IL-21诱导自身免疫性肝炎患者促炎症细胞因子分泌

IL-21 induces the secretion of proinflammatory cytokines in patients with autoimmune hepatitis

目的:探讨IL-21在自身免疫性肝炎(AIH)发生过程中的免疫病理作用.方法:采集21例AIH患者和25例健康成人外周血样本,使用流式细胞仪检测PBMC表面IL-21R的表达.培养外周血单核淋巴细胞(PBMC),使用IL-21和抗CD3单抗刺激,使用ELISA检测上清液中TNF-α、IFN-γ和IL-2水平.结果:AIH患者外周血中CD4+、CD8+T细胞表达IL-21R水平比健康对照者显著升高(7.66%±2.37%vs3.12%±0.76%,9.42%±2.48%vs4.02%±0.89%,均P<0.05).体外培养PBMC,发现IL-21可显著诱导AIH患者PBMC分泌高水平的TNF-α、IFN-γ和IL-2(P<0.05).结论:AIH患者外周血T细胞表达IL-21R水平明显升高,并诱导T细胞分泌高水平的促炎症介质,提示IL-21参与了肝脏自身免疫损伤过程.

AIM： To detect the expression of IL-21 receptor （IL-21R） in peripheral blood mononuclear cells （PBMCs） from patients with autoimmune hepatitis （AIH） and analyze the secretion of proinflammatory cytokines （e.g., TNF-α, IFN-γ and IL-2） in cultured PBMCs stimulated with IL-21. METHODS： Peripheral blood samples were collected from 21 AIH patients and 25 healthy con- trols, respectively. The expression of IL-21Rin CD4^＋ and CD8^＋ T cells was examined by flow cytometry. After cultured PBMCs were stimulated with IL-21 and anti-CD3, the secretion of cytokines was examined by ELISA. RESULTS： IL-21R was significantly upregulated in CD4^＋ and CD8^＋ T cells （7.66% ± 2.37% vs 3.12% ± 0.76% and 9.42% ± 2.48% vs 4.02% ± 0.89%, respectively; both P 〈 0.05）. After stimulation with IL-21 and anti-CD3, the levels of secreted TNF-α, IFN-γ and IL-2 in PBMCs from AIH patients were significantly higher than those in PBMCs from healthy controls （P 〈 0.05）. CONCLUSION： IL-21R is highly expressed in T cells from AIH patients, and IL-21 is able to induce the secretion of proinflammatory cytokines, suggesting that IL-21 is involved in the process of tissue injury in AIH.