隐球菌脑膜炎患者外周血CD200表达水平及其临床意义

Expression Level and Clinical Significance of CD200 in Peripheral Blood for Patients with Cryptococcal Meningitis

目的分析隐球菌脑膜炎患者外周血CD200的表达水平及其与其他炎性因子水平的关系。方法选取2009年6月～2013年11月期间上海长海医院和长征医院收治的25例隐球菌脑膜炎患者为研究对象，归为观察组，同时选取同期来体检的30名健康成人作为对照组。收集受试者的外周抗凝血，分离外周单个核细胞（PBMc），采用反转录酶-聚合酶链锁反应（RT—PCR）方法检测PBMC中CD200的mRNA水平，采用酶联免疫吸附试验（ELISA）方法检测其血浆CD200蛋白水平以及TNF-α，IFN-γ和IL-17的水平，并采用Pearson相关分析探讨CD200与这些炎性因子的相关性。结果观察组和对照组PBMC的CD200mRNA水平分别为1．73±0．51和1．69±0．47，两组比较差异无统计学意义（P〉0．05）。观察组血浆cD200蛋白水平为212．3±70．5pg／ml，显著高于对照组的90．5±32．2pg／ml，差异有统计学意义（P〈0．05）。观察组血浆TNF-a，IFN-γ水平显著低于对照组，IL-17水平显著高于对照组，差异具有统计学意义（P〈0．05）。Pearson相关分析结果提示血浆CD200水平与IFN-γ呈负相关（r=-0．635，P〈0．001），与IL-17水平呈正相关（r=0．668，P〈0．001）。结论隐球菌脑膜炎患者血浆CD200水平显著升高，其可能通过调节IFN-γ和IL-17等炎性因子水平来影响患者的免疫功能，参与其发病，提示CD200有望成为隐球菌脑病免疫治疗的一个新的靶点。

Objective To analyze the expression of CD200 in peripheral blood for patients with cryptococeal meningitis,and the relationship between it and other inflammatory factor levels. Methods 25 patients with cryptococcal meningitis treating in Changhai Hospital and Changzheng Hospital from June 2009 to November 2013 were enrolled for the study as observation group. 57 healthy adults who received check-up in the same time were randomly selected as control group. Their peripheral blood were collected and separated for peripheral blood mononuelear cell （PBMC）. Reverse transeriptase-polymerase chain reaction （RT-PCR） was used to detect the mRNA level of CD200 in PBMC. Enzyme-linked immunosorbent assay （ELISA） was performed to detect the protein level of CD200, IL-17, TNF-a and IFN-γ in plasma. Pearson correlation analysis was used to investigate the relationship between CD200 and these inflammatory factors. Results The mRNA level of CD200 in PBMC of observation group and control group were 1.73 ± 0.51,1.69 ± 0.47 respectively, and there was no significant difference between them （P〉0.05）. The protein level of CD200 in plasma of observation group was 212.3 ± 70.5 pg/ml, which was significantly higher than 90.5±32.2 pg/ml of control group （P〈0.05）. The levels of TNF-a and IFN-γ in plasma of observation group were significantly lower than that of control group while the level of IL-17 was significantly higher than that of control group （P〈0.05）. Result of Pearson correlation analysis showed that the protein level of CD200 in plasma negatively correlated with level of IFN-γ （r=-0. 635 ,P〈 0. 001） ,and it positively correlated with level of IL -17 （r=0. 668,P〈0. 001）. Conclusion Patients with cryptococcal meningitis had a significant rise in the protein level of CD200 in plasma, which may influence patients＇ immune function and participate its onset by adjusting inflammatory factor levels such as IFN-γ/and IL-17. So CD200 may become a new target of immunotherapy for cryptococcus meningitis.