HBV转基因小鼠肝脏NKT细胞功能与PD1、CD28表达分析

目的研究HBV转基因小鼠肝脏中NKT细胞的功能与表面PD1、CD28表达的关系。方法分离小鼠肝脏、脾脏、胸腺和腹膜淋巴结单个核细胞,利用流式细胞检测技术,分别检测其淋巴细胞中NKT细胞的频率,同时检测肝脏NKT细胞PD1、CD28的表达及IFN-γ、IL-4的分泌功能,比较肝脏、脾脏、胸腺和腹膜淋巴结这几个主要免疫组织淋巴细胞中NKT细胞所占的比例,并分析肝脏NKT细胞PD1、CD28的表达与细胞功能的关系。结果与正常同品系小鼠比较,HBV转基因小鼠肝脏、脾脏、胸腺和腹膜淋巴结NKT细胞数量明显减少(P<0.05),与脾脏、胸腺和腹膜淋巴结相比,肝脏淋巴细胞中含有大量的NKT细胞;与正常同品系小鼠比较,HBV转基因小鼠肝脏NKT细胞PD1的表达明显增多(P<0.05),CD28的表达明显减少(P<0.05),肝脏NKT细胞IFN-γ、IL-4的分泌功能明显降低(P<0.05)。结论肝脏中含有大量的NKT细胞,HBV转基因小鼠肝脏NKT细胞的功能存在明显的缺陷,并提示PD1的增加和CD28的降低可能与NKT细胞功能的下调密切相关。

The function and the PD1 and CD28 expressions of hepatic NKT cells in HBV transgenic mice

It’s known that the costimulatory and coinhibitory signals appear to be important for NKT cell functions.In this study,we aimed to analyze the relationship of hepatic NKT cells functions with the expressions of PD1 and CD28 in HBV transgenic mice.We used flow cytometry to detect the frequencies of NKT cells in liver,spleen,thymus,and peritoneum lymph nodes from HBV transgenic mice and control mice.And flow cytometry was also used to detect the IFN-γ,IL-4,PD1,and CD28 levels of NKT cells in liver from HBV transgenic mice and control mice.Our data showed that the frequencies of NKT cells in liver,spleen,thymus,and peritoneum lymph node from HBV transgenic mice significantly decreased as compared to that in control mice(P< 0.05).The frequencies of NKT cells in liver were higher than that in spleen,thymus or peritoneum lymph nodes.Moreover,the NKT cells from HBV transgenic mic e demonstrated higher expression of the inhibitory receptor PD-1 but lower expression of the stimulant receptor CD28 as compared with the control mice(P< 0.05).Meanwhile,we also found that the frequencies of IFN-γ+ NKT cells and IL-4+ NKT cells in liver of HBV-transgenic mice was lower than those in control mice(P< 0.05).The data suggest that NKT cells are abundant in the liver and the NKT cell function is impaired in HBV transgenic mice.In addition,these findings also indicates that the NKT cells functional impairment may closely related with the inhibitory receptor PD-1 increase and stimulant receptor CD28 decrease.