Hematopoietic Stem Cell and Its Growth Factor

Rhesus monkey is a good experimental system for man in bone marrow transplantation. Attempts were made to adopt the human progenitor culture system to the rhesus bone marrow. Conditioned medium from phytoagglutinin stimulated human lymphocytes was suitable for the growth of rhesus progenitors in the standard methylcellulose culture assay. The major modification was the need to read BFU-E and CFU-GEMM at day 12 due to the degeneration of cells in the colonies. Monoclonal antibodies against human nonlymphoid leukemia cell lines which have reactivities against human progenitors did not show significant cross-reactivities against the rhesus marrow. Monoclonal antibodies to rhesus bone marrow cells were made. Although no antibodies specific for the stem cells were obtained, an antibody reactive with lymphoid as well as more mature myeloid cells was useful to enrich for progenitor cells. The bone marrow cells depleted of reactive cells to the monoclonal antibody was functional in vivo in that they reconstituted the bone marrow of irradiated autologous and allogeneic recipients. Monoclonal antibodies against rhesus T cells and B cells were also established. These anti-bone marrow and anti-lymphocyte antibodies may be useful for further studies of the rhesus model system. Keywords: Hybridoma, Hemopoietic cells, Hemopoiesis.