Expression of antigens on haemopoietic progenitor cells in bovine bone marrow.

We analysed the surface phenotype of bovine bone marrow erythroid and myeloid progenitor cells with monoclonal antibodies (mAbs) from the Second Workshop. For the antibodies tested, no difference could be observed in burst-forming unit (erythroid) and colony-forming unit (erythroid) both are positive for BoCD44, BoWC9, MHC Class I, transferrin receptor and the p150/158 antigen detected by BT3/8.12, but neither express BoCD11a, BoCD45, BoWC5 or the antigen recognized by mAb Bo116. The myeloid progenitor cells, colony-forming unit (granulocyte/macrophage), can be discriminated from the erythroid progenitors by the absence of a transferrin receptor and the expression of BoCD11a and BoWC5 antigens. By selecting the right panel of mAbs, it should now be possible to enrich bone marrow cells for erythroid and/or myeloid progenitor cells.