PEOPLE AND T-CELLS HAVE TO MAKE A COMMITMENT AT SOME POINT

From Science Daily:  " When does a cell decide its particular identity? According to biologists at the California Institute of Technology (Caltech), in the case of T cells -- immune system cells that help destroy invading pathogens -- the answer is when the cells begin expressing a particular gene called Bcl11b.

The activation of Bcl11b is a "clean, nearly perfect indicator of when cells have decided to go on the T-cell pathway," says Ellen Rothenberg, the Albert Billings Ruddock Professor of Biology at Caltech and senior author of a paper about the discovery that appears in the July 2 issue of the journal Science. The paper, coauthored by Caltech postdoctoral scholar Long Li, is one of three in the issue to examine this powerful gene.?"

When electron micrography came into being and be used, it opened horizons for exploration that were not even dreamed about prior.  Researchers can now see so much that was previously unattainable to them.  One would assume, if one didn't know better, that there were no more frontiers to breakthrough.  Not so, that was followed by CATScan, MRI, PetScan and so many new breakthroughs coming so quickly that we are constantly building the medical and diagnostic arsenals.

""Stem cells and their multipotent descendents follow one set of growth rules, and T cells another," says Ellen Rothenberg, the Albert Billings Ruddock Professor of Biology at Caltech and senior author of a paper about the discovery, "so if T-cell precursors don't give up certain stem-cell functions, bad things happen." Like stem cells, T cells have a remarkable ability to grow -- but as part of their T-cell-ness, she says, they do so "under incredibly strict regulation. Their growth is restricted unless certain conditions are met." The cells need to shift their growth-control rules during development; after development, because they still need to grow, the cells and their daughters need an active mechanism to make the change irreversible. Bcl11b is a long-sought part of that mechanism."  To read the whole article, click here.