HIV infection is characterized by increased fractions of MIP-1β⁺ and decreased fractions of IL-2⁺ CMV-specific CD4 T cells. (left) The fraction of IFN-γ⁺, TNF⁺, MIP-1β⁺, or IL-2⁺ among total cytokine positive CD4 T cells (y axis) is shown for HIV⁻ (n = 11) and HIV⁺ subjects (n = 16). (right) The fraction of IL-2⁺MIP-1β⁺, IL-2⁺MIP-1β⁻, and IL-2⁻MIP-1β⁺ among total cytokine-positive CD4 T cells. PBMCs were stimulated overnight with whole inactivated CMV and the background (unstimulated control) was subtracted. Statistical analysis was performed using the Mann-Whitney test.