CD4 and cervicitis: In this study, we have used CD4- and CD8-depleted populations of responder cells in an ELISPOT assay of IFN-γ release to screen directly ex vivo for both CD4+ and CD8+ T-cell responses to five HPV16 proteins (E6, E7, E4, L1 and L2) from a cohort of 41 women with varying grades of cervical disease.