CCR7 and infection: The number of naïve CD4+CD45RO–CCR7+ T cells was strongly decreased in P1 and P2 compared to their mother and a HD control, whereas the frequencies of CD4+CD45RO+CCR7– effector memory T cells were increased (S.K., S.F. unpublished observations), which was most likely a consequence of the patients’ chronic and recurrent infections (McCarl et al, 2009; Lian et al, 2018).