高迁移率族蛋白B1及Toll样受体4在儿童系统性红斑狼疮中的临床意义

Clinical significance of high mobility group protein B1 and Toll-like receptor 4 in children with systemic lupus erythematosus

目的探讨高迁移率族蛋白B1(HMGB1)和Toll样受体4(TLR-4)在儿童SLE外周血清水平表达与临床意义。方法ELISA法测定33例SLE患儿外周静脉血标本和10名健康对照组血清中HMBG1表达情况;反转录(RT)-PCR技术检测PBMCsHMGB1-mRNA的表达情况;流式细胞术检测SLE患儿外周血单核细胞膜表面CD14/TLR-4表达情况。2组间HMGBI水平比较采用单因素方差分析,相关分析采用Pearson、Logistic回归分析。结果外周血HMGB1水平和HMGB1-mRNA表达量在SLE活动组患儿中[(25.8±3.9)ng/ml,0.80±0.16]明显高于稳定组[(9.3±2.7)ng/ml,0.46±0.18,F=7.0,2.8,P<0.05]和健康对照组[(9.1±0.9)ng/ml,0.34±0.10,F=50.2,7.5,P<0.05];外周血单核细胞膜表面CD14/TLR-4表达情况在SLE活动组患儿(91.2±1.3)中高于稳定组[(87.6±2.8),F=0.8,P<0.05]和健康对照组[(87.0±2.2),F=0.9,P<0.05];SLE患儿外周血HMGB1表达情况检测和单核细胞膜表面CD14/TLR-4的检测表达情况呈正相关(r=0.48,P<0.01);SLE患儿尿蛋白含量和HMGB1浓度呈正相关(r=0.48,P<0.01),而在稳定组和健康对照组中,HMGB1与CD14/TLR-4和尿蛋白含量均无明显相关性,这说明HMGB1在细胞膜外可能通过CD14/TLR-4受体参与了儿童SLE发病。结论SLE患儿PBMCs能分泌HMGB1,使外周血清中HMGB1水平增高,且可能通过CD14/TLR4途径参与SLE肾脏损害。

Objective To investigate the expression levels of peripheral blood and clinical signifi-cance of High mobility group protein B1 (HMGB1) and toll-like receptor 4 (TLR-4) in children with systemic lupus erythematosus (SLE). Methods Enzyme-linked immuno sorbent assay (ELISA) was used to deter-mine the HMGB1 levels in the serum of peripheral venous blood samples from 33 SLE patients and 10 healthy children. RT-polymerase chain reaction (PCR) technique was used to detect the HMGB1-mRNA expression in the mononuclear cells of peripheral blood. Flow cytometry was adopted to detect the CD14/TLR-4 on the surface of mononuclear cell membrane in the peripheral blood of active SLE patients. One-way analysis of variance (ANOVA) was used to compare HMGB1 levels between the two groups. Pearson correlation and Logistic regression were used for correlation analysis. Results ① The levels of HMGB1 and HMGB1 mRNA in the peripheral blood of SLE active patients [(25.8±3.9) ng/ml and (0.80±0.16) respectively] were signifi-cantly higher than the stable group [(9.3±2.7) ng/ml and (0.46±0.18) respectively, F=7.0, 2.8, P<0.05] and healthy children [(9.1±0.9) ng/ml and (0.34±0.10) respectively, F=50.2, 7.5, P<0.05].② The CD14/TLR-4 expressions on the surface of mononuclear cell membrane in the peripheral blood of SLE active patients (91.2±1.3) were significantly higher than the stable group [(87.6±2.8), F=0.8, P<0.05] and the healthy children [(87.0±2.2), F=0.9, P<0.05].③ There was significant positive correlation (r=0.48, P<0.05) between the levels of HMGB1 and CD14/TLR-4 in different SLE patients. In addition, the levels of HMGB1 were also positively correlated (r=0.48, P<0.01) with the detected concentrations of urinary protein in SLE patients. However, in the stable and healthy groups, there was no correlation between HMGB1 and CD14/TLR-4 and urinary protein. These indicate that HMGB1 outside the cell membrane were involved in SLE morbidity in children through TLR-4. Conclusion The mononuclear cells in peripheral blood of children with SLE can secrete HMGB1, which could lead to the increase of HMGB1 level in the serum of peripheral blood, and possibly participate in kidney damage of SLE through CD14/TLR-4.