title: Blood and spleen haematopoiesis in patients with myelofibrosis.
abstract: Blood nucleated cells collected by leukapheresis and spleen cell suspension from patients with myelofibrosis with myeloid metaplasia (MMM) were studied for their haematopoietic capacity. Using committed progenitor cell assays (CFU-GM, BFU-e) and a one-stage long-term liquid stem cell system, we have shown: (1) a preferential expansion of the circulating committed progenitor cell pool above the more primitive stem cell compartment; (2) the absence of any development of a stromal adherent layer in long-term cultures of peripheral blood nucleated cells suggesting the self-sustaining capacity of the circulating primitive stem cells; (3) that the spleen is only a production site of committed progenitor cells but does not generate primitive stem cells; (4) the presence, in the spleen, of stromal progenitor cells. We conclude that the peripheral blood primitive stem cells in patients with MMM are not of splenic origin.
mesh_terms: D002478:Cells, Cultured; D006410:Hematopoiesis; D006411:Hematopoiesis, Extramedullary; D006412:Hematopoietic Stem Cells / Q000473:pathology; D006801:Humans; D007937:Leukapheresis; D010477:Perfusion; D055728:Primary Myelofibrosis / Q000097:blood* / Q000473:pathology; D013154:Spleen / Q000473:pathology / Q000502:physiology*; D013997:Time Factors