Study on the regulation mechanism of megakaryocyte and thrombo-cytopoiesis

原发性血小板增多症（ET）和真性红细胞增多症（PV）的巨核细胞生成为了研究ET和PV的巨核细胞生成和血小板生成异常，我们在含有人血浆的甲基纤维素体系中培养骨髓巨核细胞祖细胞（CFU-MK）。大多数ET患者和大约三分之二的PV患者在缺乏刺激剂（PHA-LCM）的情况下显示自发性CFU-MK集落生长。ET和PV组的CFU-MK数量明显高于对照组。与对照组相比，来自ET和PV的CFU-MK每个集落产生的巨核细胞数量更多。在PV患者中，自发性CFU-MK患者与骨髓活检标本上巨核细胞数量增加和血小板增多有关。反应性血小板增多的患者没有自发的CFU-MK生长，与对照组相似。这些数据表明，巨核细胞数量的异常增加和由此导致的红细胞增多，至少部分原因是由于这种异常的CFU-MK群体（自发性CFU-MK；自主或对刺激物高度敏感的群体）。反应性血小板增多可能是由于对cfu - mk后室的一些刺激（可能是由于血小板生成素增加）。多种纯生长因子对小鼠巨核细胞生成的影响促红细胞生成素和IL-3对小鼠体外巨核细胞生成的影响已被证实。这次我们在体外和体内研究了GM-CSF（小鼠重组物）对小鼠巨核细胞生成的影响。同时研究了IL-6（人，重组）的作用。GM-CSF刺激CFU-MK以及CFU-GM菌落形成的血清耗尽琼脂培养。GM-CSF还能增加巨核细胞的大小和液体培养巨核细胞的乙酰胆碱酯酶活性。直接使用单个巨核细胞，不论有无GM-CSF，均可发现这种效果。体内注射（1 ug，每天2次，每只小鼠，连续6天），粒细胞增加2倍。骨髓中CFU-MK数及血小板水平无明显变化。使用相同的培养系统，发现UL-6可以促进小鼠巨核细胞的成熟，但不能促进其增殖。效果是直接的。IL-6在体内的作用还有待研究。少

Megakaryocytopoiesis in essential thrombocythemia (ET) and polycythemia vera (PV)To characterize abnormal megakaryocytopoiesis and thrombopoiesis in ET and PV, bone marrow megakaryocytic progenitors (CFU-MK) were cultured in a methylcellulose system containg human plasma. Most of the ET patients and about two-thirds of the PV patients studied revealed spontaneous CFU-MK colony growth in the absence of stimulator (PHA-LCM). The number of CFU-MK in ET and PV was significantly increased than that of the control subjects. CFU-MK from ET and PV gave rise to larger number of megakaryocytes per each colony compared to the control subjects. Among PV pateints, those who showed spontaneous CFU-MK were associated with an increased megakaryocyte number number on marrow biopsy specimen and thrombocytosis. Patients with reactive thrombocytosis showed no spontaneous CFU-MK growth, similar to the contro subjects. The data suggested that the abnormally incresed number of megakaryocytes and resultant th … More rombocytosis is, at least partly, due to such abnormal CFU-MK population (spontaneous CFU-MK; autonomous or highly sensitive population to the stimulator). Reactive thrombocytosis may be due to some stimuli on post-CFU-MK compartment (possibly due to incresed thrombopoietin).Efect of various pure growth factors on murine megakaryocytopoiesisThe effects of erythropoietin and IL-3 on murine megakaryocytopoiesis in vitro have been previously demonstrated. This time, we studied the effect of GM-CSF (mouse recombinant) on murine megakaryocytopoiesis in vitro and in vivo. The effect of IL-6 (human, recombinant) was also studied.GM-CSF stimulated CFU-MK as well as CFU-GM colony formation in serum depletedagar culture. GM-CSF also increased the size of megakaryocytes and acetylcholinesterase activity of megakarocytes in liquid culture. The effect was found direct using a single megakaryocyte cylture with or without GM-CSF. When injected in vivo (1 ug twice a day, each mouse, for 6 days), two fold increase of granuloctes was observed. CFU-MK numbers in bone marrow and platelet level were not changed.Using the same culture systems, UL-6 was found to promote the maturation but not proliferation of murine megakaryocytes. The effect was direct. The in vivo role of IL-6 remains to be studied. Less