西罗莫司对K562细胞系及获得性纯红细胞再生障碍原代细胞红系分化作用的研究

Effect of sirolimus on erythropoiesis of K562 cell line and patients with pure red cell aplasia in vitro

目的明确西罗莫司体外对K562细胞系、获得性纯红细胞再生障碍（PRCA）患者骨髓单个核细胞向红细胞分化的影响。方法以K562细胞系及治疗前PRCA患者、正常对照的骨髓单个核细胞为研究对象，采用红系甲基纤维素培养基诱导其向红系分化，观察10、100、1000nmol／L西罗莫司对红细胞分化的影响。并进一步在PRCA原代细胞的培养体系中加入患者自身血清，观察各组红系爆式集落形成单位（BFU．E）的变化。结果不同浓度梯度西罗莫司对K562细胞系血红蛋白生成及红系表面抗原表达无明显影响；无论在正常对照还是PRCA患者骨髓单个核细胞中，西罗莫司处理组与未加药物的对照组比较，BFU—E差异无统计学意义；PRCA患者细胞加入自身血清后，其BFU—E较未加血清者明显减少[（76．40±22．48）个对（136．33±12．58）个，t=-4．329，P=O．001]，且患者细胞＋自身血清＋1000nmol／L西罗莫司组BFU—E[（97．14±15．83）个]明显高于患者细胞＋自身血清组（P=0．038）；，结论西罗莫司可能无直接刺激红细胞生长和分化作用，但可以拈抗患者血清对红细胞的抑制作用，可能通过抑制血清中的成分而起作用。

Objective To understand the effect of sirolimus on the erythropoiesis of K562 cell line and bone marrow cells from pure red cell aplasia （PRCA） patients and normal controls. Methods Different concentrations （10, 100, 1 000 nmol/L） of sirolimus were added to the K562 cell line or bone marrow cells from PRCA patients or normal controls and cultured 14 days for BFU-E formation. Meanwhile, sirolimus was also added to the serum treated PRCA bone marrow cells to cultivate for the same priod of time. Results Neither K562 cells, bone marrow cells from PRCA patients or normal controls showed any difference when sirolimus was added to the culture system for BFU-E. However, BFU- E formation decreased after serum was added in PRCA patients （76.40±22.48 vs 136.33±12.58, t = -4.329, P = 0.001） and this suppression of BFU-E was partly corrected by 1 000 nmol/L sirolimus treatment （97.14± 15.83 vs 76.40±22.48, P = 0.038）. Conclusions Sirolimus may modulate the suppression of erythropoiesis by serum instead of directly stimulate the growth of red blood cells in PRCA patients.