Hitting Rewind
Date: March 13, 2007
Time: 10:05pm est

"In the end, research that avoids ethical controversies will prevail." So says Prof. Kim Kye-seong , a stem cell researcher from South Korea who avidly pursues alternatives to embryo-destructive research . He is one of many scientists who understand that the real way forward in ESC research is through alternatives that avoid damaging or destroying human embryos. Prof. Kim and his Korean colleagues have joined a growing throng of scientists across the globe who are placing their bets on one option in particular that has generated feverish interest: direct cell reprogramming.

Reprogramming-if it can be done (and the scientists I know are pretty sure it can )-would be like taking any cell in the human body and " hitting rewind ," essentially sending that cell's nucleus back to a state which would render the cell "pluripotent", capable of producing any tissue type in the human body, equivalent in versatility to human embryonic stem cells. Furthermore, these stem cells would be genetically matched to the person who donated the body cells. They could then be used to grow tissues for future use in tissue replacement therapies (everything from regeneration of damaged heart tissue to Parkinson's to spinal chord injury). A perfect genetic match, these tissues would not be rejected by the donor's immune system. Most importantly, there would be no embryo created, destroyed, damaged or used in any way at any point in the process.

Direct cell reprogramming offers the possibility of turning a normal adult body cell into a cell with the properties of an embryonic stem cell, but without involving human embryos in the process.

In August 2006, the journal Cell published research by a Japanese team of researchers lead by Shinya Yamanaka. In that research, Yamanaka reported successes in reprogramming mouse cells. By altering just four genetic factors the team was able to change adult mouse cells into pluripotent mouse stem cells. This important breakthrough has been a crucial catalyst in determinging whether human adult cells can be similarly reprogrammed using this method.

As stated in a white paper published in January by the White House Domestic Policy Council:

In November 2006, scientists from the School of Biosciences and Institute of Genetics, University of Nottingham, Loughborough, reviewed the recent scientific advancements in reprogramming and concluded there is sufficient evidence demonstrating that adult cells can be reprogrammed and that cell-based approaches for therapeutics may be a realistic expectation in the future. The study reviewed nine reprogramming approaches that are commonly used today and commented on their respective advantages and limitations. While it is too early to tell which approaches may or may not work, the sheer number of methods makes clear that there may be several different ways to induce reprogramming of adult cells in the future.

This is all good news, and there is more to be expected!

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