In untreated subjects with chronic HIV-1 infection and active HIV replication (i.e. detectable viral loads), percentages of Tim-3+ bulk (p = 0.006, Spearman r = 0.46) and CD56dim (p = 0.004, Spearman r = 0.48) NK cells were even more strongly associated with CD4+ T-cell counts. Here, CD4 is linked to HIV-1 infection.