Heterogeneity of in vitro growth pattern of megakaryocyte progenitors (CFU-M) in myeloproliferative disorders.
In groups of 26 patients with myeloproliferative disorders (MPD), 8 with chronic myelogenous leukaemia (CML); 8 with polycythaemia vera (PV); 10 with essential thrombocythaemia (ET); and 6 patients with reactive thrombocytosis (RT), we studied the growth characteristics of bone marrow CFU-M in agar culture. The bone marrows from all the patients with MPD formed so called endogenous CFU-M colonies, in the absence of PHA-LCM, that increased in a dose-dependent manner with the addition of increasing concentrations of normal human AB-citrated plasma (NH-ABCP), while the bone marrows from all the patients with RT and from healthy controls formed few or no endogenous CFU-M colonies. In MPD, the endogenous CFU-M growth was enhanced by normal T cells in a dose-dependent fashion, and was decreased with the depletion of T cells from the marrow cells. These results suggest that the formation of endogenous CFU-M colonies is caused by hypersensitivity of CFU-M in MPD to NH-ABCP, which may contain a small amount of Meg-CSF, and/or by in vitro T cell stimulation. Among MPD, the endogenous CFU-M growth in ET was significantly lower than that of other MPD patients; however, the total number of ET CFU-M grown in the presence of PHA-LCM was the highest. These data show that the bone marrow CFU-M in MPD are heterogeneous with respect to in vitro growth pattern or sensitivity to exogenous Meg-CSF.
Hamaguchi
H
H
Third Department of Internal Medicine, Dokkyo University School of Medicine, Tochigi, Japan.
Takano
N
N
Sakamaki
H
H
Enokihara
H
H
Saito
K
K
Furusawa
S
S
Shishido
H
H
D002999:Clone Cells / Q000503:physiopathology; D003114:Colony-Forming Units Assay; D006801:Humans; D008533:Megakaryocytes / Q000473:pathology / Q000503:physiopathology; D009196:Myeloproliferative Disorders / Q000473:pathology*; D013234:Stem Cells / Q000473:pathology / Q000503:physiopathology; D013922:Thrombocytosis / Q000473:pathology