Differences between bone marrow and lung endothelial cells.

To elucidate the mechanisms by which hematopoietic progenitor cells selectively lodge in bone marrow, we established endothelial cell lines derived from bone marrow and lung and then examined the transendothelial migration of hematopoietic progenitor cells by using cells was examined by a Transwell migration assay. Hematopoietic progenitor cells transmigrated through bone marrow endothelial cells but not through lung endothelial cells. Transendothelial migration of hematopoietic progenitor cells was inhibited by anti-vascular cell adhesion molecule (VCAM)-1 antibody. These findings suggest that transendothelial migration of hematopoietic progenitor cells is specific for bone marrow endothelial cells and that this difference may play an important role in the selective homing of hematopoietic progenitor cells to bone marrow.