Dynamics of Specific Antibody Induced with Mucosal Complex Vaccine against Toxoplasma gondii in Mice by Intranasal Immunization

Objective To observe the dynamics of IgG in sera as well as IgA in fecal and nasal washing of mice immunized with mucosal complex vaccine against Toxoplasma gondii by intranasal drip and explore the mechanism of the vaccine against infection with Toxoplasma gondii.Methods Ninty-six BALB/c mice were randomly divided into test and control groups and immunized with 2 doses of mucosal complex vaccine against Toxoplasma gondii and PBS respectively,at an interval of 2 weeks.Kill the mice on weeks 1,2,3,4,6,8,10 and 12 after the 2nd dose respectively and determine the IgG in sera as well as IgA in fecal and nasal washing by ELISA.Results The IgG level in sera of mice in test group reached a peak value at week 3 and was significantly higher than that in control groups during weeks 1-4,6 and 8.The IgA level in fecal of mice in test group reached a peak value at week 2 and was significantly higher than that in control group during weeks 2-4.However,the IgA level in nasal washing of mice in test group reached a peak value at week 1 then decreased gradually,but was still significantly higher than that in control group until week 12.Conclusion The immunization with mucosal complex vaccine against Toxoplasma gondii by intranasal drip induced high and persistent specific antibody level in mice.