Ocata Therapeutics Inc fka OCAT

[rocky822]

Single-Cell Storm

Susan Okie, M.D.

Perspective
by Okie, S.

Scientists at Advanced Cell Technology, a California company, reported in August that a single cell taken from an eight-cell human embryo can sometimes be coaxed to produce embryonic stem cells, suggesting that such "biopsies" might be a way to generate new stem-cell lines while preserving embryos.

The report, published online by the journal Nature,1 stirred up considerable controversy, in part because both the journal's initial press release and a podcast interview with senior author Robert Lanza gave the impression that two new lines had been created without destroying any embryos. "What we have done, for the first time, is to actually create human embryonic stem cells without destroying the embryo itself," Lanza said in the podcast.2 On the contrary, all 16 donated embryos used in the study were destroyed during the experiments, a fact that was stated, although not emphasized, in the article. A total of 91 cells (called blastomeres) were individually removed from the early-stage embryos and were cultured, in most cases in dishes with other blastomeres. Two of the blastomeres gave rise to embryonic stem-cell lines. The results — together with unpublished work by the authors — suggest, in principle, that single-cell biopsies (which are done on some embryos in IVF clinics for preimplantation genetic diagnosis) could be used to derive stem cells without destroying embryos.

Nature issued clarifications of its press release shortly after its online publication and again 2 days later, citing "internal communications problems." Meanwhile, the findings were prominently reported in the national media as a possible solution to the Bush administration's opposition to the use of federal funds for research on new stem-cell lines. A White House spokeswoman was quoted in news reports, however, as saying that the new technique would not resolve the President's ethical concerns about the use of embryos in research. Later the same week, Richard Doerflinger of the U.S. Conference of Catholic Bishops, a prominent critic of such research, e-mailed reporters, charging that the study had been misrepresented. "This experiment left no embryos alive and solves no ethical problems," Doerflinger wrote.

At a hearing of the Senate Appropriations Subcommittee on Labor, Health and Human Services, Education, and Related Agencies in early September, Lanza received a tongue-lashing from Senator Arlen Specter (R-PA), a strong supporter of stem-cell research. "It's a big black eye if scientists are making false and inaccurate representations," Specter told Lanza.

Lanza maintained that he had been quoted out of context by interviewers and said he had been shocked by the critical response. "Our paper was 100% correct," he said. "It's very clear that there's a lot of politics going on here."

Advanced Cell Technology has had financial troubles, but its stock price experienced a bump after the Nature publication, and company officials are clearly hoping that cell lines made with the use of the technique will become eligible for federal research funding. However, James Battey, Jr., chairman of the NIH Stem Cell Task Force, said he doubted that the new method will silence the concerns of some critics. For example, he said it is not certain that removing a cell from an eight-cell embryo does no harm, even though hundreds of apparently healthy infants have been born from embryos that underwent the procedure for genetic testing. It is also unknown whether a single human blastomere can develop into an embryo, as is possible in animals. "My guess is, absent complete reassurance on these issues, there will be individuals who will find this protocol morally and ethically problematic," Battey predicted.

http://content.nejm.org/cgi/content/full/355/16/1634