Putative existence of reciprocal dialogue between Tfh and B cells and its impact on infectious and autoimmune disease.

The evolution of the immune system to combat infectious disease is inextricably linked to the concomitant risk of autoimmunity. Central to the immune response in both scenarios is T cell-dependent antibody production. Thus, understanding the fundamentals of this process has important applications in both infectious and autoimmune or inflammatory disease. Recently, considerable attention has been paid to Tfh cells in this process both in terms of how they are generated and what role they play in antibody responses via their transit into the B cell follicle. However, there has been relatively little focus on what this mobilization to the follicle does for the Tfh cell. Thus in this article we review the current literature on Tfh cells in infection, autoimmunity and inflammatory disease and also highlight areas of controversy, with a particular focus on the potential importance of the follicular environment for T cell differentiation and function.