CD43 expression by murine lymphohemopoietic progenitors.

CD43 is expressed by many types of mature blood cells including T-lymphocytes, activated B-lymphocytes, neutrophils, monocytes, and platelets but not non-hemopoietic cells. Defective CD43 is seen in patients with Wiscott-Aldrich syndrome. We have investigated CD43 expression by hemopoietic progenitors of normal and 5-fluorouracil(5-FU)-treated mice. Bone marrow cells were enriched for progenitors by a combination of density centrifugation and negative immunomagnetic selection using lineage-specific monoclonal antibodies. They were then separated based on expression of Ly-6A/E and CD43. Approximately 50% of the Ly-6A/E+ cells of both normal and 5-FU-treated mice were CD43neg-low, while the rest of the cells were CD43bright. The majority of the colony-forming cells including lymphohemopoietic progenitors that gave rise to both myeloid and B-lymphoid lineages were present in the Ly-6A/E+CD43bright cell population. Therefore, Ly-6A/E+CD43bright cells were approximately 2-times enriched for the progenitors relative to Ly-6A/E+ cells. Anti-CD43 antibody is useful in isolation of primitive murine hemopoietic progenitors.