[An anti-tumor research of recombinant phage vaccine expressed xenogenic EGFR].

Abstract

A recombinant phage vaccine expressing EGFR on it's capsid was constructed and used to study the anti-tumor effect. The T7 phage display system was applied to display seven xenogenic (human, chicken) epidermal growth factor receptor extracellular domain fragments. The EGFR fragment was expressed as fused protein with 10B capsid on the surface of T7 phage. The T7-EGFR phage vaccines were injected into C57BL/6J mice, and then Lewis lung cancer cells were inoculated after 4 weeks immunization. The tumor tissue was excised and weighed after 10 days to evaluate the anti-tumor effect of each experimental group. The EGFR expression of the phage vaccine was verified by western-blot analysis. The A431 cells with high expressed EGFR was used to detect the anti-EGFR antibody by flow cytometry analysis. The results showed that the A431 cell can react with the serum obtained from the mice after three-week immunization. The experimental results confirmed that special EGFR antibody could be induced by the T7-EGFR phage vaccine. The T7-EGFR phage vaccine can elicit endogenous special EGFR antibody in mice and is capable of suppressing the tumor proliferation and retarding the growth of Lewis lung cancer. This research can be used to develop an anti-tumor vaccine for the target-therapy of EGFR(+) tumor.