慢性乙型肝炎病毒感染不同免疫状态正负共刺激分子表达的研究

Research on co-stimulatory and co-inhibitory molecules of patients with chronic hepatitis B virus infection at different immune stages

目的探讨慢性乙型肝炎病毒(HBV)感染患者不同免疫状态下正负共刺激分子表达的意义。方法用半定量逆转录聚合酶链反应(RT-PCR)法研究30例免疫清除期患者、10例免疫耐受期患者和10例健康对照者外周血单个核细胞B7-2及程序性死亡配体-1(PD-L1)mRNA的表达水平。结果免疫清除期和免疫耐受期患者B7-2的表达水平明显低于健康对照组(P均<0.01);免疫清除期患者B7-2的表达水平明显低于免疫耐受期患者(P<0.01)。免疫清除期和免疫耐受期患者PD-L1的表达水平和PD-L1/B7-2比值均明显高于健康对照组(P均<0.01);免疫清除期和免疫耐受期患者PD-L1的表达水平差异无统计学意义(P>0.05),免疫清除期患者PD-L1/B7-2比值明显高于免疫耐受期患者(P<0.01)。结论在慢性乙型肝炎的发病中,正、负共刺激分子的变化可能是机体对免疫反应的保护性调节的结果,最终可能使机体对HBV的免疫耐受加深。

Objective To explore the roles of co-stimulatory and co-inhibitory molecules in patients with chronic hepatitis B virus（HBV） infection at different immune stages. Methods Thirty patients with chronic HBV infection in their immune active stage, 10 patients in their immune tolerant stage were enrolled in this research, and 10 healthy people were used as controls. Reverse transcription polymerase chain reaction（RT-PCR） was applied to detect the expression level of co-stimulatory molecule B7-2 and programmed death ligand-1 （ PD-L1 ） mRNA in peripheral blood mononuclear cells. Results It showed that B7-2 level of patients with chronic HBV infection in immune active stage and immune tolerant stage was significantly lower than that of the controls（ P 〈 0.01 ） ; B7-2 level of patients in immune active stage was significantly lower than that of patients in immune tolerant stage（P 〈0. 01 ）. PD-L1 expression level and PD-L1/B7-2 ratio of patients in immune active stage and immune tolerant stage were significantly higher than those of the healthy controls（ all P 〈0. 01 ）. PD-L1/ B7-2 ratio in immune-active patients was significantly higher than that in immune-tolerant patients （P 〈 0. 01 ）. Conclusion In chronic HBV infection patients, the changed expression level of eo-stimulatory and co-inhibitory molecules implies a protective adjustment against immune response which subsequently results in increased immune tolerance.