Major histocompatibility complex class I presenting ovalbumin-derived peptide SIINFEKL (H-2Kb/SIINFEKL)

The Major Histocompatibility Complex (MHC) class I molecule presenting the ovalbumin-derived peptide SIINFEKL (residues 257–264) is a fundamental model system in immunology (Rock et al., 1990). In C57BL/6 mice, the SIINFEKL peptide is processed from the chicken egg white protein ovalbumin and presented on the cell surface by the H-2Kb MHC class I allele. This specific peptide-MHC (pMHC) complex is the primary ligand for the OT-I T-cell receptor, making it an essential tool for studying CD8+ T-cell activation, proliferation, and effector function (Hogquist et al., 1994). Although ovalbumin is not a human pathogen or tumor antigen, this system is widely used in preclinical research to simulate tumor-associated antigens and evaluate the efficacy of vaccines and immunotherapies. Experimental drugs targeting this complex include TCR-like antibodies, such as 25-D1.1, and engineered T-cell therapies that recognize the pMHC with high specificity (Porgador et al., 1997). The complex is also used to investigate antigen cross-presentation and the mechanisms of immune tolerance and exhaustion in various disease models.

Other names

H-2Kb-SIINFEKL complexOVA(257-264)/H-2KbMHC-I/SIINFEKLOvalbumin peptide-MHC complexpMHC-SIINFEKL

The complex acts as a specific ligand for the T-cell receptor (TCR) on CD8+ T cells, initiating the formation of the immunological synapse and subsequent cytotoxic activity (Hogquist et al., 1994; Rock et al., 1990).