经树突状细胞递呈的HBcAg特异性细胞毒T淋巴细胞的体外研究

Induction of hepatitis B virus core antigen-specific cytotoxic T lymphocytes by stimulation of dendritic cells with HBcAg in patients with chronic hepatitis B in vitro

目的 从人的外周血树突状细胞 (DC)的抗原递呈方面研究慢性乙型肝炎的发病机制 ,并诱导出针对HBcAg特异性的细胞毒T淋巴细胞 (CTL)。方法 取健康人DC和患者DC ,比较两组的抗原递呈功能是否存在差异。以HBcAg体外冲击致敏DC ,与自体T淋巴细胞共育 ,诱导出HBcAg特异性CTL ;以HepG2细胞为对照靶细胞 ,转染HBVDNA的HepG2 2 15细胞为靶细胞 ,分别测定CTL在效靶比为 2∶1、6∶1和 2 0∶1时对HepG2细胞的非特异性杀伤率及对HepG2 2 15细胞的特异性杀伤率 ,并比较患者组与正常组特异性杀伤率的差异。结果 患者DC的抗原递呈功能(10 99.2 6 7± 2 39.12 ,1374 .8± 36 4 .15 5 ,2 717.78± 15 89.72 )较健康人 (314 7.933± 72 6 .5 7,384 3.0 0 0±10 6 0 .85 ,5 4 86 .86 7± 1790 .6 4 )弱 ;健康组与患者组CTL对HepG2各效靶比的非特异性杀伤作用差异无显著性。健康组与患者组CTL对HepG2 2 15的特异性杀伤作用差异有显著性 ;患者组CTL的活性 (7.1± 4 .33,15 .6 8± 3.3,2 7.6 6± 4 .5 9)较健康组 (2 0 .76± 6 .0 8,33.97± 8.0 0 ,4 9.6 3± 9.4 8)弱。结论 用HBcAg体外负载患者DC ,能诱导出抗原特异性的CTL ,这些CTL能特异性地杀伤相应靶细胞。

Objective By inducing hepatitis B virus core antigen-specific cytotoxic T lymphocytes by stimulation of dendritic cells(DC), the relationship between pathogenesis and antigen present function of dendritic cells in patients with chronic HBV infection was investigated. Methods The DC from the healthy donors and patients were mixed with healthy allogeneic lymphocytes respectively to compare function between two groups DC. Then DC were pulsed with HBcAg in vitro and incubated with autologous lymphocytes to induce antigen specific CTL.The HBV DNA transfected hepatoma cells(2.2.15) were used as target cells for detecting the specific cytotoxicity of antigen-specific CTLs when the ratio of effector cell to target cell at 2∶1,6∶1, and 20∶1 respectively. Meanwhile, hepatoma cells (HepG2) were used as control target cells for detecting the nonspecific cytotoxity. Results DC of both groups could stimulate vigorous proliferations of allogenic lymphocytes. When DC numbers were the same,proliferation of lymphocytes from healthy donor group were 3147.933±726.57, 3843.000±1060.85, 5486.867±1790.64 at three different effector to target ratio,which were obviously stronger than those of patients(1099.267±239.12, 1374.8±364.155, 2717.78±1589.72). The cytotoxity of CTL to HepG2.2.15 in patients were 7.1±4.33, 15.68±3.3, 27.66±4.59,which were weaker than those of corresponding ratio of effector to target in the healthy controls(20.76±6.08, 33.97±8.00, 49.63±9.48). Conclusions DC from the patients challenged with HBcAg in vitro can induce antigen specific CTL which can kill the target cells specifically.