CD4 and infection: Results from PBMCs from 12 different healthy donors infected with VZV Ellen showed that monocytes were the most permissive to VZV infection (mean: 70%, range: 35–97%) followed by NK cells (mean: 32%, range: 12–61%), NKT cells (mean: 19%, range: 12–32%), B cells (mean: 16%, range: 7–29%), CD4+ T cells (mean: 14%, range: 5–29%) and CD8+ T cells were the least permissive to infection (mean: 10%, range: 4–17%) (Fig 1B and S1 Table).