抗原活化慢性乙型肝炎患者外周血树突状细胞的对比研究

Comparative study on dendritic cells stimulated with HBsAg or HBcAg in patients with chronic hepatitis B

目的探讨不同抗原在体外活化慢性乙型肝炎患者外周血树突状细胞（DC）及诱导特异性T细胞应答的能力。方法用无血清培养基从慢性乙型肝炎患者外周血中分离培养DC，在DC成熟前，分别加入HBsAg多肽、HBcAg多肽刺激，用流式细胞仪检测DC表型，用液闪计数仪观察DC对T细胞的增殖作用，用ELISA法检测混合淋巴细胞反应（MLR）中IL-12的分泌水平。结果经HBcAg多肽刺激DC的CD86表达率为（92．20±5．18）％，明显高于HBsAg多肽刺激组（76、19±3．90）％和未加抗原组（62、37±4．24）％，P〈0．01；经HBcAg多肽刺激组DC诱导同种异体静止T细胞增殖的能力每分钟液闪计数值cpm为34326±3088，明显高于HBsAg多肽刺激组20306±2897和单个核细胞组3454±409，P〈0、01；经HBcAg多肽刺激组DCMLR中IL-12（348±42、8）ng／L，分别高于HBsAg多肽刺激组（226±30、6）ng／L和未加抗原组（116±15．6）ng／L，P〈0．01。结论使用HBcAg多肽刺激DC可比HBsAg多肽更有效地提呈病毒抗原，提高诱导特异性T细胞应答的能力。

Objective To study activation of dendritic cells （DC） isolated from peripheral blood monocytes of patients with chronic hepatitis B after stimulation with HBsAg or HBcAg. Methods DCs were isolated from peripheral blood monocytes of patients with chronic hepatitis B. DCs were impulsed with HBsAg and HBcAg separately before their maturation. The expression levels of DC surface molecule were analyzed by using flow cytometry and the ability of DC to induce T lymphocyte proliferation was evaluated by a liquid scintillation counter and the amount of interleukin-12 （IL-12） in mixed lymphocytic reaction （MLR） was measured by using ELISA. Results The expression rate of CD86 significantly increased to （92.20 ± 5.18）% on DC after loading with HBcAg as compared with those after loading with HBsAg （76.19 ± 3.90） % and controls （62.37 ± 4.24） % , P 〈 0.01. The ability of DC after loading with HBcAg to induce T lymphocyte proliferation （34 326 ± 3088 cpm） was significantly higher than that of DC after loading with HBsAg （20 306 ± 2897 cpm） and controls （3454 ± 409 cpm）, P 〈 0.01. The amount of IL-12 in MLR of DC after loading with HBcAg was （348 ± 42.8） ng/L, which was significantly higher than those of DC after loading with HBsAg （226 ± 30.6） ng/L and controls （116 ± 15.6） ng/L, P 〈 0.01. Conclusions Human dendritic cell stimulated with HBcAg could more efficiently present antigen and induce specific T cell immune response.