Analysis of the degradation mechanisms of MHC class I-presented tumor antigenic peptides by high performance liquid chromatography/electrospray ionization mass spectrometry: application to the design of peptidase-resistant analogs.
Peptide vaccines based on the use of MHC class I restricted epitopes are currently assayed for anti-tumor and anti-viral immunotherapy. With the aim of designing minimally modified, peptidase-resistant analogs, we developed a rational approach based on a detailed understanding of the degradation mechanism of peptides in serum. Degradation of murine tumor antigen P198 and human tumor antigen MAGE-3.A1 was followed by on line high performance liquid chromatography/electrospray ionization mass spectrometry (HPLC/ESI-MS). This method provided high precision and sensitivity for rapid and direct analysis of degradation fragments in a complex mixture and, very importantly, precise identification of transient degradation fragments present at low concentrations. The design of structurally modified analogs, and the analysis of their degradation by on-line HPLC/ESI-MS, allowed us to to demonstrate the efficiency of local modifications in the protection of a given peptide bond towards a specific peptidase activity.
Ayyoub
M
M
Institut de Pharmacologie et Biologie Structurale, UPR 9062 CNRS, Toulouse, France.
Monsarrat
B
B
Mazarguil
H
H
Gairin
J E
JE
D002851:Chromatography, High Pressure Liquid; D000939:Epitopes; D005805:Genes, MHC Class I / Q000276:immunology*; D006801:Humans; D013058:Mass Spectrometry; D010447:Peptide Hydrolases / Q000378:metabolism*; D010455:Peptides / Q000032:analysis / Q000378:metabolism*; D013056:Spectrophotometry, Ultraviolet
D000939:Epitopes; D010455:Peptides; D010447:Peptide Hydrolases