Differential susceptibility and maturation of thymocyte subsets during Salmonella Typhimurium infection: insights on the roles of glucocorticoids and Interferon-gamma

• DOI: 10.1038/srep40793
• Publication Date: 2017-01-16T12:23:29Z
• Authors: Shamik Majumdar; Mukta Deobagkar-Lele; Vasista Adiga; Abinaya Raghavan; Nitin Wadhwa; Syed Moiz Ahmed; Supriya Rajendra ...; Subhashish Chakra...; Omana Joy; Dipankar Nandi
• Keywords: Thymocyte; Double negative; CD5; Salmonella infection

Abstract The thymus is known to atrophy during infections; however, a systematic study of changes in thymocyte subpopulations has not been performed. This aspect was investigated, using multi-color flow cytometry, oral infection mice with Salmonella Typhimurium ( S . Typhimurium). major highlights are: First, block the developmental pathway CD4 − CD8 double negative (DN) thymocytes observed. Second, + positive (DP) thymocytes, mainly DP1 (CD5 lo CD3 ) and DP2 hi int ), but DP3 subsets are reduced. Third, single (SP) more resistant depletion their maturation delayed, leading accumulation CD24 SP. Kinetic studies demonstrated differences sensitivity thymic subpopulations: Immature (ISP) > DP1, DN3, DN4 DN2 Upon infection, glucocorticoids (GC), inflammatory cytokines, e.g. Ifnγ, etc induced, which enhance death. Treatment RU486, GC receptor antagonist, increases survival most infection. Studies Ifnγ −/− that endogenous produced enhances DN2-DN4 subsets, promotes delays SP thymocytes. implications these observations on host cellular responses infections discussed.