CCR7 and HIV-1 infection: However, studies based on other differentiation markers such as CD27 revealed similar findings in that levels of HIV-1 specific T cells exhibiting the CD8+/CD27− effector phenotype, which may largely overlap with the CD45RA+/CCR7− phenotype of the above quoted model, were associated with delayed disease progression in untreated HIV-1 infection [32], [33].