Immune effects of different forms of vaccines of meningococcus serogroup B outer membrane protein 0315 / 中国免疫学杂志

ABSTRACT

Objective:To evaluate preliminarily immunocompetence and immunoprotection of a NMB0315 nucleic acid vaccine,a recombinant protein vaccine and a nucleic acid vaccine plus a recombinant protein vaccine against Neisseria meningitidis serogroup B in mice, and to provide reliable experimental basis for further exploration of the effective immunization methods and pathways of NMB0315 vaccine. Methods:The NMB0315 nucleic acid vaccine [ pcDNA3. 1 (+)/NMB0315 ] and recombinant protein vaccine(pET-30a/NMB0315)were prepared. Female BALB/c mice were inoculated with a NMB0315 DNA vaccine followed by boosting with recombinant protein NMB0315 through intramuscular and intraperitoneal immunization respectively. Next, humoral immunologic response and cellullar immunologic response were detected in female BALB/c mice by ELISA. The survival rate of BALB/c mice was used to evaluate immunoprotection of the vaccines in mice. Results:Specific IgG,IgG1,IgG2a,and sIgA,induced by the NMB0315 DNA vaccine(pNMB0315-CpG),protein NMB0315 vaccine(rNMB0315-FA),NMB0315 DNA vaccine prime-protein boost at week 8, were detected by indirect ELISA,the A450 values were up to(0. 505±0. 042,0. 513±0. 022,0. 342±0. 017,0. 250±0. 015),(0. 823± 0. 061,0. 807±0. 045,0. 596±0. 027,0. 450±0. 028)and(0. 694±0. 053,0. 711±0. 032,0. 455±0. 021,0. 386±0. 024)respectively, which was significantly higher than the PBS control(P<0. 05). The antibody level of protein vaccine was significantly higher than the nucleic acid vaccine group and combined immunization group ( P<0. 05 ) . The stimulation index and IFN-γ level of combined immunization group were significantly higher than the protein vaccine group and nucleic acid vaccine group(P<0. 05). The bactericidal titer of nucleic acid vaccine group, protein vaccine group and combined immunization group reached 164, 1128 and 1128 respectively,and the protection rates were 70%,95% and 80% respectively. The IgG2a/IgG1 ratios of the nucleic acid vaccine group, the recombinant protein vaccine group and the combined immunization vaccine group were all less than 1 at week 2, 4, 6, 8. Conclusion:The humoral immunity effects( including mucosal immune) induced by the NMB0315 vaccines form high to low were as followsthe recombinant protein vaccine group, the combined immunization vaccine group, the nucleic acid vaccine;and the cellular immune effects from high to low were as followsthe combined immunization vaccine group, the nucleic acid vaccine group, the recombinant protein vaccine group;The protection effects induced by the NMB0315 vaccines in BALB/c mice within 72 hours from high to low were as followsthe recombinant protein vaccine group, the combined immunization vaccine group, the nucleic acid vaccine group.