The Nature study augments earlier work by Dr. Morrison and his team that showed endothelial cells and perivascular cells lining the blood vessels in the bone marrow create the environment that maintains haematopoietic stem cells, which produce billions of new blood cells every day. The latest study shows that bone-forming cells create the environment that maintains early lymphoid progenitors.
"Our research documents that there are different niches, or microenvironments, for blood-forming stem cells and restricted progenitors in the bone marrow," Dr. Morrison said. "One way that bone marrow makes different kinds of blood-forming cells is by compartmentalizing them into different neighborhoods within the marrow."
The researchers identified niches for stem cells and early lymphoid progenitors by determining which cells are the sources of a growth factor (CXCL12) necessary for the proliferation of those two populations of blood-forming cells. By taking the same approach for other growth factors in the bone marrow, researchers should be able to map the niches for every kind of blood-forming progenitor cell in the bone marrow, Dr. Morrison said.
The UTSW paper's first author is Dr. Lei Ding, a former postdoctoral research fellow at the Children's Research Institute and the Howard Hughes Medical Institute (HHMI) at UT Southwestern. Dr. Ding is now an assistant professor at Columbia University.
|Contact: Jeff Carlton|
UT Southwestern Medical Center