Researchers report development of embryonic stem cells without destroying embryo

A Massachusetts company, working with University of Wisconsin-Madison researchers and others, says it has discovered a way to generate embryonic stem cell lines without interfering with the developmental potential of the embryos.

The company, Advanced Cell Technology, Inc. of Worcester, Mass., says the research came up with a method of deriving stem cells in mice using a technique of single-cell embryo biopsy similar to that used in preimplantation genetic diagnosis (PGD) to test for genetic defects.

The research is described in an article in Nature magazine, which is reporting the article in advance on its website.

"The most basic objection to embryonic stem cell research is the fact that embryos are deprived of any further potential to develop into a complete human being," said Robert Lanza, medical director at Advanced Cell Technology, and senior author of the study. "We have shown in a mouse model that you can generate embryonic stem cells using a method that does not interfere with the developmental potential of the embryo. It is important to note that this work was performed in the mouse and needs to be extended to the human species. It would be tragic not to pursue all options and methods available to us to get this technology to the bedside as soon as possible," added Lanza.

Five embryonic stem (ES) cells and seven extraembryonic (trophoblast) stem cell lines were produced from single mouse blastomeres, which maintained normal karyotype (chromosome type) and markers of pluripotency or TS cells for up to more than 50 passages. The ES cells differentiated into derivatives of all three germ layers both in vitro and in chimeric offspring and teratomas, according to Advanced Cell Technology. Single-blastomere-biopsied embryos developed to term without a reduction in their developmental capacity.

"In the past, stem cell lines have been isolated from the inner cell mass of blastocysts and, in a few instances, from earlier, cleavage-stage embryos," said Young Chung, senior scientist at Advanced Cell Technology, and first author of the paper. "We generated five ES and seven trophoblast stem cell lines from single mouse embryo cells. The stem cells were able to generate all the cell types of body, including nerve cells, bone, and beating heart."

"Ultimately the goal of stem cell research is to provide new treatments for what are now incurable diseases," added Michael West, president and chief scientific officer at Advanced Cell Technology.

Julie John and Lorraine Meisner of UW-Madison are among the research paper's authors.

¥ The paper can be viewed in its entirety at www.advancedcell.com under the "Scientific Papers" heading.