Unlike the poorly proliferating CD27− CD45RA+ T cells as well as CD27− CD45RA− T cells in latent CMV infection [53], [54], the CD27− CD45RA− subsets in LTBI display robust proliferative capacity in vitro in response to stimulation with CW antigens (T.A. and J.R., unpublished data). Here, CD27 is linked to cytomegalovirus infection.