Validation of particulate TLR agonists as vaccine adjuvants for immunization efficiency of M5BT, multi-epitope subunit vaccine

Abstract

Multi-epitope vaccine is one of the strategies to cope with Foot-and-mouth disease which has significant global impact. However, low immunogenicity derived from its protein structure requires aids of adjuvant. CpG ODN and poly I:C are agonists recognized by certain toll-like receptor expressed on immune cells and thereby, modulate innate and adaptive immunity. In this study, first, modified medium was suggested for vaccine production. It was confirmed E.coli cultured in modified terrific broth-2 (T2B) showed improved cell and protein yield. Next, the synergistic adjuvant effect of CpG ODN and poly I:C was evaluated by cell viability, cytokine release and antigen-specific T and B cell immune response through particle formation between vaccine and adjuvant via ionic interaction. Consequently, the adjuvanticity of two TLR agonists had positive effects on cell proliferation, pro-and anti-inflammatory cytokine increase and elicited desirable T and B cell immunity. Therefore, this study was suggested as advanced subunit vaccine strategy combined with efficient culture system and adjuvant partner against FMD infection.