CD44 and infection: On day 5 post-infection, the vast majority of antigen-specific IFN-γ+ T cells in the ear were derived from the CD44+CD4+T-bet+CD62L− effector population that had not divided, while very few IFN-γ+CD44+CD4+T-bet+CD62L+ T cells were found, and those that were found had undergone proliferation.