Dectin-1和TLR2/TLR3/TLR4受体在免疫缺陷小鼠侵袭性肺曲霉菌病的表达  

Dectin-1 and TLR2/TLR3/TLR4 receptors expression of invasive pulmonary aspergillosis in immunosuppressed mice

作　　者：栗方[1] 曹彬[1] 曲久鑫[1] 沈鸿[1] 刘振嘉[1] 王鹏[1] 

机构地区：[1]首都医科大学附属北京朝阳医院感染和临床微生物科,100020

出　　处：《中华临床医师杂志（电子版）》2015年第9期116-120,共5页Chinese Journal of Clinicians(Electronic Edition)

基　　金：CHINA_ANTIF_2010辉瑞中国抗真菌科研基金(WS931592);2010杨森科学研究委员会中国分会研究基金

摘　　要：目的本研究利用小鼠动物模型,探讨烟曲霉感染免疫缺陷小鼠TLR2/TLR3/TLR4对树突状细胞植物血凝素-1(Dectin-1)表达的影响。通过检测TLRs和CLRs受体在不同免疫状态下的表达,揭示介导侵袭性肺曲霉菌病(IPA)肺损伤的关键受体。方法小鼠随机分成四组,A组为正常对照组;B组为环磷酰胺免疫抑制+未接种烟曲霉菌;C组正常状态小鼠+烟曲霉菌接种;D组为IPA感染组,免疫抑制+烟曲霉菌接种。采用real-time PCR方法进行小鼠肺组织各个时相点的TLR2、TLR3、TLR4、Dectin-1和β-actin m RNA的表达,检测受体间的相互表达调控。结果正常状态感染组(C组N+AF),TLR4/TLR2、Dectin-1 m RNA比正常对照组表达上调;IPA模型组(D组CP+AF),Dectin-1和TLR4、TLR2 m RNA比正常状态感染组表达下调;但TLR3 m RNA 48 h、72 h表达没有明显不同(P>0.05)。病理切片模型组小鼠72 h可见较严重的出血和充血;96 h时肺内有菌丝,肺泡间隔增宽,支气管壁破坏。正常状态感染烟曲霉小鼠72 h可见充血,肺泡弹性纤维破坏。结论成功建立了小鼠IPA动物模型,Dectin-1受体表达下调可能是环磷酰胺免疫抑制引起IPA的机制之一。Dectin-1的表达可能是建立在TLR2/TLR4对烟曲霉早期识别的基础上,TLR3可能起协同作用。Objective The purpose of the study is using mice animal models to explore the impact of TLR2/TLR3/TLR4 of immunosuppressed mice infected with A. fumigatus on dendritic cells phytohemagglutinin-1 （Dectin-1） expression. By detecting TLRs and CLRs receptors in different immune status expression, we reveal the key receptors-mediated lung injury IPA. Methods The mice were divided into four groups including the group of normal mice, the group of immunosuppressed mice without A. fumigatus injection, the group of normal mice with A. fumigatus injection and the group of IPA mice. The lung tissues from each group were collected for pathological analysis and detecting the expression level of TLR2, TLR3, TLR4, Dectin-1 and β-actin mRNA by real-time PCR, and detecting receptors expression and mutual regulation. Results In the immunocompetent mice infected with A. fumigatus, TLR4/TLR2 and Dectin-1 mRNA expression increased markedly compared with the normal control group. In the immunosuppressed mice infected with A. fumigatus, TLR4/TLR2 and Dectin-1 mRNA expression were inhibited markedly compared with normal mice infected with A. fumigatus, but TLR3 mRNA expression of mice injected after 48 h and 72 h did not show significant difference （P〉0. 05）. IPA mice infected after 72 h showed severe bleeding and congestive, and lung tissue granuloma formation;the 96 h group, showed hyphae,widened alveolar septum, tracheal epithelium cell loss, tissue necrosis. Normal mice infected by Aspergillus fumigatus after 72 h showed visible congestion and destroyed alveolar elastic fibers. Conclusion An experimental animal model of invasive pulmonary aspergillosis was established successfully. Inhibition of Dectin-1 expression may be one of the mechanisms of cyclophosphamide in the development of IPA. Dectin-1 expression may be established in the early stage of TLR2/TLR4 identification of the A. fumigatus, whereas TLR3 may play a synergistic role.

关 键 词：小鼠 近交BALBC 烟曲霉菌 免疫抑制 侵袭性肺曲霉菌病 

分 类 号：R519[医药卫生—内科学]