By infecting mice with different viral and bacterial vectors loaded with a fixed epitope, Rudd et al. (33) investigated the influence of the infectious/inflammatory context on the TCR diversity of the CD8+ T cell response and show that although the type of infection in which the epitope was encountered can influence the magnitude of the CD8+ T cell responses, TCR β-chain repertoires did not significantly differ among the different infection models. The gene discussed is CD8A; the disease is infection.