抗c-mpl抗体在系统性红斑狼疮并发血小板减少中的作用

目的:分析抗血小板生成素(thrombopoietin,TPO)受体(c-mpl)抗体在系统性红斑狼疮(systemic lupuserythematosus,SLE)血小板减少中的作用,探讨该抗体的致病机制及临床价值。方法:应用间接ELISA法检测24例伴血小板减少SLE患者(A组)、27例曾有血小板减少现已恢复正常SLE患者(B组)、18例无血小板减少SLE患者(C组)及18例正常对照者血清中抗c-mpl抗体、TPO水平,分析其与临床表现及SLE疾病活动性指数(SLEdisease activity index,SLEDAI)之间的关系。结果:血清抗c-mpl抗体在SLE总的阳性率为18.8%,抗c-mpl抗体在A组、B组和C组中的阳性率差异无统计学意义(P=0.600)。抗c-mpl抗体阳性组血小板计数明显低于阴性组(P=0.025),血清TPO水平明显高于阴性组(P=0.038),抗c-mpl抗体阳性与阴性组补体C3和C4、红细胞沉降率(erythrocyte sedimentation rate,ESR)、C反应蛋白(C-reactive protein,CRP)及抗核抗体(anti-nuclear antibody,ANA)、抗双链DNA抗体(anti double-strained DNA,dsDNA)、抗中性粒细胞胞浆抗体(antineutrophil cytoplasmic antibody,ANCA)阳性率、SLEDAI评分差异均无统计学意义(P>0.05)。结论:抗c-mpl抗体可能通过与TPO竞争结合c-mpl,阻断TPO-c-mpl通路,引起巨核细胞分化、发育、成熟障碍,从而引起血小板减少。

Role of anti c-mpl antibody in systemic lupus erythematosus with thrombocytopenia

Objective:To determine whether anti-thrompoietin receptor(TPO-R,c-mpl) antibody contributes to thrombocytopenia in systemic lupus erytematosus(SLE) and explore the pathogenic role of this antibody.Methods: Sera from 24 SLE patients with thrombocytopenia,27 SLE patients having normal platelet counts with a history of thrombocytopenia,18 SLE patients with neither thrombocytopenia nor post thrombocytopenia and 18 healthy controls were collected.Anti c-mpl antibodies were detected by an indirected ELISA assay.The serum TPO levels were measured by an ELISA assay.Clinical findings,autoantibody profiles,and SLEDAI were evaluated.Results: Serum anti c-mpl antibodies were detected in 18.8% of the SLE patientis.The frequency of this antibody in SLE with thrombocytopenia,SLE with a history of thrombocytopenia and SLE without thrombocytopenia were of no difference(P=0.600).In the patients with anti c-mpl antibodies,their platelet counts were decreased(P=0.025) and serum TPO levels elevated(P=0.038) than those in the patients without,while there were no differences between the two groups in C3,C4,ESR,CRP level,the frequency of ANA,dsDNA,ANCA and SLEDAI.Conclusion: Anti c-mpl antibody contributes to SLE-associated thrombocytopenia by functionally blocking an interaction between thrombopoietin and c-mpl,which might inhibit TPO-dependent megakaryocyte proliferation and differentiation.