过敏性紫癜患者外周血白细胞B7-H1及其受体PD-1分子的表达

B7-H1 and PD-1 expressions on peripheral leukocytes from patients with Henoch-Schonlein purpura

目的探讨过敏性紫癜患者外周血白细胞B7－H1和PD－1分子的表达及其意义。方法应用荧光抗体染色技术经流式细胞仪检测36例过敏性紫癜患者和24例正常人对照外周血白细胞表面的B7－H1及PD－1分子的表达水平，并比较两者在过敏性紫癜患者与正常人对照之间以及在伴紫癜性肾炎组患者和非紫癜性肾炎组患者之间的表达水平差异。结果过敏性紫癜患者组B7－H1及PD－1在单核细胞上的阳性表达率分别为24．43％±25．79％，0．84％±1．96％；正常人对照组分别为7．69％±8．31％、2．28％±1．95％。过敏性紫癜患者组外周血单核细胞B7－H1表达水平显著高于正常人对照组（t=3．62，P〈0．01），而PD—1表达水平则显著低于正常人对照组（t=2．78，P〈0．01）。患者组和对照组淋巴细胞表面B7－H1及PD－1的表达差异无统计学意义，P值均〉0．05。过敏性紫癜患者中伴肾炎组患者B7－H1在单核细胞及淋巴细胞上的阳性表达率分别为44．81％±12．36％，8．78％±2．10％；无肾炎组分别为17．63％±25．63％，5．65％-4-3．96％；伴肾炎患者单核细胞及淋巴细胞的B7－H1的表达水平均显著高于无肾炎患者，t=3．05，2．25，P值〈0.01或0．05。结论过敏性紫癜患者外周血单核细胞表面B7－H1表达升高，而PD—1表达下降，B7－H1与PD－1可能在过敏性紫癜发病机制中发挥一定作用。

Objective To investigate the expressions of B7-H1 and PD-1 on peripheral leukocytes from patients with Henoch-Schonlein purpura （HSP） and their significance. Methods Peripheral leukocytes were obtained from 36 patients with HSP （HSP group） and 24 healthy human controls （control group）. Immunofluorescent staining and flow cytometry were used to measure the expressions of B7-H1 and PD-1 on periphei-al leukocytes. The expression of both two molecules was compared between the HSP group and control group as well as between patients with Henoch-Schonlein purpura nephritis （HSPN） （n = 9） and those without （n = 27）. SPSS 12.0 for Windows was used for data analysis. Results The expression rate of B7-H1 on monocytes significantly increased （24.43% ± 25.79% vs 7.69% ± 8.31%, t = 3.62, P 〈 0.011）, while that of PD-1 decreased （0.84% ± 1.96% vs 2.28% ± 1.95%, t = 2.78, P 〈 0.01 ） in HSP group compared with those in the control group. No significant difference was revealed in the expression of B7-H1 or PD-1 on lymphocytes between HSP group and control group （both P 〉 0.05）. There was a significant increase in the expression of B7-H1 on monocytes （44.81% ± 12.36% vs 17.63% ± 25.63%, t = 3.05, P 〈 0.01） and lymphocytes （8.78% ± 2.10% vs 5.65% ± 3.96%, t = 2.25, P 〈 0.05） in patients with HSPN compared with those without. Conelusiort There is a high expression of B7-H1, but low expression of PD-1 on peripheral blood monocytes from patients with HSP, suggesting that B7-H1 and PD-1 may play a certain role in the pathogenesis of HSP.