Research on embryonic stem cell cloning advances

October 06, 2011|By Carolyn Y. Johnson, Globe Staff

Similar research had been pursued five years ago by scientists at Harvard,…

A team of New York scientists has taken a major step toward the goal of creating cloned human embryonic stem cells for therapeutic uses - but many technical hurdles remain before the cells could be used in patients.

The feat also highlights legal, ethical, and financial hurdles that stymied similar research being pursued by Harvard scientists. The New York group was led by a scientist who was trained at Harvard.

In the new work, scientists at the New York Stem Cell Foundation’s independent nonprofit laboratory used 270 human eggs from 16 women to create 13 early-stage embryos and two stem cell lines - batches of cells with the capacity to form all the cells in the body. One cell line carried the genome of a patient with type 1 diabetes, the other the genes of a healthy adult. But there was a major caveat: The two stem cell lines also carried the original genetic material of the egg donor. Researchers reported in the journal Nature yesterday that the development of the egg came to a halt if they tried to remove the original genome.

Cells with the extra genetic material could not be used to treat patients, but scientists not involved in the research said it could yield important clues about how to more efficiently and completely reprogram an adult cell into an embryonic stem cell. Scientists envision such cells could be useful for creating patient-specific cells that could one day be used to generate or repair tissue in patients with diseases such as diabetes and Parkinson’s. The research also shows how funding by private donors and a unique set of protocols allowed such difficult work to proceed in the first place.

“It’s really a testimony to the kind of opportunity they had; it brought together this unusual institutional approval, but also the financing,’’ said Dr. George Q. Daley, a stem cell scientist at Children’s Hospital Boston.

Daley led one of two teams of researchers at the Harvard Stem Cell Institute that five years ago received approval from the university to attempt a similar project. But because of restrictions, including a state law prohibiting compensation to egg donors beyond expense reimbursement, those efforts moved slowly, recruiting only one woman as an egg donor and using low-quality eggs from a fertility clinic.

“We stopped in large part because we felt we were hitting our heads against the wall; because the eggs were poor quality, and it was just an expensive process at a time when NIH funding was getting tougher,’’ Daley said.