TISSUE SOURCES OF MURINE MEGAKARYOCYTE POTENTIATOR - BIOCHEMICAL AND IMMUNOLOGICAL STUDIES

Summary. The immunological and biochemical characteristics of murine megakaryocyte potentiator from lung and bone marrow were examined and compared with thrombopoietic stimulatory factor. Biological activity was not neutralized by anti‐erythropoietin, but megakaryocyte potentiator activity from all three sources was abolished or reduced when the preparations were treated with anti‐thrombopoietic stimulatory factor or anti‐interleukin‐6. Megakaryocyte potentiator levels in lung conditioned medium were not found to be enhanced from mice treated with lipopolysaccharide, in contrast to granulocyte‐macrophage colony‐stimulating factor (GM‐CSF) levels. The biochemical properties of murine megakaryocyte potentiator from lung and bone marrow were compared and found to be similar in the elution profiles from anion exchange, gel filtration and reversed phase liquid chromatography. It is concluded that the activities in lung and bone marrow are very similar if not identical, to interleukin‐6. Copyright © 1990, Wiley Blackwell. All rights reserved