A post-translational regulatory map of chronic antigen-driven human T cell dysfunction

Area of Science:

• Immunology
• Molecular Biology
• Cancer Research

Background:

• T cells exposed to persistent antigens, as seen in chronic infections or cancer, exhibit diminished self-renewal and cytotoxic functions.
• While transcriptional, epigenetic, and metabolic factors are known drivers of T cell dysfunction, post-transcriptional regulation remains less understood.

Purpose of the Study:

• To elucidate the post-transcriptional regulatory mechanisms governing T cell dysfunction during chronic antigen exposure.
• To characterize the proteomic landscape of human T cells undergoing antigen-driven dysfunction over time.

Main Methods:

• Time-resolved proteomic analysis of human T cells subjected to persistent T cell receptor stimulation.
• Investigation of changes in canonical exhaustion-associated proteins, mitochondrial function, redox homeostasis, nucleotide metabolism, and cell-cycle progression.
• Validation of identified stress response pathways in vivo and assessment of their impact on T cell cytotoxic capacity.

Main Results:

• Persistent T cell receptor stimulation led to significant proteomic remodeling in T cells.
• Observed alterations included changes in T cell exhaustion markers, mitochondrial proteins, redox homeostasis regulators, nucleotide metabolism enzymes, and cell-cycle proteins.
• Activation of specific stress response pathways in dysfunctional T cells was confirmed in vivo and found to influence cytotoxic function.

Conclusions:

• The study provides a comprehensive proteomic resource detailing post-transcriptional changes in dysfunctional T cells.
• Targeting identified stress response pathways holds potential for enhancing T cell-mediated cancer immunotherapy.
• Novel cysteine-directed therapeutics may be developed to reinvigorate T cell function in cancer patients.