Progress in understanding - and then controlling - the mechanisms of cellular differentiation has been rapid in the past year or two. The more that is learned, the closer we come to advanced regenerative medicine, capable of repairing or replacing any diseased tissue to order. Along the way, just as for cancer research, all that is learned about our cells can be taken and applied to meaningful anti-aging science. Today, I ran across a couple of examples of the sort of work presently taking place:
The lining of the respiratory and gastrointestinal tracts, the pancreas, the liver, the thymus and the thyroid all have their origin in a structure of the early embryo called the anterior endoderm. Josh Brickman and his team have shown that, in the African clawed frog, the anterior endoderm forms through a cascade of activities of different molecules, leading, ultimately, to the increased activity of a protein called Wnt.
They then used mouse embryonic stem cells to demonstrate that the same cascade exists in mammals and to suggest that this activity of Wnt might be exploited to contribute to current efforts to direct embryonic stem cells to become pure anterior endoderm cells. This would be the first step in obtaining, for example, liver cells and insulin-producing beta cells of the pancreas, in the laboratory.
This next article is particularly exciting; modern tools are enabling deep and detailed insight into the way in which our cells actually work.
There is a lot of excitement in stem cell biology these days about the possibility of rationally and efficiently generating particular cell types from different stem cells for therapeutic purposes. As we better understand the underlying genetic circuitry that orchestrates development of a particular kind of stem cell into a specialized cell type, we should be able to manipulate it for such purposes.
A major scientific puzzle, said Singh, has been how and why immature hematopoietic stem cells initially express genes that are characteristic of more than one cell lineage. "One can imagine that the cells are molecularly previewing their developmental options by turning on at low levels cell-type-specific genes, and thereby revealing the developmental potential that they have," said Singh.
Understanding the circuitry that controls this critical "transcriptional priming" is central to understanding how different kinds of stem cells develop and what kind of developmental potential they have
Read the whole thing - it really is very promising. Biochemistry is always more complex than you think at first, but the veils are falling away ever more rapidly. Twenty years from now, a range of very impressive regenerative medical technology will result from these first steps.