慢性丙型肝炎患者病毒载量与滤泡辅助性T淋巴细胞表面CD226表达的关系

Relationship between viral load and expression of CD226 on the surface of T follicular helper cells in patients with chronic hepatitis C

目的探讨慢性丙型肝炎（chronic hepatitis C, CHC）患者病毒载量与滤泡辅助性T淋巴细胞（T follicular helper cells, Tfh）表面CD226表达的关系。方法无锡市第五人民医院2015年3月至2017年4月就诊的CHC患者135例，另取30名健康献血员作为健康对照组。根据HCV RNA水平分为低病毒载量组49例（36.3%）和高病毒载量组86例（63.7%），比较两组患者的外周血Tfh表面CD226表达、Tfh、IL-21和HCV特异性CTL水平。计数资料比较采用χ2检验，计量资料比较采用t检验，不同因素相关性分析采用Pearson方法。结果135例CHC患者的外周血Tfh表面CD226表达水平为（77.69±5.42） %，低于健康对照组的（90.06±5.83） %，两组比较差异有统计学意义（t＝7.541，P〈0.01）；低病毒载量组的外周血Tfh表面CD226表达水平为（88.75±6.68） %，高于高病毒载量组的（69.23±5.86） %，两组比较差异有统计学意义（t＝19.232，P〈0.01）。病毒载量与Tfh表面CD226表达水平呈负相关（r＝－0.705，P〈0.01）。135例CHC患者的外周血Tfh水平高于健康对照组，两组比较差异有统计学意义（t＝13.878，P〈0.01）；低病毒载量组外周血Tfh水平高于高病毒载量组，两组比较差异有统计学意义（t＝26.993，P〈0.01）。135例CHC患者的IL-21水平低于健康对照组的（70.35±1.6）ng/L，两组比较差异有统计学意义（t＝18.322，P〈0.01）；低病毒载量组的外周血IL-21水平高于高病毒载量组，两组比较差异有统计学意义（t＝84.54，P〈0.01）。低病毒载量组外周血HCV特异性CTL水平高于高病毒载量组，两组比较差异有统计学意义，（t＝29.869，P〈0.01）。病毒载量与HCV特异性CTL水平呈负相关（r＝－0.734，P〈0.01）。结论CHC患者中，不同病毒载量导致Tfh表面CD226表达水平不同；低病毒载量者可引起Tfh表面CD226表达水平升高，从而进一步导致Tfh、IL-21及HCV特异性CTL的表达水平升高。

ObjectiveTo explore the relationship between viral load and expression of CD226 on the surface of peripheral blood T follicular helper cells （Tfh） in patients with chronic hepatitis C （CHC）.MethodsOne hundred and thirty-five CHC patients hospitalized at Wuxi Fifth People′s Hospital from March 2015 to April 2017 were collected, and another 30 healthy blood donors were set as healthy control group. CHC patients were divided into two groups based on hepatitis C virus （HCV） RNA level, with 49 cases （36.3%） in low viral load group and 86 cases （63.7%） in high viral load group. Expression of CD226 on the surface of peripheral blood Tfh cells, Tfh cells, interleukin （IL）-21 and HCV specific cytotoxic lymphocyte （CTL） levels of two patient groups were compared. Categorical data were compared with chi-square test and normally distribute continuous data were compared with t test. Correlations between different factors were analyzed by Pearson correlation analysis.ResultsExpression of CD226 on the surface of peripheral blood Tfh cells in 135 cases of CHC patients was （77.69±5.42）%, which was lower than that of healthy control （[90.06±5.83]%）, and the difference between the two groups was significant （t=7.541, P〈0.01）. The CD226 expression on the peripheral blood Tfh cells in low viral load group was （88.75±6.68）%, which was higher than that of high viral load group （[69.23±5.86]%）, and the difference between the two groups was significant （t=19.232, P〈0.01）. The viral load was negatively correlated with Tfh cell surface CD226 expression （r=-0.705, P〈0.01）. The peripheral blood Tfh cell level in 135 CHC patients was higher than that of healthy control, and the difference between the two groups was significant （t=13.878, P〈0.01）. The peripheral blood Tfh cell level in low viral load group was higher than that in high viral load group, and the difference between the two groups was significant （t=26.993, P〈0.01）. The IL-21 level of 135 CHC patients was lower than that of healthy control （[70.35±1.6]%）, and the difference between the two groups was significant （t=18.322, P〈0.01）. The IL-21 level in peripheral blood of low viral load group was higher than that of high viral load group, and the difference between the two groups was significant （t=84.54, P〈0.01）. HCV specific CTL level in peripheral blood of low viral load group was higher than that of high viral load group, and the difference between the two groups was significant （t=29.869, P〈0.01）. The viral load was negatively correlated with levels of HCV specific CTL （r=-0.734, P〈0.01）.ConclusionsIn patients with chronic hepatitis C, different levels of viral load can result in different levels of CD226 expression on the peripheral blood Tfh cells. Patients with low viral load has high CD226 expression on Tfh cell surface, resulting in rise of Tfh cell level, IL-21 level and HCV specific CTL level.