Cui Na, Su Long-Xiang, Wang Hao, Xiao Meng, Yang Fei, Zheng Min, Li Xin, Xu Ying-Chun, Liu Da-Wei
Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.
Department of Clinical Laboratory, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100730, China.
Chin Med J (Engl). 2016 Jul 20;129(14):1704-10. doi: 10.4103/0366-6999.185858.
Aspergillosis infection is common in the patients with insufficient immunity. The role of mammalian target of rapamycin (mTOR), T-box expressed in T-cells (T-bet), and eomesodermin (EOMES) in mediating T lymphocytes differentiation in response to Aspergillus fumigatus infection in immunocompromised rats was investigated in this study.
Invasive pulmonary aspergillosis (IPA) of immunosuppressive twenty male rats were established and sacrificed at 24 h (n = 5), 48 h (n = 5), 72 h (n = 5), and 96 h (n = 5) after A. fumigatus infection. In addition, control (n = 5), cyclophosphamide (CTX) (n = 5), and aspergillosis (n = 5) group were also established the tissues and pathology of lung tissue was examined by hematoxylin and eosin staining. CD8+ T-cells was sorted by flow cytometry. Serum mTOR, S6K, T-bet, and EOMES were quantified by enzyme-linked immunosorbent assay.
Histology of lung tissue indicated severe lung tissue injury including infiltration of inflammatory cells, alveolar wall damage or degradation, blood congestion, and hemorrhage in the CTX, IPA, and CTX + IPA rats. Hyphae were seen in the IPA, and CTX + IPA groups. The proportion of CD8+ T-cells was significantly increased in the animals of CTX + IPA. Memory CD8+ T-cells was significantly increased in early stage (24 h and 48 h, P < 0.001), but decreased in the late phase of fungal infection (72 h and 96 h) in the animals of CTX + IPA. In addition, at early stage of fungal infection (24 h and 48 h), serum mTOR (P < 0.001), S6K (P < 0.001), and T-bet (P < 0.05) was significantly higher, while EOMES was significantly lower (P < 0.001), in CTX + IPA group than that in control, CTX alone or IPA alone group. Conversely, serum mTOR, S6K, T-bet, and EOMES showed opposite changed in the late stage (72 h and 96 h). Pearson's correlation analysis indicated that mTOR and S6K were significantly correlated with T-bet (r = 0.901 and 0.91, respectively, P < 0.001), but negatively and significantly correlated with EOMES (r = -0.758 and -0.751, respectively, P < 0.001).
mTOR may regulate transcription factors of EOMES and T-bet, and by which mechanism, it may modulate lymphocytes differentiation in animals with immune suppression and fungal infection.
曲霉病感染在免疫力低下的患者中很常见。本研究探讨了雷帕霉素靶蛋白（mTOR）、T细胞表达的T盒蛋白（T-bet）和胚外中胚层决定因子（EOMES）在介导免疫功能低下大鼠对烟曲霉感染的T淋巴细胞分化中的作用。
建立20只雄性免疫抑制大鼠的侵袭性肺曲霉病（IPA）模型，并在烟曲霉感染后24小时（n = 5）、48小时（n = 5）、72小时（n = 5）和96小时（n = 5）处死。此外，还设立了对照组（n = 5）、环磷酰胺（CTX）组（n = 5）和曲霉病组（n = 5），通过苏木精-伊红染色检查肺组织的组织学和病理学。通过流式细胞术分选CD8 + T细胞。采用酶联免疫吸附测定法对血清mTOR、S6K、T-bet和EOMES进行定量分析。
肺组织组织学检查显示，CTX组、IPA组和CTX + IPA组大鼠出现严重的肺组织损伤，包括炎性细胞浸润、肺泡壁损伤或破坏、充血和出血。在IPA组和CTX + IPA组中可见菌丝。CTX + IPA组动物的CD8 + T细胞比例显著增加。CTX + IPA组动物在真菌感染早期（24小时和48小时）记忆CD8 + T细胞显著增加（P < 0.001），但在真菌感染后期（72小时和96小时）减少。此外，在真菌感染早期（24小时和48小时），CTX + IPA组血清mTOR（P < 0.001）、S6K（P < 0.001）和T-bet（P < 0.05）显著升高，而EOMES显著降低（P < 0.001），高于对照组、单独CTX组或单独IPA组。相反，血清mTOR、S6K、T-bet和EOMES在后期（72小时和96小时）呈现相反变化。Pearson相关性分析表明，mTOR和S6K与T-bet显著相关（r分别为0.901和0.91，P < 0.001），但与EOMES呈显著负相关（r分别为-0.758和-0.751，P < 0.001）。
mTOR可能调节EOMES和T-bet的转录因子，通过该机制，它可能调节免疫抑制和真菌感染动物的淋巴细胞分化。
