Rananaware Supriya Rajendra, Pathak Sanmoy, Majumdar Shamik, Joseph Joel P, Ramteke Nikita S, Adiga Vasista, Nandi Dipankar
Department of Biochemistry, Indian Institute of Science, Bangalore, 560012, India.
Centre for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, 560012, India.
Microb Pathog. 2023 Apr;177:106034. doi: 10.1016/j.micpath.2023.106034. Epub 2023 Feb 21.
Typhimurium infection in mice results in drastic loss of immature CD4 CD8 double negative (DN) and CD4 CD8 double positive (DP) thymic subsets compared to mature single positive (SP) subsets. We investigated changes in thymocyte sub-populations post infection with a wild type (WT) virulent strain and ΔrpoS, a virulence-attenuated strain, of Salmonella Typhimurium in C57BL/6 (B6) and Fas-deficient autoimmune-prone lpr mice. The WT strain caused acute thymic atrophy with greater loss of thymocytes in lpr mice compared to B6 mice. Infection with ΔrpoS caused progressive thymic atrophy in B6 and lpr mice. Analysis of thymocyte subsets revealed that immature thymocytes including the DN, immature single positive (ISP), and DP thymocytes underwent extensive loss. SP thymocytes were more resistant to loss in WT-infected B6 mice, whereas WT-infected lpr and ΔrpoS-infected mice exhibited depletion of SP thymocytes. Overall, thymocyte sub-populations exhibited differential susceptibilities depending on bacterial virulence and the host background.
与成熟的单阳性（SP）亚群相比，小鼠感染鼠伤寒沙门氏菌会导致未成熟的CD4 CD8双阴性（DN）和CD4 CD8双阳性（DP）胸腺亚群急剧减少。我们研究了C57BL/6（B6）和Fas缺陷的自身免疫易感lpr小鼠感染野生型（WT）毒力菌株和鼠伤寒沙门氏菌的毒力减弱菌株ΔrpoS后胸腺细胞亚群的变化。与B6小鼠相比，WT菌株导致急性胸腺萎缩，lpr小鼠中的胸腺细胞损失更大。感染ΔrpoS导致B6和lpr小鼠发生进行性胸腺萎缩。胸腺细胞亚群分析显示，包括DN、未成熟单阳性（ISP）和DP胸腺细胞在内的未成熟胸腺细胞大量减少。在WT感染的B6小鼠中，SP胸腺细胞对损失更具抵抗力，而WT感染的lpr小鼠和ΔrpoS感染的小鼠则表现出SP胸腺细胞的耗竭。总体而言，胸腺细胞亚群根据细菌毒力和宿主背景表现出不同的易感性。
