Thursday, September 14, 2006

Text From Lanza's U.S. Senate Appearance

Last week, Robert Lanza of Advanced Cell Technology of Alameda, Ca., appeared before a subcommittee of the U.S. Senate. Two U.S. senators excoriated him in connection with ACT's announcement of a new method of extracting ESC. Here is the complete text of what Lanza prepared for the Senate Labor, Health & Human Services, and Education Appropriations Subcommittee. The text was supplied by ACT at the request of the California Stem Cell Report.

(September 6, 2006) Good morning, Mr. Chairman and distinguished members of the committee. My name is Robert Lanza and I am Vice-President of Research & Scientific Development at Advanced Cell Technology, a biotechnology company in the field of regenerative medicine. I am also an Adjunct Professor at the Institute of Regenerative Medicine at Wake Forest University School of Medicine.

I would like to thank you for the opportunity to testify today on our technique for obtaining human embryonic stem (hES) cells from single blastomeres. As you know, hES cell lines are conventionally isolated from leftover embryos created for couples seeking in vitro fertilization (IVF). I join with the sponsors of Senate Bill HR 810 in my belief that scientists funded by the NIH should have access to stem cells derived from the hundreds of thousands of such surplus embryos that will otherwise be discarded. I know that you share my frustration that this important legislation was vetoed by the President.

Therefore, at the outset, I would like to make it absolutely clear that the single-cell derivation technique we’ve developed is not a replacement for existing methods of generating embryonic stem cell lines. In fact, our intention is quite to the contrary. We think it would be tragic not to pursue all the options and methods currently available to us to get this technology to the bedside as soon as possible. That being said, our hope is that the new method we describe in Nature can be used to increase the number of stem cell lines that qualify for Federal funding within the framework of existing US laws and regulations – and thus give the field a very much needed jump-start.

Current US law prohibits the use of federal funds for research in which human embryos are harmed or destroyed. As a result of this policy, the field of stem cell research has been crippled by the lack of quality stem cell lines. At present, there are only a handful of NIH-approved lines, all of which are potentially contaminated with animal pathogens that could lead to serious health risks; whereas others are difficult to grow and have started to display genetic abnormalities. Nor do they reflect the genetic diversity of the population, both in terms of their clinical potential and their value to those of us trying to understand the cause of various human diseases.

The approach we have developed does not involve the destruction of embryos, nor do the biopsied cells ever develop into an embryo at any point. The procedure is commonly known as PGD (preimplantatation genetic diagnosis) and is a well-established technique that has been used for a decade by IVF clinicians to generate thousands of healthy babies worldwide. In PGD, a single cell – known as a blastomere – is removed from an 8-cell-stage embryo for genetic testing. By growing the cell overnight, the resulting cells could be used for both PGD and the generation of stem-cells without affecting the clinical outcome of the procedure or the subsequent chances of the couple having a child. Numerous reports show that the survival rate is unaffected by the biopsy procedure, and that the subsequent development and chances of implantation are the same for both normal and biopsied embryos In our study, multiple individual cells where removed from embryos in the same way as would be employed in the clinical setting with PGD. Although those particular embryos were not allowed to develop further, we also carried out studies which confirmed that the biopsy procedure we used could be used without destroying the embryo. I want to be entirely clear on this point. The embryos used to create stem cell lines in our study were destroyed; however, in control experiments, single-cell biopsied embryos were allowed to continue development, and they did indeed develop to a more advanced (blastocyst) stage – they were all frozen and remain alive.

In fact, they continued development at the same rate as nonbiopsied embryos. We also showed that individual biopsied cells had the capacity to generate stem cells. Nineteen ES-cell like outgrowths and two stable embryonic stem cell lines were derived from 91 blastomeres. These stem cell lines have been growing for more than 8 months, and are genetically normal and able to generate cells from all the germ layers of body, including nerve cells, blood cells, and even retinal cells that could be used to prevent blindness.

Of course, hES cells derived this way could be of great potential benefit, not only for the medical research community, but also for the children and siblings born from transferred PGD embryos as well. The cells would be genetically identical to the child, and could be frozen down and used throughout the lifetime of the person – for instance, if they develop diabetes or heart disease.

I would now like to address several objections to the use of this procedure. First is that the technique may not be entirely without risk to the embryo, however minimal. We agree, and until remaining doubts about safety are resolved, we do not recommend the procedure be applied to healthy embryos outside the context of PGD. However, in PGD a cell is already removed and could be used to create stem cells without any added risk to the embryo. Second, concerns have been raised as to whether individual cells, such as those used in our study, are totipotent and could potentially generate a human being. It is our opinion that this is not the case.

Recent reports show that cell fate is already being determined at the 2 to 4 cell stage. Importantly, individual cells from an 8-cell-stage embryo, such as those used in our study, have never been shown to have the intrinsic capacity to generate a complete organism in any mammalian species – not even in a mouse or rat. And finally, questions have been raised whether the technique is completely applicable in the clinical setting. We believe it is and are working on procedures that can be utilized by clinicians in the IVF clinic environment. And thus, we believe it is now possible to create new stem cell lines without destroying human embryos. With the support of Federal funding, the single-cell derivation technique could provide new robust (and animal-product-free) stem cell lines for medical research and human clinical trials.

Since I testified here a year ago, we’ve managed to move the singlecell derivation technique from the mouse to the human. But in the meantime another million people have died of diseases that could potentially be treated – and possibly cured—using future stem cell therapies. How long are we going to allow this intolerable situation to continue? Stem cell scientists sorely need more lines that qualify for Federal funding. Make no mistake about it, there are many promising alternatives out there, but the conventional and singlecell derivation techniques are a reality – here and now. There are those who would want to set this research back, but there is a very real human tragedy out there, and it would be a shame not to use this opportunity to try to lessen the misery of so many Americans with disorders and disabilities. This is my hope, and it could start here with this Committee. Now is the time to move, while the United States is still in the forefront of this research, and while there is still time enough to develop therapies that could be used to help alleviate the suffering of those we know and love.

Thank you for the opportunity to address your Committee. I hope you find these comments helpful to your work.
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