Figure 6.

CD8⁺ T cell functional avidity and control of viral replication. (A) Representative example of peptide titrations in IFN-γ ELISPOT assays (normalized SFC per 10⁶ PBMCs) to assess functional avidity of KK10 or other HIV epitope–specific CD8⁺ T cells. Functional avidity is defined as the concentration required to achieve half-maximal recognition of the wild-type peptide (EC₅₀). Error bar values are 95% confidence intervals. (B) Functional avidity of CD8⁺ T cell populations specific for HLA-A–restricted (including 2, 3, 11, 26, and 31) or HLA-B–restricted (including 7, 8, 27, 35, and 51) HIV epitopes (n = 20), as well as for B27-KK10. Horizontal bars represent means. p-values were calculated by the Mann-Whitney U test. (C) Correlation between functional avidity of immunodominant HIV-specific CD8⁺ T cell responses and HIV cVL. Immunodominant (n = 16, closed symbols) and the highest subdominant (n = 12, open symbols) responses are shown, as is a linear regression trend line. p-values and r values between cVL, pVL, CD4 count, and functional avidity are shown for the immunodominant responses. Spearman's rank test was used to determine correlations.