系统性红斑狼疮血小板减少患者血清抑制巨核细胞倍体形成

Suppressive effect of sera from patients with systemic lupus erythematosus associated with thrombocytopenia on megakaryocyte polyploidy

目的研究系统性红斑狼疮(SLE)合并血小板减少病人的血清对正常人骨髓巨核细胞倍体形成的影响,了解SLE血小板减少病人的血清对正常巨核细胞产生血小板的能力有无抑制作用。方法12例SLE血小板减少病人为研究对象,正常骨髓细胞来源于胸外科手术切除的肋骨(胸外伤或食管裂孔疝患者),骨髓细胞体外培养,并分别加入12例SLE血小板减少病人的血清、灭活补体的病人的血清和SLE血小板正常病情活动病人的血清,流式细胞仪分析检测培养细胞中CD41+细胞(巨核细胞)的倍体分布。结果正常人骨髓细胞培养后,2倍体、4倍体和8倍体的巨核细胞数分别为(37.8±5.4)%、(29.8±3.3)%和(2.61±0.63)%;加入SLE血小板减少病人的血清后4倍体和8倍体细胞明显受到抑制,分别为(15.91±2.65)%和(0.44±0.12)%,P<0.05。灭活血清中的补体后,这种抑制作用仍然存在。与10%浓度的SLE血小板减少病人血清相比,20%的血清则几乎完全抑制了8倍体和4倍体细胞的形成。结论SLE血小板减少病人血清存在某种抑制物,抑制正常人高倍体巨核细胞的形成,这种抑制作用是非补体依赖的,并与剂量相关。

Objective To study the effects of sera from patients with systemic lupus erythematosus (SLE) associated with immune thrombocytopenia on megakaryocyte polyploidy. Methods Twelve patients with SLE associated with immune thrombocytopenia and 12 cases of SLE patients who had never had thrombocytopenia but in active phase were included in this study. Sera were obtained from all subjects and the complements were inactivated. Bone marrow mononuclear cells from normal control were cultured in vitro in the presence of combination of thrombopoietin (TPO) and interleukin-3 (IL-3) and interleukin-6 (IL-6) and then sera sample were also added into culture system. Ploidy distribution were observed by a double-staining technique and flow cytometry. Results Suppressive effects of sera from SLE patients associated with thrombocytopenia on ploidy distribution of cultured normal CD41+ cells were observed . Only (15.9±2.6)% of 4 N class and (0.44±0.12)% 8 N class ploidy were found after adding sera from SLE patients associated with immune thrombocytopenia into culture system, compared to (29.8±3.3)% of 4 N class and (2.61±0.63)% of 8 N class in normal control, respectively. Suppressive effects of ploidy distribution were not disappeared when complements in the sera were inactivated. Almost no 8 N or 4 N class of ploidy was observed when 20% of the sera were added into culture system, compared to 10% of sera. Conclusion These data suggest that an inhibitor of ploidy distribution to normal bone marrow megakaryocyte may exist in sera of SLE patients associated with immune thrombocytopenia. This suppressive effect on ploidy distribution is mediated neither by monocytes, lymphocytes nor complements.