Contribution of proteasome-catalyzed peptide cis-splicing to viral targeting by CD8+ T cells in HIV-1 infection

ABSTRACT: Peptides generated by proteasome-catalyzed splicing of non-contiguous amino acid sequences have been shown to constitute a source of non-templated human leukocyte antigen class I (HLA-I) epitopes, but their role in pathogen-specific immunity remains unknown. CD8+ T cells are key mediators of human immunodeficiency virus type 1 (HIV-1) control, and identification of novel epitopes to enhance targeting of infected cells is a priority for prophylactic and therapeutic strategies. To explore the contribution of proteasome-catalyzed peptide splicing (PCPS) to HIV-1 epitope generation, we developed a broadly-applicable mass spectrometry-based discovery workflow that we employed to identify spliced HLA-I-bound peptides on HIV-infected cells. We demonstrate that HIV-1-derived spliced peptides comprise a novel, but relatively minor, component of the HLA-I-bound viral immunopeptidome. Although spliced HIV-1 peptides may elicit CD8+ T cell responses relatively infrequently during infection, CD8+ T cells primed by partially-overlapping contiguous epitopes in HIV-infected individuals were able to cross-recognize spliced viral peptides, suggesting a potential role for PCPS in restricting HIV-1 escape pathways. Vaccine-mediated priming of responses to spliced HIV-1 epitopes could thus provide a novel means of exploiting epitope targets typically under-utilized during natural infection.

INSTRUMENT(S): Orbitrap Fusion Lumos

ORGANISM(S): Homo Sapiens (human) Hiv-1 Vector Pnl4-3

TISSUE(S): Cell Suspension Culture, T Cell, Leukocyte, Cell Culture

DISEASE(S): Acquired Immunodeficiency Syndrome

SUBMITTER: Nicola Ternette  

LAB HEAD: Nicola Ternette

PROVIDER: PXD015489 | Pride | 2019-11-25

REPOSITORIES: Pride