Salmonella typhimurium impedes innate immunity with a mast-cell-suppressing protein tyrosine phosphatase, SptP.

ABSTRACT: The virulence of Salmonella is linked to its invasive capacity and suppression of adaptive immunity. This does not explain, however, the rapid dissemination of the pathogen after it breaches the gut. In our study, S. Typhimurium suppressed degranulation of local mast cells (MCs), resulting in limited neutrophil recruitment and restricting outflow of vascular contents into infection sites, thus facilitating bacterial spread. MC suppression was mediated by secreted effector protein (SptP), which shares structural homology with Yersinia YopH. SptP functioned by dephosphorylating the vesicle fusion protein N-ethylmalemide-sensitive factor and by blocking phosphorylation of Syk. Without SptP, orally challenged S. Typhimurium failed to suppress MC degranulation and exhibited limited colonization

SUBMITTER: Choi HW 

PROVIDER: S-EPMC4326046 | biostudies-literature | 2013 Dec

REPOSITORIES: biostudies-literature