OVA Peptides

OVA is a model antigen extensively studied

Proteolytic processing of proteins in the cytoplasm generates peptide epitopes that are generally 8-10 amino acids in length. The binding of these peptides to the surface major histocompatibility complex (MHC) class I molecules and subsequent presentation to T-cells elicits an immune response.¹

A model antigen extensively studied is Ovalbumin (OVA). OVA is processed to the presenting octapeptide (257-264), SIINFEKL, through proteasomal and non-proteasomal activities.² As with peptides naturally presented by H-2Kb, SIINFEKL has on its 5th position an amino acid with an aromatic side chain (Phe) and on the 8th position, an aliphatic side chain (Leu).³ Variants of this peptide consisting of substituting different amino acids at strategic positions have yielded valuable information on the interaction of this peptide and the MHC complex.³

References
1. Heemel, M & H. Ploegh Annu. Rev. Biochem. 64, 463 (1995).
2. Beninga, J. et al. J. Biol. Chem. 273, 18734 (1998).
3. Hin, S. et al. J. Biol. Chem. 276, 48790 (2001).