Effect of intranasal immunization with soluble tachyzoites antigen in combination with propolis and IFN-γ on antibody levels in mice

Objective To observe the dynamic changes of IgG in sera as well as IgA in fecal,nasal and vaginal washing in mice intranasaly immunized with soluble tachyzoites antigen(STAg) in combination with propolis and gamma interferon(IFN-γ) and to explore the mechanism of the vaccine against infection with Toxoplasma gondii.Methods Ninety-six female BALB/c mice were randomly divided into immunized and control groups and immunized with 2 doses of STAg plus propolis and IFN-γ against Toxoplasma gondii and phosphate buffer solution,respectively,at an interval of 2 weeks.The mice were killed on 1st,2nd,3rd,4th,6th,8th,10th,and 12nd week after the 2nd dose immunization,respectively,and the levels of IgG in sera as well as IgA in fecal,nasal washing and vaginal washing were determined by enzyme-linked immunosorbent assay(ELISA).Results The IgG level in sera of the mice in immunized group reached a peak value(0.257) at 3rd week and was significantly higher than that of in the control group during weeks of 1-4 and 6(F=5.87,P< 0.05).The IgA level in feces of the mice in immunized group reached a peak value(0.054) at 2nd week and was significantly higher than that of in the control group during weeks of 2-4(F=5.87,P< 0.05).The IgA levels in nasal washing and vaginal washing of the mice in immunized group reached the peak values(0.0313,0.0533) at 1st week,then decreased gradually,but were still significantly higher than those in the control group until 12nd week(F=6.15,P< 0.05).Conclusion The immunization with STAg in combination with propolis and IFN-γ by intranasal drip induces high and persistent specific antibody level in mice.