Control of antigen presentation on MHC-I by a bacterial secretion system.

ABSTRACT: Mycobacterium tuberculosis (Mtb) remains one of the world's leading infectious killers. Although CD8 T cells contribute to immune control of tuberculosis, the pathways through which bacterial antigens access major histocompatibility complex class I (MHC-I) antigen presentation remain incompletely defined. Here, we show that the activity of an Mtb secretion system actively promotes antigen presentation on MHC-I. Using quantitative immunopeptidomics, host and bacterial genetic perturbations, and T cell activation assays, we demonstrate that presentation of Mtb-derived peptides on MHC-I requires the ESX-1 type VII secretion system. Presentation of these peptides proceeds in a manner dependent on the transporter associated with antigen processing (TAP) but independent of host cell mecha

SUBMITTER: Leddy O 

PROVIDER: S-EPMC12667757 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature