Injection of T3SS effectors not resulting in invasion is the main targeting mechanism of Shigella toward human lymphocytes.

ABSTRACT: The enteroinvasive bacterium Shigella is a facultative intracellular bacterium known, in vitro, to invade a large diversity of cells through the delivery of virulence effectors into the cell cytoplasm via a type III secretion system (T3SS). Here, we provide evidence that the injection of T3SS effectors does not necessarily result in cell invasion. Indeed, we demonstrate through optimization of a T3SS injection reporter that effector injection without subsequent cell invasion, termed the injection-only mechanism, is the main strategy used by Shigella to target human immune cells. We show that in vitro-activated human peripheral blood B, CD4⁺ T, and CD8⁺ T lymphocytes as well as switched memory B cells are mostly targeted by the injection-only mechanism. B

SUBMITTER: Pinaud L 

PROVIDER: S-EPMC5604021 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature