title: Haemopoietic growth factors stimulating murine megakaryocytopoiesis: interleukin-3 is immunologically distinct from megakaryocyte-potentiator.
abstract: The biological and immunological properties of stimulators of in vitro murine megakaryocytopoiesis were studied using a heterologous anti-interleukin 3 (IL-3) serum. All megakaryocyte colony development was inhibited with the antiserum using three sources of IL-3, including WEHI-3 cell conditioned medium (WEHI-3CM), pokeweed mitogen-spleen conditioned medium (PWM-SCM) and recombinant IL-3. The data indicate that IL-3 is an absolute requirement for murine megakaryocyte colony development in this system. By comparison the antiserum abolished all myeloid colony growth stimulated by WEHI-3CM, but not PWM-SCM. The in vitro development of single megakaryocytes stimulated by a second putative growth factor, megakaryocyte-potentiator, was not inhibited by the antibody. The antiserum precipitated a 26 kd molecular weight protein from a radioiodinated sample of IL-3. No crossreactivity by the antiserum with other colony-stimulating factors (CSF) including CSF-1 and granulocyte-macrophage CSF was observed. The data indicates that IL-3 and megakaryocyte-potentiator are immunologically unrelated and provides further support that the two factors are separate molecules.
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D000918:Antibody Specificity; D001854:Bone Marrow Cells; D006133:Growth Substances / Q000276:immunology* / Q000494:pharmacology; D006410:Hematopoiesis / Q000187:drug effects*; D006412:Hematopoietic Stem Cells / Q000166:cytology / Q000187:drug effects; D007377:Interleukin-3 / Q000276:immunology* / Q000494:pharmacology; D008533:Megakaryocytes / Q000502:physiology*; D051379:Mice; D008970:Molecular Weight
chemical_list: D006133:Growth Substances; D007377:Interleukin-3; D000110:Acetylcholinesterase