title: Inhibitory activity in human marrow plasma directed against mouse marrow cell proliferation: reduced in subjects with decreased granulopoiesis.
abstract: Human venous plasma is known to contain a lipoprotein-inhibitor of mouse marrow cell growth which we have found does not have cell type-specificity, in that it inhibits mouse lymphoma cell as well as marrow cell colony formation in vitro. Following its removal by CHCl3, we have identified residual inhibitory activity which reduces the growth of mouse marrow cells but not lymphoma cells. This inhibitory activity was found to be present in marrow and to much lesser extent in peripheral venous plasma obtained from subjects without disturbances in granulopoiesis. It was markedly reduced in subjects with disorders in which normal granulopoiesis was reduced, such as acute leukemia. The deficiency of this inhibitory activity in the marrow plasma of subjects with leukemia and related disorders may be due to a reduction in the cells from which it is derived (e.g. normal neutrophils or stromal cells), although further studies will be required to verify its presence and to determine its source and physiological role in granulopoiesis in man.
mesh_terms: D000818:Animals; D001853:Bone Marrow; D001854:Bone Marrow Cells; D002455:Cell Division; D046508:Culture Techniques; D006801:Humans; D008223:Lymphoma; D051379:Mice