CD4 and infection: First, to define the kinetics of CD4+ T cell dependency during acute infection in more detail, we transiently depleted CD4+ T cells at selected time points post-infection in C57BL/6 mice (depletion start: day -4, 0, 3, 6, 7, 8, 9, 12, 15, 18 pi) (Fig 1A) and analyzed NrHV viremia over time.