CD4 and HIV infectious disease: Some of the genes that help define quiescent CD4+ T cells in cluster 7 have also been reported to be expressed in latent cells, such as HLA-DR (Cohn et al., 2018; Horsburgh et al., 2020; Lee et al., 2017), or, like CD2 or LYAR, upregulated in in vitro models of HIV infection and latency (DeBoer et al., 2014; Iglesias-Ussel et al., 2013).