CD8 T cells cross-restricted by HLA-B*57 and HLA-E*01 recognize HIV Gag with different functional profiles [dataset 2]

Few non-classical HLA-E restricted HIV-specific epitopes have been described, and even less is known about the functional profile of responding CD8 T cells (CD8s). This study evaluates the functional characteristics of CD8s targeting the Gag epitope (KAFSPEVIPMF or KF11) based on their restriction by either HLA-E (E-CD8s) or HLA-B57 (B57-CD8s). CD8s from 8 people with HIV (PWH) were cocultured with KF11 peptide presented by cell lines expressing HLA-B*57:01, HLA-E*01:01 or E*01:03. CD8s were analyzed through single-cell (sc) RNA and TCR sequencing. Additionally, supernatants were analyzed for soluble proteomics using a Luminex assay. B57-CD8s secreted higher levels of cytotoxic cytokines such as IFNγ, while E-CD8s produced more chemotactic cytokines, including RANTES, CXCL10 (IP-10), and IL27confirmed through scRNAseq. Despite distinct cytokine profiles, TCR clonotypes stimulated by KF11 were cross-restricted by HLA-B*57 and HLA-E*01/03. In vitro T cell reporter assays clearly demonstrated this cross-restriction. A TRAV5-containing metaclonotype cluster was seen in PWH with lower viral loads. These findings demonstrate that HIV-specific CD8s in PWH exhibit cross HLA-B*57 and HLA-E*01/03 restriction, resulting in functionally distinct immune responses that may contribute to HIV control.