Nucleobase adducts bind MR1 and stimulate MR1-restricted T cells

Area of Science:

• Immunology
• Cellular Metabolism
• Biochemistry

Background:

• MR1T cells recognize antigens via the MR1 molecule, independent of microbial infection.
• The specific self-antigens triggering MR1T cells and their physiological roles are largely unknown.
• Understanding MR1T cell activation is crucial for exploring their therapeutic potential.

Purpose of the Study:

• To identify the self-antigens that stimulate MR1T cells.
• To elucidate the mechanisms underlying MR1T cell activation.
• To explore the physiological and therapeutic relevance of MR1T cell recognition.

Main Methods:

• Utilized a combination of genetic, pharmacological, and biochemical techniques.
• Investigated the role of carbonyl stress and nucleobase metabolism in MR1T cell activation.
• Analyzed compounds within MR1 molecules produced by tumor cells.

Main Results:

• MR1T cell activation is promoted by carbonyl stress and altered nucleobase metabolism.
• Carbonyl adducts of nucleobases were identified as the stimulatory compounds.
• These adducts were detected within MR1 molecules, particularly in tumor cells.
• Drug-induced carbonyl accumulation enhanced the abundance and antigenicity of these adducts.

Conclusions:

• Carbonyl-nucleobase adducts are identified as the antigens recognized by MR1T cells.
• MR1T cells function as sensors of cellular metabolic changes and carbonyl stress.
• This discovery has implications for understanding immune surveillance and developing novel cancer therapies.