title: Studies of human megakaryocytopoiesis using an anti-megakaryocyte colony-stimulating factor antiserum.
abstract: We produced an antiserum by immunizing rabbits with purified human megakaryocyte colony stimulating factor (Meg-CSF). With the use of an anti-Meg-CSF IgG fraction (AM-IgG), we detected immunoreactive Meg-CSF both in human aplastic anemia serum (AAS) and normal serum. Based on our immunological and biological analyses, Meg-CSF appeared to be antigenically as well as functionally distinct from human urinary erythropoietin (EPO) and thrombopoietic stimulating factor. The AM-IgG fraction was able to suppress the ability of both aplastic anemia serum and purified Meg-CSF to promote megakaryocyte colony formation. In addition, the supernatant formed after immune precipitation of the AAS with AM-IgG no longer possessed Meg-CSF-like activity. The AM-IgG did not suppress the ability of EPO, phytohemagglutinin-stimulated leukocyte conditioned medium (PHA-LCM), or PHA-LCM + EPO to promote erythroid, granulocyte-macrophage, or mixed colony formation, respectively. The use of this antibody has further defined the dependency of human megakaryocytopoiesis on Meg-CSF.
mesh_terms: D000741:Anemia, Aplastic / Q000097:blood; D003114:Colony-Forming Units Assay; D003115:Colony-Stimulating Factors / Q000276:immunology*; D004591:Electrophoresis, Polyacrylamide Gel; D004921:Erythropoietin / Q000652:urine; D006410:Hematopoiesis; D006801:Humans; D007106:Immune Sera; D005779:Immunodiffusion; D007122:Immunoelectrophoresis; D007074:Immunoglobulin G; D008533:Megakaryocytes / Q000166:cytology*; D010835:Phytohemagglutinins / Q000494:pharmacology
chemical_list: D003115:Colony-Stimulating Factors; D007106:Immune Sera; D007074:Immunoglobulin G; D010835:Phytohemagglutinins; D004921:Erythropoietin