乙型肝炎肝硬化患者外周血T细胞PD-1和PD-L1表达水平及意义

目的探讨乙型肝炎肝硬化患者外周血T淋巴细胞程序性死亡分子-1(PD-1)及其主要配体PD-L1的表达情况。方法在50例乙型肝炎肝硬化患者和25例健康体检者,使用流式细胞仪检测外周血T细胞PD-1和PD-L1表达;采用荧光定量核酸扩增及测序法检测血清HBV DNA载量。结果对照组和肝硬化组外周血T细胞PD-1阳性表达率分别为11.93±1.23%和33.13±3.38%(P<0.05),PD-L1阳性表达率分别为10.59±1.88%和32.47±2.18%(P<0.05);Child-Pugh A级(30.58±2.99%和32.19±1.44%)、B级(34.61±1.43%和33.46±2.58%)和C级(34.2±2.31%和31.76±2.33%)患者外周血T细胞PD-1和PD-L1表达率无显著性相差(P>0.05);在肝硬化患者,T细胞表面PD-l和PD-Ll表达水平与血清HBV DNA载量呈明显正相关(r2=0.8326和:r2=0.643,P<0.05)。结论肝硬化患者外周血T细胞PD-1和PD-L1表达水平明显上调,且与血清HBV DNA载量呈明显正相关,提示T细胞高表达的PD-1可能通过与其配体PD-L1作用而抑制T细胞免疫应答,并导致病毒感染持续。

Programmed death-1 and its ligand-1 expression of peripheral blood T lymphocytes in patients with hepatitis B-related liver cirrhosis

Objective To evaluate the programmed death-1（PD-1） and its ligand-1（PD-L1） expression of peripheral blood T lymphocytes in patients with hepatitis B-related liver cirrhosis.Methods 50 patients with hepatitis B liver cirrhosis were selected,and 25 healthy persons were also selected as control.Their blood samples were detected for the percentages of PD-1＋ and PD-L1＋ of CD3＋T cells by flow cytometry.HBV DNA load were determined by real-time fluorescent quantitative PCR method.Results The percentage of PD-1＋ in healthy controls and in patients with liver cirrhosis were 11.93±1.23% and 33.13±3.38%（P0.05）,and those of PD-L1＋ were 10.59±1.88% and 32.47±2.18%（P0.05）,respectively;The percentage of PD-1 and PD-L1 in patients with Child-Pugh class A（n=16）,B（n=21）andC（n=13） were 30.58±2.99% and 32.19±1.44%,34.61±1.43% and 33.46±2.58%,and 34.2±2.31% and 31.76±2.33%（P0.05）,respectively;The expression of PD-1＋ and PD-L1＋ in patients with liver cirrhosis was positively correlated with serum HBV DNA load（PD-1：r2=0.8326 and PD-L1：r2=0.643,respectively）.Conclusion The T lymphocyte expression of PD-1＋ and PD-L1＋ is obviously up-regulated in patients with liver cirrhosis,which might take a part in the pathogenesis.