Department of Respiratory Medicine, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8575, Japan.
Infect Immun. 2010 May;78(5):2302-11. doi: 10.1128/IAI.01398-09. Epub 2010 Mar 15.
Candida species are the most common source of nosocomial invasive fungal infections. Previous studies have indicated that T-helper immune response is the critical host factor for susceptibility to Candida infection. The transcription factor GATA-3 is known as the master regulator for T-helper type 2 (Th2) differentiation. We therefore investigated the role of GATA-3 in the host defense against systemic Candida infection using GATA-3-overexpressing transgenic mice. The survival of GATA-3-overexpressing mice after Candida infection was significantly lower than that of wild-type mice. Candida outgrowth was significantly increased in the kidneys of GATA-3-overexpressing mice, compared with wild-type mice. The levels of various Th2 cytokines, including interleukin-4 (IL-4), IL-5, and IL-13, were significantly higher while the level of Th1 cytokine gamma interferon was significantly lower in the splenocytes of GATA-3-overexpressing mice after Candida infection. Recruitment of macrophages into the peritoneal cavity in response to Candida infection and their phagocytic activity were significantly lower in GATA-3-overexpressing mice than in wild-type mice. Exogenous administration of gamma interferon to GATA-3-overexpressing mice significantly reduced Candida outgrowth in the kidney and thus increased the survival rate. Administration of gamma interferon also increased the recruitment of macrophages into the peritoneal cavity in response to Candida infection. These results indicate that overexpression of GATA-3 modulates macrophage antifungal activity and thus enhances the susceptibility to systemic Candida infection, possibly by reducing the production of gamma interferon in response to Candida infection.
念珠菌属是医院获得性侵袭性真菌感染最常见的病原体。既往研究表明,辅助性 T 细胞免疫应答是宿主易感性念珠菌感染的关键因素。转录因子 GATA-3 被认为是辅助性 T 细胞 2 型(Th2)分化的主要调节因子。因此,我们使用 GATA-3 过表达转基因小鼠研究了 GATA-3 在宿主防御系统性念珠菌感染中的作用。与野生型小鼠相比,GATA-3 过表达小鼠在念珠菌感染后的存活率明显降低。与野生型小鼠相比,GATA-3 过表达小鼠肾脏中的念珠菌生长明显增加。GATA-3 过表达小鼠在念珠菌感染后,脾细胞中各种 Th2 细胞因子(包括白细胞介素 4 [IL-4]、IL-5 和 IL-13)的水平显著升高,而 Th1 细胞因子 γ干扰素的水平显著降低。与野生型小鼠相比,GATA-3 过表达小鼠对念珠菌感染的腹腔巨噬细胞募集和吞噬活性明显降低。向 GATA-3 过表达小鼠外源性给予 γ干扰素可显著减少肾脏中的念珠菌生长,从而提高存活率。γ干扰素的给药还增加了对念珠菌感染的腹腔巨噬细胞募集。这些结果表明,GATA-3 的过表达调节了巨噬细胞的抗真菌活性,从而增强了对系统性念珠菌感染的易感性,可能是通过减少对念珠菌感染的 γ干扰素产生。