Figure 2.

Phenotypic identification of CD4⁺ T lymphocyte subsets by polychromatic flow cytometry. Representative gating strategies are shown for identification of various subpopulations of CD4⁺ T cells in whole PBMC. (A) First, lymphocytes were gated based on forward-versus-side-scatter characteristics and CD4⁺ αβ T cells were identified as CD4⁺CD3⁺CD8⁻ and negative for the γδ T cell receptor. Secondly, (B) naïve and central memory CD4⁺ T cells were phenotyped as CD28⁺CD95⁻ and CD28⁺CD95⁺, respectively. (C) Frequency of CCR5 expression was quantified on the bulk CD4⁺ T cell population.