免疫抑制剂对小鼠肺泡巨噬细胞抗曲霉感染相关受体mRNA表达的影响

Effects of immunosuppressive agent on mRNA expression of anti-aspergillus infection-associated receptors on alveolar macrophage

目的探讨免疫抑制剂对小鼠肺泡巨噬细胞抗曲霉感染相关受体mRNA表达的影响。方法30只昆明小鼠随机分为2组：正常对照组（6只）和免疫抑制组（24只，环磷酰胺150mg／kg腹腔注射）。免疫抑制组小鼠注射环磷酰胺后4h、8h、16h及24h，分别随机取6只进行支气管肺泡灌洗，收集肺泡巨噬细胞。正常对照组小鼠注射生理盐水24h后处死，收集肺泡巨噬细胞。使用逆转录-聚合酶链反应检测小鼠肺泡巨噬细胞Toll样受体2（TLR2）、TLR4、树突状细胞相关C型凝集索1（Dectine-1）mRNA表达变化。结果与正常对照组比较，腹腔注射环磷酰胺4h后，TLR2mRNA表达即出现显著下降（P〈0．01）；在腹腔注射环磷酰胺8h后TLR4mRNA表达出现显著下降（P〈0．01）；Dectine-1 mRNA在腹腔注射环磷酰胺后无明显变化。结论免疫抑制剂环磷酰胺能够下调肺泡巨噬细胞抗曲霉感染相关受体TRL2和TLR4mRNA的表达，对Dectine-1mRNA的表达未见明显影响。

Objective To investigate the effects of immunosuppressive agent on mRNA expression of anti-aspergillus infection-associated receptors on alveolar macrophage. Methods Thirty Kunming mice were randomly divided into two groups：normal control group （ n = 6） and immunocompromise group （150 mg/kg eyclophosphamide,intraperitoneal injection, n = 24）. Six mice were randomly taken to collect alveolar macrophage by bronchoalveolar lavage from immunocompromise group at time of 4,8,12 and 24 hours after immunosuppression. Mice in normal control group were sacrificed to collect alveolar macrophage after receiving normal saline intraperitoneat injection. Reverse transcription-polymerase chain reaction was used for determining the mRNA expression of Toll like receptor 2（TLR2） ,TLR4 and dendritic cell-associated C-type lectin 1 （Dectine-1）. Results TLR2 mRNA expression decreased signifficantly four hours after cyclophosphamide intraperitoneal injection, and decreased continually to 24 hours （all P〈0.0l）. The decrease of TLR4 mRNA expression appeared eight hours after immunosuppression, and decreased continually to 24 hours （all P〈0.01）. There was not significant difference on Dectine-1 mRNA expression between normal control group and immunocompromise group. Conclusions The results suggest that cyclophosphamide could down-regulate the mRNA expression of TLR2 and TLR4 on alveolar macrophage.