Salmonella Persistence and Host Immunity Are Dictated by the Anatomical Microenvironment

Abstract

The intracellular bacterial pathogen Salmonella is able to evade the immune system and persist within the host. In some cases, these persistent infections are asymptomatic for long periods and represent a significant public health hazard because the hosts are potential chronic carriers, yet the mechanisms that control persistence are incompletely understood. Using a mouse model of chronic typhoid fever combined with major histocompatibility complex (MHC) class II tetramers to interrogate endogenous, Salmonella -specific CD4 + helper T cells, we show that certain host microenvironments may favorably contribute to a pathogen’s ability to persist in vivo .