[The antiangiogenic effect of DNA vaccine based on beta-defensin 2 fused with VE-cadherin].

OBJECTIVE: To explore the feasibility of generating beta defensin 2 fusion vaccine to break the immune tolerance of self antigens associated with angiogenesis. METHODS: PCR amplification of mature beta defensin 2 (Def) and extracelluar segment of Vascular Endothelial Cadherin (Cad) was conducted. (GGGS)3 was used as linker peptide for fusion plasmid(Def-Cad). All the three segments were inserted into pSecTag2B plasmid (pSec), and CT26 tumor cells were transfected. Expression was verified by RT-PCR and chemotaxis assay. The alginate bead model was used to study the antiangiogenic effect of fusion plasmid vaccination. RESULTS: All constructions were verified by sequencing and were found expressed in mammalian cell. The beta defensin 2 fusion protein had similar capacity to chemoattract dendritic cells as compared with nonfusion protein (P>0.05). The alginate bead assay revealed that the tumor-induced angiogenesis in fusion plasmid immunized mice was significantly suppressed when compared with that in nonfusion plasmid (P<0.01). CONCLUSION: An active immunization strategy based on beta defensin 2 fused with angiogenesis related antigen of endothelial can inhibit angiogenesis and may be a useful approach for cancer therapy.