Fig. 14.

Structure of Vi polysaccharide (20) and overview of its mechanism of immunosuppression during typhoid infection and in multiple sclerosis. a Salmonella activates the kinase ERK, small Rho family GTPases, Cdc42, and Rac-1 to induce inflammation. Vi released by Salmonella interacts with PHBs to block the activation of ERK, Cdc42 and Rac-1 resulting in reduced invasion of cells with Salmonella and inhibition of inflammatory responses. b Mechanism of immunosuppression of Vi (20) and rocaglamide (1) in T helper 17 cells in multiple sclerosis