Expression and purification of a novel multi-epitope peptide vaccine for breast cancer immunotherapy

Abstract

BACKGROUND. The most cause of cancer-related death in women population is breast cancer (BC). Hence, efforts to develop an effective treatment against BC are needed. Since the large proportion of BC is due to over-expression of tumor-associated antigens (TAAs), multi-epitope cancer vaccines are considered as a promising therapeutic approach. The aim of the current study is the production of the novel multi-epitope peptide vaccine against BC in a prokaryotic host. Our novel multi-epitope BC vaccine consists of four sections: 1) cytotoxic T lymphocytes epitopes from human epidermal growth factor receptor, heparanase, mucin 1 protein; 2) helper T lymphocytes epitopes from survivin; 3) a segment of Por B protein a immunostimulatory adjuvant, which was selected from Neisseria meningitides by bioinformatics analysis; 4) a segment of murine ULBP-like transcript 1, which binds to a natural killer group 2 member D receptor in tumor microenvironment with high affinity and stimulates innate immune response. All mentioned segments were fused together by proper peptide linkers. METHODS. The designed protein vaccine was expressed in E. coli after induction by isopropyl beta-D-1-thiogalactopyranoside for 4 and 6 h, then the expression of peptide vaccine was analyzed by sodium dodecyl sulphate - polyacrylamide gel electrophoresis and Western blot; moreover, the recombinant vaccine was purified by Ni-NTA spin column in a denatured form. RESULTS. According to our results the multi-epitope peptide vaccine was successfully produced in E. coli host. CONCLUSIONS. The purified vaccine seems to be a promising candidate for BC immunotherapy.