COX: No, that's been around.
DR. GREIDER: The thing that's new here is that it's two different species. The other thing that we're talking about is what we dealt with in cloning, which is taking a human nucleus and putting it into a human cell, and you can get those same cell types out there. The difference here is the convenience. It's easier to get these oocytes from cows than it is from humans.
DR. BRITO: No, I understand that. But David was discussing earlier the fact that cells from different species have been -- this has been done for a long time, but I had never heard of different species being able to combine with the nucleus into an oocyte of different species within the cytoplasm.
DR. GREIDER: He's talking about cells from different species.
DR. BRITO: Yes.
DR. GREIDER: Somatic cell types -- you take two different somatic cells that are growing in culture and fuse those and study their properties. And that's David's area.
DR. COX: That's what cloning is, so that's what we talked about-- transfer cloning. I'd like to make it clear that it is unclear that this has happened between the cow -- the bovine oocytes and the humans. There is to me no evidence one way or another, because I don't get my science from the New York Times.
DR. BRITO: Right, but that's....
DR. COX: I will say, though, that it's not new, the idea of being able to take cells from different species, one of which is differentiated and one that isn't. So, for instance, a muscle cell of one species can take a lipocyte from another species and you can basically turn on muscle genes. So this idea of reprogramming by taking different types of cells at different levels of differentiation isn't a new one.
DR. BRITO: No, I understand. Thank you.
DR. SHAPIRO: I do want to tell the commissioners that Michael West is here. He performed this experiment we're all talking about, or referring to, and thinking about -- and have limited knowledge about. I think he was here. Is he still sitting in the back there? All right. And I only mention that to see if anyone has a question they would like to ask Dr. West,.I'm sure he would be -- I'm not sure he may wish to answer.
DR. COX: Well, I would very much like to know what was done.
DR. SHAPIRO: Dr. West, would you want to just come and sit over here until there is a microphone available, so you won't have to stand?
DR. COX: And I don't think that publication is the way one gets one's science.
DR. MICHAEL WEST: Right.
DR. COX: But oftentimes people describe to one another what the experiments were before they're published.
DR. WEST: Right.
DR. COX: And that hasn't happened here. So if you're willing to do that it would be extremely informative.
DR. WEST: Let me just say parenthetically here that we at Advanced Cell Technology had this debate internally as to whether we should proceed with this research as you know, this was done back in '95/'96, before Dolly or not do anything, or whether we should proceed with the work and do more work and then publish the data; or -- and, actually, I proposed it would be best for us to disclose publicly what had been done, even though it's preliminary, and even though obviously we'd get the criticism that this is not available for public review. But the data actually is published. It's in the European patent filing, and it is preliminary data. But we felt that -- at least I felt that it would be best for us to set a precedent here. This is a very controversial area, obviously, involving nuclear transfer, cultured embryonic cells, and so on. And right or wrong -- and we certainly will bear the criticism but we felt -- I felt that it would be better for us to disclose this data and talk about it openly rather than setting a precedent of saying, "Look, let's have science go on behind locked doors, and then do experiments out of the public view." And that is why we chose to release this information publicly in a premature state.
DR. COX: Dr. West, excuse me. Can I ask one question?
DR. WEST: Yes.
DR. COX: When you take human cells and you put them into nucleated bovine oocytes, how many times do the cells divide?
DR. WEST: Well, the research that was published in the European patent filing was some 50 nuclear transfers, largely oral mucosal epithelial cells, but also blood lipocytes and fibroblast inter-nucleated bovine oocytes, again because we are a bovine cloning company and have large access to bovine oocytes. And again, as was mentioned earlier, the long-term thought here would be to supply a surrogate oocyte that could be humanized, so as to have human mitochondria as an accessible, inexpensive, and we believe humane alternative to animal source oocytes for nuclear transfer. Some 50 nuclear transfers were performed. In the patent filing we gave an example of one blastocyst formation. Most -- as with all nuclear transfers, all but 1 or 2 percent go to full-term blastocysts. We had similar numbers with the human nuclear transfer leading to one blastocyst, which when put in culture led to cells that flourished for a short period of time, and that had an indistinguishable morphological criteria of embryonic stem cells. As you know, there are numerous morphological characteristics: small cytoplasmic-to-nuclear ratio, prominent nucleoli refractile boundary, and so on. And we filed, based on that -- we had subsequent data and did replicate those results.
DR. COX: But if I understand that by nucleating bovine oocytes, putting in a human somatic cell of different types, then it's possible, and in fact you, on more than one occasion, had blastocyst development.
DR. WEST: Yes, that's correct.
PROF. CHARO: May I follow up on that?
DR. SHAPIRO: Yes, Alta.
PROF. CHARO: And then what happened? Did you actually stop any further development past the blastocyst stage, or did development -- normal development stop on its own?
DR. WEST: Well, the goal of this technology was to find a surrogate source of oocytes to deprogram human somatic cells for human therapy. Therefore, when the blastocyst stage was reached, the blastocyst was put in a culture, as is typical, to derive embryonic stem cell cultures.
DR. SHAPIRO: Thank you. Diane?
DR. SCOTT-JONES: Would there be a way that you could make available to us a copy of your report that you said you filed?
DR. WEST: Yes: it is in the public domain, and I can easily make that available yet today if helpful.
DR. SHAPIRO: That would be fine. If you would just send one copy to our office in Washington, we can take care of distributing it. We would really very much appreciate that. I don't want to -- I don't know what Dr. West's schedule is like, but since he's here, if there are other questions now would be a good time to ask, if there are additional questions. Yes, Trish.
PROF. BACKLAR: You said that you did replicate this. Can you tell us how many times you replicated?
DR. WEST: I know that it was replicated once. I am a little fuzzy on another experiment. I believe at least a blastocyst was achieved. I'm not certain about the embryonic stem cells.
PROF. BACKLAR: Were the numbers equal in the second replication with the attempt at one blastocyst?
DR. WEST: I believe they were roughly equivalent. And again, I would emphasize, these are approximately the numbers we see. We perform roughly 1,000 nuclear transfers a week in the effort to make cloned cattle that have produced pharmaceuticals in their milk. And those are roughly the numbers we get with bovine cloning as well.
PROF. BACKLAR: Okay. May I ask you one more thing? And that is, how are you funded for this research?
DR. WEST: It's entirely a private biotechnology firm.
DR. SHAPIRO: David?
DR. COX: Yes: one more question, moving to the evidence for human embryonic cells.
DR. WEST: Uh-huh.
DR. COX: So for those -- and you mentioned the morphologic characteristic. How many times were they passaged -- actually, I have three parts to this. How many times they were passaged; if an analysis was done to see if their chromosome content was a normal diploid human chromosome; and third, were they ever able to be cloned from an individual cell? That is, once you have the stem cells, could you create the clones from individual cells?
DR. WEST: At the time these experiments were performed, the cells were analyzed only for these morphological characteristics. There were no antibodies in the laboratory to do state-specific embryonic anigen markers and other markers that are characteristic of ES cells. I think if we had those regions available, I'd perform those experiments. I think we probably would have had a publishable amount of data. That data was not available. Chromosome analysis was not done. However, the removal of the genomic -- nuclear genomic material is confirmed by staining under ultraviolet light. So we actually observe the removal of the nucleus, and, of course, the implanting of the human cell. We think it's highly unlikely that this was anything other than human cells, based on that.
DR. SHAPIRO: Alta?
PROF. CHARO: Dr. West, you mentioned humanizing the bovine mitochondria, if I heard you correctly.
DR. WEST: Yes.
PROF. CHARO: I wonder if you could explain what that means and what its significance would be.
DR. WEST: Well, we haven't talked about this just until recently for our own intellectual property reasons, but the goal here was not to mix species. And I think the President has justifiable concerns about mixing the species, as has been I think debated in the last 25 years from recombinant DNA technology all the way to the present day. The goal was to make a new technology available, which is based on human embryonic stem cells on the one hand and nuclear transfer on the other, and actually marrying the two together. So the thought would be, if we have a patient afflicted with a disorder where we need transplantable cells, we could take a body cell, de-differentiate it, use it in therapy, and it would be histocompatible. The remaining problem, of course, would be the source of the oocytes. And, in addition to the problem of sourcing the oocytes, we have quality control issues. If indeed this technology moves forward, sourcing human oocytes in large quantities would be a nightmare for the Food and Drug Administration and for biotechnology doing quality control on 1,000 or 100,000 different women would just be most impractical. And so the thought would be, if we could source oocytes from a cloned animal, all would have the same genetic background, all could be kept in confinement. They could be well characterized and potentially, as we said, engineered by reverse nuclear transfer, for instance, to have bovine oocytes with human mitochondria. We believe it's possible. I could actually lay out how that strategy would be performed. And then when nuclear transfer would be performed, we'd have a fully human embryonic stem cell. I think that's an important point, which was not brought forward in any of the previous discussions today.
PROF. CHARO: So you would then -- you would be taking the enucleated bovine oocyte and turning it into a culture medium and nothing more?
DR. WEST: That's essentially right. As you know, we culture therapeutic cells today in the presence of bovine serum, which contains cow proteins. This is essentially no different from that. We believe that we would be eliminating all bovine genetic material, and simply incubating the human somatic cell in these embryonic bovine proteins to de-differentiate the cell, unlocking this pattern of gene expression, which would allow the cells then to differentiate into pathways currently inaccessible in medicine.
PROF. CHARO: And do you have anything at all by way of what could become a handout that explains the reverse nuclear transfer process that would humanize the mitochondria?
DR. WEST: Actually, I have some diagrams I brought with me today, which I'd be glad to pass around, which diagrammatically lay out this procedure, and I think make it clear how it could be performed.
DR. SHAPIRO: Okay. Well, if you could pass that out, I'm sure that would be helpful and instructive. But I think there may be some more questions. Diane?
DR. SCOTT-JONES: I have a question about whether you have thought through any of the possible ethical issues that arise with the research that you're doing. You've already said that you are not engaged in any of the kinds of things that President Clinton mentioned in his letter that might be possibilities of the notion of mixing species. But what do you see as the ethical issues that you face in this research, and what are your thoughts on how you'll resolve them, or how you'll create in the public the view that you are behaving ethically?
DR. WEST: I appreciate that question. That's a very good question and a very challenging one. By way of background, I was the founder of Geron, the company that made the -- that sponsored the work on the embryonic stem cell work. And there I formed an Ethics Advisory Board with members of the biomedical ethics community, in part because I believe that it's important for biotechnology to be self-circumspect in this area. I think as we inevitably in the coming years have more and more sophisticated technologies, which raise more and more red flags, I think it's absolutely critical to keep public trust and to have open and honest discussions. Forgive me for telling a personal story, but I read a newspaper editorial by an individual who wrote that science should stop so that ethics can catch up. And my personal ambition in biomedical research is to communicate to people in public policy and in biomedical ethics, so that, simply, ethics can walk hand in hand with science and science does not have to stop, because there is so much to be done in so little time. I do think there are -- these are very complex issues, as I mentioned, combining nuclear transfer technologies with cells that for all practical purposes are totipotent, the human embryonic stem cell. The only truly totipotent embryonic stem cell is the mouse, that we know of, and, possibly chicken, in that these cells can become everything, including the germ line. Cultured bovine and porcine and rhesus monkey and human appear to be ES-like in that, as you'll see in our patent, we describe ES-like cells as meaning cells that have -- they are potentially totipotent, but they -- not in the case of human, but in the case of bovine and porcine when attempts are made to make them go germ line they do not form germ line tissues but are shown to make every other somatic tissue. So for all practical purposes, we believe these human ES cells -- at least the ES-like are potentially totipotent, or at least so close the only cell would not be germ line. So the ethical issues involved in such an important cell and what it means in human medicine, and also in many other respects the nuclear transfer to make those cells, and then on top of that the genetic modification of these cells creating cells in human cells and tissues that are transgenic. Many of these technologies have not existed before, and our hope is that we can simply have very intensive dialogue in the years ahead. And frankly, our hope was by announcing this preliminary data we could stimulate such discussions. We are not currently working in this area of technology waiting for consensus, and we would love to be able to feel comfortable with knowing the guidelines as to how we could proceed.
DR. SHAPIRO: Carol?
DR. GREIDER: I just have one question with regard to what you were just saying. The term "totipotent," as opposed to "pluripotent " you were referring to these cells as ES-cell-like, and yet you used the term "totipotent." And I thought that we just established from Dr. Brinster that cells which do not form germ line are considered pluripotent. Is there a discrepancy here?
DR. WEST: Well, there is a bit of a discrepancy. Pluripotent is often used for the bone marrow stem cell, which can become many cells, the lipocytes and the granularcytes and so on, but not a neuron, not a myocardial cell. It's true that we could call the cultured human ES cells pluripotent because of their ability to form every cell in the body. Presumably, the only cell in question being the germ line, I question whether pluripotent is a good enough designation that you're right to be absolutely accurate, have not demonstrated their totipotency. Pluripotency certainly has been demonstrated.
DR. GREIDER: So that the information that you're going to give us from the patent application describes them as totipotent?
DR. WEST: ES-like, or potentially totipotent, I think, would be ideal from my perspective.
DR. LO: I have a question, which is both a definitional question and a conceptual question. As I understand it from Dr. Brinster's comments, he defines a totipotent cell as one that is capable of being differentiated into all cell lines, including germ cells. I take it that's in vitro, in the laboratory. Do we know what happens if you were to try to plant a punitive totipotent cell into the uterus of the species from which the DNA was taken?
DR. WEST: Yes. Generally, those experiments are the chimera experiments where you take a blastocyst embryo and then inject into it cultured embryonic stem cells and it forms a hybrid chimeric animal, sort of like a zebra, or half -- made of some -- parts of the body are made of one type of cell, and the other part made of the other. And you usually then sort out animals where the cells have contributed to the germ line to get animals that have been entirely genetically engineered. But in terms of your question, okay, are these cells totipotent? Does that mean that they are capable of forming a pregnancy if injected into the uterus? All of the evidence suggests that they are not. That's an important point. These cells form a part of an animal, or indeed an entire animal if injected into a blastocyst where there is a trophectoderm, a sphere of cells that form the placenta. These cells, the embryonic stem cell for a mouse, which we say is totipotent, or presumably the ES-like cells from other species, will not form a pregnancy if injected into a uterus. They are not totipotent in that sense, that they can lead to a pregnancy. Totipotency only refers to their ability to form the many different cell types in proper conditions.
DR. SHAPIRO: Perhaps I could ask a question that may be going over ground you've already covered. If so, I apologize. The question I have in mind is, in order to develop these various techniques given the objectives here, is it -- do the next steps on the scientific agenda over the next year, or two years or whatever it would be, really need to deal with human material, or is there a series of animal studies that you would choose to do first? And you perhaps have answered this question. If so, I apologize, but that wasn't clear to me. I'm worried about the next steps in the scientific agenda to achieve the objectives you're interested in.
DR. WEST: It's certainly true that research can proceed with purely animal studies as opposed to human. However, I think that, as you know, in the United Kingdom a distinction has been made in nuclear transfer work between therapeutic cloning and reproductive cloning. And I think it may be the truest course in most of the human interest to allow human cell therapies to develop unencumbered at a maximum rate for lack of fear that our attempt here is to clone a human being. I think it's clear that there are straightforward research objectives here: to make important stem cells for human medicine that would not run the risk in any way of facilitating the cloning of a human being.
DR. SHAPIRO: Thank you. Any other questions? Yes?
PROF. CHARO: A quick clarification, Dr. West. We just all received a handout called "Comparison of Methods for Generation of Human ES Cells." This is not the diagram about reverse nuclear transfer.
DR. WEST: That's correct.
PROF. CHARO: Okay. That's a different one that will be coming around eventually?
DR. WEST: That diagram just compares the human ES cells as described by Dr. Thompson and Dr. Gerhardt....
PROF. CHARO: Right.
DR. WEST: ... versus an autologous ES cell made by nuclear transfer.
PROF. CHARO: Have you been working on the humanization of mitochondria for the past three years, or is that an extremely recent area of interest?
DR. WEST: Well, it's a long-term area of interest, and we have not begun any work really, but we would like to proceed in that area.
DR. SHAPIRO: Diane, Carol, and Tom.
DR. SCOTT-JONES: This is just a question to ask you what this is so we'll know how to identify it -- I mean the source of it should we reference you what the source of it is?
DR. WEST: That's from Advanced Cell Technology, correct.
DR. SCOTT-JONES: I'm sorry?
DR. WEST: That's from Advanced Cell Technology, to clarify how the technology that we're describing compares with the science paper and the PNAS paper that just recently came out. The first diagram on the left describes the approach of making human embryonic cell therapies by nuclear transfer using a surrogate oocyte. For instance, a bovine oocyte that's been humanized to have human mitochondria. The second diagram describes the sourcing of embryonic stem cells that are not autologous. "Allogeneic" is the terminology meaning from another human being, essentially another embryo from in vitro fertilization. And therefore there are issues regarding histocompatibility. And the third describes cells sourced from the gonadal ridges of developing fetuses, the embryonic germ cell or embryonic stem cell as described by Johns Hopkins.
DR. SCOTT-JONES: I'm sorry. I just missed the first part of what you said. I just wanted to know how to reference this: is it from your company, this diagram?
DR. WEST: Yes. Advanced Cell Technology prepared that diagram.
DR. SCOTT-JONES: Okay.
DR. SHAPIRO: Okay. We're going to have to bring this part of our discussion to a close here with Carol.
DR. SCOTT-JONES: Actually, David is the one who wanted to ask a question.
DR. COX: Two very quick questions. The first deals with this diagram, too.
DR. WEST: Uh-huh.
DR. COX: Is it in fact the case that you demonstrated that, by the ACT technique, that stuff is a fully compatible transplant?
DR. WEST: No, that's purely based on biological theory. The concept is -- I'm sorry?
DR. COX: It's theoretical, as the question mark is there, and the other approaches are theoretical but they are incompatible transplants, right?
DR. WEST: Yes. It's based entirely on the belief that not only major histocompatibility anlagens but many other minor histocompatibility anlagens pose certain problems associated with allogeneic graphs.
DR. COX: My second question is a more complicated one and in some ways unfair, so I don't mean it to be sort of an "in your face" question. But there are a lot of people who feel very strongly about embryo research in this country, and it provides them zero solace that you're not going to take these blastocysts and use them to try to create an organism. And so what would you say to those people?
DR. WEST: Well, what I would refer to is to the mention of fire. Fire, as you know, is a powerful source for good or bad. And I'm sure in the early days those who invented fire noted that it could be used to cook food and prevent food poisoning, and to heat their homes, and save lives. On the other hand, it can burn your house down. Our intent here is to find all of the good applications of these technologies, accelerate them as much as we can for the treatment of human disease and to alleviate human suffering, and at the same time make the world the type of place that we want to live in.
DR. COX: Do you have any recommendations about how we might prevent the bad from happening while allowing the good to go forward?
DR. WEST: Well, I think, as in the United Kingdom, a decision to potentially criminalize or make other prohibitions against the cloning of a human being may be a good first step.
DR. COX: Thank you.
DR. SHAPIRO: Thank you very much. Tom, you had a question?
DR. MURRAY: Well, actually, David asked pretty much the question I wanted to ask him. I thought your answer was not -- I'm sorry -- was not very good at all. I listened carefully to the answer, and I just thought it was a terrible analogy.
DR. WEST: Remind me of the question then.
DR. MURRAY: Well, the question. There are people out there in the United States who are morally offended at the thought of any research on an embryo, and probably even moreso -- well, certainly even moreso at the notion that one would create a human embryo for the purpose of doing research on it. We just have to acknowledge that that's a fact about the United States. That is why Congress told NIH it may not fund any research on human embryos, and that has had some -- that prohibition on funding has had, in the opinion of some of us, some fairly deleterious impacts on the quality and the ethical review of some research. I have to be honest about that. You responded with the analogy of fire. That's just not going to comfort any of those folks. It's not even really going to respond to their concerns. Their concerns are that embryos are, to them, the same as a person. And is there any answer we could give? I take it what I'm hearing is that the constructs that you're creating by using the bovine oocyte in the human nucleus might in fact be meant to avoid this problem.
DR. WEST: Well, I think the nuclear transfer technologies have demonstrated that potentially every cell in the human body has the genetic potential of becoming a human being. And so....
DR. MURRAY: They're not all sitting inside oocytes.
DR. WEST: Yes, that's correct.
DR. MURRAY: It's a big difference.
DR. WEST: That's correct. And I think that the -- that all of these technologies together, I think, have brought us to the point where we as a nation need to think long and hard about what is our stance toward the fertilized human zygote, the morula and the blastocyst. And I think there are many points of reference here. And I think all of them need to be carefully considered hand in hand with the medical benefits gained from using these technologies. I don't mean to be evasive. I'm thinking I'm probably telling the Commission things that the Commission already knows. I think the word "embryo" carries with it a lot of connotation, a lot of emotion. I think much of that emotion is well-placed. I think human life is a sacred thing. I think a developing embryo and fetus should have a status more than just a conglomeration of cells. But when we get back to the point of a somatic cell, if we took this to the point where we believed that every human somatic cell was a human being, had the potential to be a human being....
DR. MURRAY: That's an argument.
DR. WEST: But that's a....
DR. MURRAY: I agree. I appreciate it. I think most of your answer has been responsive, but I really would like to know, in your opinion, whether the constructed, created bovine, the nuclear oocyte in the nucleus, is potentially a viable human embryo.
DR. WEST: I would be glad to give you my personal opinion. It's just that, but my personal opinion is that up to the stage of gastrulation, the embryo, if cleaved in two, leads to identical twins and therefore at that stage of development there is no individualization. Otherwise, you would have somehow cleaved the being into two people. And after gastrulation there is sort of a line drawn in the embryo. There is a point at which differentiation is begun. At that point, if you divided the embryo you would get a phenomenon like Siamese twins, or other developmental abnormalities. And there was a sort of general rule in in vitro fertilization that embryos up to gastrulation have a distinct status from embryos after gastrulation. All of these technologies would involve the development of small aggregations of cells, the blastocysts prior to gastrulation. And if you ask my personal opinion, I would suggest that we should draw a line in the sand where the embryo draws a line at the primitive streak stage, and suggest that nuclear transfer to make primitive cells up to -- or embryos up to the point of gastrulation should be considered under certain carefully circumscribed uses for medical benefit.
DR. MURRAY: You've actually conflated two things, identity and viability, and I understand the argument. I'm familiar with those arguments, but I take it, at least by inference, that you think such constructs that you created might in fact be viable whether or not they split. If they split they might be two viable embryos, but it might be viable. Am I advising correctly?
DR. WEST: I'm sorry. Could you clarify that question?
DR. MURRAY: I think that's -- I think we're -- that's all right.
DR. WEST: Okay.
DR. SHAPIRO: Okay. I want to thank you very much for being here and for being so candid and responsive to us, to the questions of the Commission. I very much appreciate it. We're going to take approximately a 20-minute break now, and then we will do public comments after the break. So please, at 3:30 I'd like all commissioners back, since I do want you to be here for the public comments.