The role of T cell immunity in HIV-1 infection

•Responses to structurally constrained regions of HIV-1 are most effective in reducing viral replication.•The quality of the T cell response is important; polyfunctionality, balance of Treg vs Th17 and infection of TFH.•T cell responses in studies of controllers and progressors are instructive for future development of therapies and vaccines.

The interplay between the T cell immune response and human immunodeficiency virus (HIV)-1 largely determines the outcome of infection. Typically, the virus overcomes the immune defences leading to a gradual decline in function that permits the development of disease. In recent years, a concerted effort in comparing T cell responses between 'controllers' and 'progressors' is beginning to identify the T cell subsets and factors that affect disease progression related to the effector functions of both CD4 and CD8 T cells. These efforts are providing opportunities for development of novel therapies and vaccines.