Peptides containing multiple T cell epitopes in Carcinoembryonic Antigen

Abstract

The present study involves the identification of potential peptides containing multiple epitopes from a tumor antigen named carcinoembryonic antigen (CEA). This protein has been reported to be existing as raised levels in different tumor patients while in normal adults its existence is negligible. An immunoinformatic drive was performed to recognize the possible epitopes. Six immunoinformatic softwares were utilized to predict CD4+ (HLA class I) and CD8+ (HLA class II) T cell epitopes. Finally five peptide fragments from the protein were obtained that comprised of overlapping T cell epitopes of both the HLA molecules. Population coverage of these peptides was analysed to show their potential to elicit an immune response by a wide population of the world and the result indicates that these peptides are expected to response in wide populations. The binding affinity of the peptides with the HLA class I and II alleles were evaluated through peptide docking tool. Molecular docking results show that the binding affinity of these peptides with different HLA molecules is within the range of natural peptides. One peptide fragment was synthesized and analysed for its immunogenic property through PBMC proliferation assay invitro. Thus the study contributes a few peptide targets in CEA which may be considered as candidates for cancer vaccine design.