Construction of a Recombinant Phage-vaccine Capable of Reducing the Growth Rate of an Established LL2 Tumor Model.

Over expression of the epidermal growth factor receptor (EGFR) in many human epithelial tumors has been correlated with disease progression and poor prognosis. EGFR-inhibiting immunotherapy has already been introduced in cancer therapy. Peptide displaying phage particles in eukaryotic hosts can behave as antigen carriers, able to activate the innate immune system and to elicit adaptive immunity. Herein, the M13-pAK8-VIII phagemid plasmid was engineered to contain the sequences for an EGFR mimotope along with the L2 extracellular domain of EGFR (EM-L2) which would produce the final peptide-phage vaccine. The prophylactic and therapeutic effects of this novel vaccine were evaluated on the Lewis lung carcinoma induced mouse (C57/BL6) model. The recombinant peptide was confirmed to be displayed on the surface of M13 phage as an extension for phage's PVIII protein. Immunization of mice with peptide-phage vaccine resulted in antibody production against EM-L2 and significant reduction of tumor growth rate by nearly 25 percent. In conclusion, EM-L2 displaying phage particles could be deemed as an encouraging strategy in contemporary cancer immunotherapy.