Polyfunctionality of HIV-specific CD8⁺ T cells is associated with T cell mediated target killing.

<p><i>In vitro</i> cultured human HIV-specific (KK10) CD8⁺ T cell clones were incubated with KK10-loaded target cells (HLA-B*2705⁺ lymphoblastoid cell lines). To measure T cell killing a standard chromium release assay was employed using ⁵¹Cr charged target cells loaded with a serial dilution of KK10-antigen [10^-6M—10^-13M]. Non-⁵¹Cr charged target cells with an identical serial dilution of KK10-antigen were employed to analyse T cell polyfunctionality by multiparametric flow cytometry (CD107a, IFN-γ, TNF-α, IL-2, MIP-1β). <b>A)</b> Scatter plots showing the association between T cell killing (⁵¹Cr release / max ⁵¹Cr release) and T cell polyfunctionality quantified as the polyfunctionality index (<i>q</i> = 1). <b>B)</b> Non-linear regression for all T cell clones identifies the optimal q-value as 1.24.