紫癜性肾炎患儿外周血白三烯B4水平和CD4+CD25+调节性T细胞表达

摘要

目的 观察紫癜性肾炎(HSPN)患儿白三烯B4(LTB4)、CD4+CD25+调节性T细胞(regulatory T cell,Treg)表达及其相关性,探讨两者在过敏性紫癜(HSP)肾损害中的作用.方法 选择HSP患儿20例,HSPN患儿40例,健康对照者20例.采用ELISA法检测各组血浆LTB4水平,流式细胞术检测各组外周血CD4+CD25+Treg比例,比色法测定24 h尿蛋白(24 hUpro)含量.HSPN患儿中25例行肾组织活检.结果 (1)HSPN组血浆LTB4水平高于HSP组和对照组(P＜0.05),HSP组亦高于对照组(P＜0.05);(2)HSPN组外周血CD4+CD25+Treg比例低于HSP组和对照组(P＜0.05),HSP组亦低于对照组(P＜0.05);(3)HSP患儿血浆LTB4水平与CD4+CD25+Treg比例呈负相关(r=-0.74,P＜0.05);(4)HSPN组血浆LTB4水平与病理分级、24 h Upro呈正相关(r=0.89,0.91,P＜0.01);CD4+CD25+Treg比例与病理分级、24 h Upro呈负相关(r=-0.95,-0.82,P＜0.01).结论 HSPN患儿血浆LTB4水平升高、CD4+CD25+Treg数量减少,二者相互作用参与并促进了HSPN的发生、发展.%Objective To investigate the variation and correlation between leukotriene B4 (LTB4), and CD4+CD25+ regulatory T cell (Treg) in childen with Henoch-Schonlein purpura nephritis (HSPN), and explore their effects on kidney lesion in childen with Henoch-Schonlein purpura(HSP). Methods 20 cases with HSP,40 cases with HSPN and 20 normal controls were enrolled. ELISA was used to measure the level of LTB4. Flow cytometric analysis(FCM) was performed to detect the percentage of CD4+CD25+ Treg subpopulation. 24 h urine protein excretion was detected with colorimetric method in these children. Results (1)The level of plasma LTB4 increased significantly in HSPN children compared with control group or HSP children (p＜0. 05),and that of HSP children were also higher than control groups (2)The ratio of CD4+CD25+Treg was significantly lower in peripheral blood of HSPN children than control group or HSP children (P＜0. 05) sand that of HSP children was also lower than control group ; (3)The level of LTB4 in HSP children correlated negatively with CD4+CD25+ Treg(γ=-0. 74,P＜0. 05); (4)In HSPN children,the level of LTB4 correlated positively with renal pathologic grade and 24 h urine protein (γ=-0. 89,0. 91 ,P＜0.01) ； the ratio of CD4+CD25+Treg correlated negatively with renal pathologic grade and 24 h urine protein (γ= -0. 95, -0. 82,P＜0. 01). Conclusion The increased expression of LTB4 and decreased expression of CD4+CD25+ Treg might participate and promote the formation and development of HSPN.