Streptococcus suis Serotype 2 Infection Causes Host Immunomodulation through Induction of Thymic Atrophy

文献类型: 外文期刊

第一作者: Wang, Shujie

作者: Wang, Shujie;Lyu, Chuang;Meng, Fandan;Yang, Yong-Bo;He, Xijun;Cai, Xuehui;Wang, Gang;Li, Ganwu;Duan, Guixin;Gottschalk, Marcelo;Gottschalk, Marcelo;Yu, Ying;Wang, Zhenzhong

作者机构:

关键词: immunomodulation; infection; Streptococcus suis; thymic atrophy

期刊名称:INFECTION AND IMMUNITY ( 影响因子:3.441; 五年影响因子:3.702 )

ISSN: 0019-9567

年卷期: 2020 年 88 卷 4 期

页码:

收录情况: SCI

摘要: Streptococcus suis serotype 2 is an important bacterial pathogen of swine and is also an emerging zoonotic agent that may be harmful to human health. Although the virulence genes of S. suis have been extensively studied, the mechanisms by which they damage the central immune organs have rarely been studied. In the current work, we wanted to uncover more details about the impact and mechanisms of S. suis on specific populations of thymic and immune cells in infected mice. Terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) assays revealed that S. suis infection induced apoptosis in CD3(+), CD14(+), and epithelial cells from the thymus. S. suis infection resulted in a rapid depletion of mitochondrial permeability and release of cytochrome c (CytC) and apoptosis-inducing factor (AIF) through upregulation of Bax expression and downregulation of Bcl-xl and Bcl2 expression in thymocytes. Moreover, S. suis infection increased cleavage of caspase-3, caspase-8, and caspase-9. Thus, S. suis induced thymocyte apoptosis through a p53- and caspase-dependent pathway, which led to a decrease of CD3(+) cells in the thymus, subsequently decreasing the numbers of CD4(+) and CD8(+) cells in the peripheral blood. Finally, expression dysregulation of proinflammatory cytokines in the serum, including interleukin 2 (IL-2), IL-6, IL-12 (p70), tumor necrosis factor (TNF), and IL-10, was observed in mice after S. suis type 2 infection. Taken together, these results suggest that S. suis infection can cause atrophy of the thymus and induce apoptosis of thymocytes in mice, thus likely suppressing host immunity.

分类号:

  • 相关文献
作者其他论文 更多>>