Recurrent human herpes simplex lesions are infiltrated by macrophages and CD4 and CD8 lymphocytes, which secrete cytokines and chemokines. Vesicle fluid was examined by ELISA for the presence of cytokines and β (C-C) chemokines. On the first day of the lesion, high concentrations of interleukin (IL)-1β and IL-6, moderate concentrations of IL-lα and IL-10, and low concentrations of IL-12 and β chemokines were found; levels of macrophage inflammatory protein (MIP)-1β were significantly higher than levels of MIP-1α and RANTES. At day 3, the concentrations of IL-1β, IL-6, and MIP-1β were lower, whereas the levels of IL-10, IL-12, and MIP-1α remained similar, and the level of tumor necrosis factor-α was now detectable. Herpes simplex virus infection of keratinocytes in vitro stimulated production of β chemokines followed by IL-12 and then IL-10, IL-1α, IL-1β, and IL-6, indicating a potential role for these events in early recruitment, activation, and interferon-γ production of CD4 cells in herpetic lesions.