Last Wednesday some significant development happened in the stem cell research front which was moving at snail’s pace in the last five years. The US and Japan researchers announced thrilling development in the exploration, claiming their ability to make adult cells generate embryonic stem cells. This announcement is a bold advancement as the US congress gets ready to vote on legislation for the expansion of federal funding for the field to include studies on excess IVF embryos.

In multi-cellular organism, stem cells are primal cells which can renew themselves through mitotic cell division. These cells can generate wide variety of specialized cells for all tissue types. For mammalian stem cells, three broad categories are available; namely embryonic stem cells derived from blastocysts, adult stem cells, which generally available in adult tissues and cord blood stem cells, found in the umbilical cord. In an embryo, all kinds of cells are derived from stem cells while for adult these act as repair system for the body, making up for the damaged cells.

The announcement published in the journals Nature and Cell Stem Cell, is really a big stride in the advancement of cell stem research and can be considered as a true milestone. Three research groups worked independently, to get to the same outcome. The first group worked in Kyoto University led by Shinya Yamanaka, successfully coaxed a mouse skin cell to reverse its development and to get back to embryonic stage at which it produced stem cells. One of the other two groups, who are based at Harvard Stem Cell Institute (HSCI) proved that stem cells can be generated even from fertilized mouse zygotes. The third group of Whitehead Institute for Biomedical Research at MIT reached the same conclusion working separately. This invention hit hard the earlier belief that stem cells cannot be produced from fertilized embryos embarked on the development path.

Though the experiment is yet to be carried on human stem cells, but considering the fundamental similarities between stem cell generation principle in mice and human, scientists are hopeful of getting similar success in human cells. If the success can be made on human cells too, then it will indeed be possible to take a skin cell from an adult and regenerate it into embryonic cell. In other words, a person can heal himself, at least in theory. Yamanaka, last year came up with similar announcement but stem cells he generated were unstable. But this time, they progressed in their approach along with the other two groups and concluded that the process indeed works. Their methods proved that stable stem cells can go back to egg and sperm which can produce healthy mice.

Among all the elations there are concerns too. Scientists in order to turn back the aging of stem cells used a retrovirus vector which for human being is not easy to control and can cause infectious disease like HIV. So before testing the method on human they need to find other modes of transport for the critical compounds. The major apprehension is scary, as two of the four factors that can turn back the clock on adult cells so efficiently are carcinogenic. ‘Figuring out how to reprogram cells without directly exposing the cell to the cancer-causing effects of these genes is a major area of scientific activity, and would have to occur before we could consider using similar factor in humans,’ says Eggan.of HSCI. Eggan’s group has derived an alternative approach for generating tailored stem cells using Nucleus Transfer method - Taking nucleus from a skin cell and transplanting it into an egg cell which has its nucleus removed. This method is not yet fully successful as it has its own difficulties.

With all the pros and cons, success and failures, controversies and opinions about stem cell research, the scientists are working relentlessly towards its advancement. Biologists all around the world believe that stem cells will one day stop the aging process. This declaration of the new invention is indeed a great success towards that step and we now can count days for some more exciting claims on stem cell research.

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