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Hi All, Stem Cells (BioTech) have suddenly caught the fancy of investment letters.... I like this "take" on stem cells..... murray MSN MoneyCentral Investor - Insight Strategic News Service - SNS Tech Trends - 6/4/2001 Mark Anderson is president of Technology Alliance Partners, and of the Strategic News Service. Reassessing cell determinism There are moments in the history of each science that offer the real excitement of revolutions in our understanding, and one of those moments, at least for me, came a couple of weeks ago. Having studied biology for most of my adult life, I am familiar with the now-old paradigm about how cells get to be what they are. It went something like this: cells increase in their specificity as the fertilized egg goes through increasing divisions, and this process results, finally, in an embryo, and then a newborn, with most (if not all) cells achieving their type: skin, brain, digestive organ, muscle, bone, etc. Once this has happened, these cells can continue to divide (as, say, muscle cells), but re-differentiation into other cell types is considered essentially a sport case, rare if ever seen. In other words, the body makes its cells, they go into growth and/or self- replacement mode until their repair mechanisms slow and falter, and then you die. The developmental biology community has been alive with excitement over stem cells for many years now, and everyone is familiar with some of the major steps in this story: discovering that bone marrow cells could regenerate blood cells of leukemia victims (smart kids will want to argue about my categorization of this one), the apparent ability of embryonic stem cells to develop into a variety of tissues, the discovery of stem cells in human adipose fat tissue, and now … Three weeks ago, Yale Cancer Center researcher Diane Krause published a paper in the journal Cell, together with Neil Theise, of New York University School of Medicine (both are M.D.s), and with other collaborators from their own schools, and the Johns Hopkins School of Medicine. Here is what they found, using mice: If you irradiate a female mouse (killing stem cells), and then transplant a single male-derived (therefore Y-chromosome-marked) adult stem cell from bone marrow, a surprising thing happens: the male stem cells differentiate into not only bone marrow and blood cells, but also -- lung, esophagus, stomach, small and large intestine, liver and skin cells. Wow. Lest you think that this has no connection to humans, prior experiments of the same kind, but more limited scope (looking only at new liver cell generation from stem cells), were reproducible in humans. Summary: There appears to be a completely new ecology of cell types at work in our bodies, whereby we give ourselves our own bone marrow transplants for the replenishment of other tissues on some kind of as- needed basis. There are many uncrossed Ts here, but the basic idea is wonderful, and totally new. Now you're excited.. ©2001 Strategic News Service LLC; free trial subscriptions to Strategic News Service are available at http://www.tapsns.com. Mark Anderson is a principal in the investment advisory firm Resonance Capital Management LLC. Under no circumstances does the above information represent a recommendation to buy or sell stocks. http://moneycentral.msn.com/articles/invest/trends/6997.asp?0si=- ******** ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn