CD4 and infection: Previous studies reporting lower frequencies of M. tuberculosis-specific CD4 T cells and lower cytokine responses to M. tuberculosis and C. albicans but not cytomegalovirus (CMV) in people with HIV56,57, along with preferential HIV in vitro infection of C. albicans- but not CMV-specific CD4 T cells of HIV-uninfected participants58 have suggested that HIV contributes to a vulnerable adaptive immunity to some pathogens due to a loss of antigen-specific CD4 T cells.