Dynamics of intestinal lymphocyte in mice treated with complex vaccine against Toxoplasma gondii by intranasal immunization

ObjectiveTo observe the dynamics of intestinal intraepithelial lymphocyte subsets in mice intranasaly immunized with soluble tachyzoites antigen(STAg)in association with propolis and gamma interferon(IFN-γ).MethodsNinety-six female BALB/c mice were randomly divided into immunized and control group and immunized with 2 doses of STAg plus propolis and IFN-γ against Toxoplasma gondii and phosphate buffer,respectively,at an interval of 2 weeks.The mice were killed 1,2,3,4,6,8,10,and 12 weeks after the 2nd dose,respectively,and intestinal intraepithelial lymphocytes (IEL)were isolated and counted.Percentage of CD4⁺ and CD8⁺ T cells was determined by immunocytochemistry.ResultsThe number of IEL of the mice in immunized group reached a peak value at week 2(2.27×10⁵)and was significantly higher than that of in the control group during weeks 1-4(F=8.42,P<0.01).The numbers of CD4⁺ and CD8⁺T cells were both higher than those of the control.CD8⁺ T cells was significantly higher at weeks 1,2,3,4,and 6 than those in the control group (F=6.38,P<0.05),while CD4⁺ T cells in immunized group increased significantly at week 2 and 3(F=5.64,P<0.05). The ratio of CD4⁺/CD8⁺ T cells was higher at week 1 and 2(F=5.74,P<0.05).ConclusionThe immunization with STAg in association with propolis and IFN-γ by intranasal drip can effectively induce immune responses of IEL.