慢性乙型肝炎患者外周血CD4+CD25+调节性T细胞的表达水平及临床意义

目的：观察抗病毒治疗前的慢性乙型肝炎(CHB)患者外周血CD4⁺CD25^high调节性T细胞（Treg）和CD4⁺CD25⁺CD127^low/-reg百分比和临床指标的相关性。方法：分离28例CHB患者和24例健康对照的外周血单个核细胞(PBMC)，以三色流式分析法分别对CD4⁺CD25^highTreg和CD4⁺CD25⁺CD127^low/-Treg进行分析。酶联免疫吸附试验(ELISA)检测HBsAg、HBsAb、HBeAg、HBeAb和HBcAb，实时荧光定量RT-PCR检测血清HBV DNA载量，同时进行肝功能检测。结果：CHB组CD4⁺CD25^highTreg和CD4⁺CD25⁺CD127^low/-Treg占CD4⁺T细胞的百分比分别为 3.36%±2.59% 和 4.05%±1.63% ，均高于正常对照组（1.60%±0.66%和1.75%±0.83%，P<0.01）。ALT大于100 U•L^-1的患者中CD4⁺CD25^highTreg占CD4⁺T淋巴细胞的百分比（4.26%±3.10%）高于ALT小于100U•L^-1的患者（2.52%±2.72% ，P<0.05）。CD4⁺CD25^highTreg占CD4⁺T淋巴细胞的百分比与ALT水平呈正相关（r=0.44，P<0.05）。结论：CHB患者体内CD4⁺CD25⁺Treg的升高可能抑制细胞免疫反应，影响病毒清除。CD25高表达水平易受转氨酶水平的影响，CD127用来作为调节性T细胞的鉴定更为可靠。

Expression levels of CD4+CD25+ regulatory T cells in peripheral blood of patients with chronic hepatitis B and clinical significance

Objective To investigate the proportion of CD4+CD25highTreg and CD4+CD25+CD127low/-Treg in peripheral blood in patients with chronic hepatitis B(CHB) and determine the relationship between the proportion of CD4+CD25+Treg and clinical parameters.Methods Fresh isolated peripheral blood mononuclear cells(PBMCs) of 28 patients with CHB and 24 healthy donors were analyzed for the proportion of CD4+CD25+Treg using flow cytometry by surface staining for CD4-PC5,CD25-FITC,CD127-PE.HBsAg,HBsAb,HBeAg,HBeAb and HBcAb were evaluated.HBV DNA levels were measured using real-time RT-PCR.Results The proportions of CD4+CD25highTreg to CD4+ T cells(3.36%±2.59%) and CD4+CD25+CD127low/-Treg(4.05%±1.63%) to CD4+ T cells in patients with CHB were higher than those in health controls(1.60%±0.66%,1.75%±0.83%,P<0.01) in peripheral blood.The CHB patients with high level alanine amino transferase(ALT)(ALT>100U·L-1) had a higher fraction(4.26%±3.10%) of CD4+CD25highTreg in peripheral blood than those patients with low level ALT(ALT<100U·L-1,2.52%±2.72%,P<0.05).The percentage of CD4+CD25highTreg was correlated with ALT level(r=0.44,P<0.05).Conclusion The level of Treg in CHB patients is higher than that in health controls.The expression of CD25 could be influenced by the level of ALT.As a specific cell surface marker,CD127 can be helpful to obtain pure CD4+CD25+Treg.