Design of high-specificity binders for peptide-MHC-I complexes

Area of Science:

• Immunology
• Protein Engineering
• Computational Biology

Background:

• Class I major histocompatibility complex (MHC-I) molecules present intracellular peptides for immune surveillance.
• Targeting disease-specific peptide-MHC-I (pMHCI) complexes offers therapeutic potential.
• Achieving specificity requires recognizing disease-associated peptides while avoiding ubiquitous MHC interactions.

Purpose of the Study:

• To design novel pMHCI-binding proteins with high specificity for diseased cells.
• To utilize computational methods for protein design against specific pMHCI targets.
• To validate the therapeutic potential of designed binders in T cell activation.

Main Methods:

• Employed RFdiffusion, a protein design algorithm, to generate pMHCI binders.
• Initiated design processes from experimental or predicted pMHCI structures.
• Incorporated designed binders into chimeric antigen receptors (CARs) for functional testing.

Main Results:

• Successfully identified specific binders for 11 distinct target pMHCI complexes.
• Designs demonstrated extensive contacts with the peptide portion of pMHCI.
• CARs incorporating eight of the designed binders mediated peptide-specific T cell activation.

Conclusions:

• The developed protein design approach enables targeted recognition of disease-associated pMHCI.
• Engineered pMHCI binders show promise for developing novel immunotherapies.
• This strategy has broad applicability for both protein- and cell-based pMHCI targeting.