The antifertility effects of DNA vaccine-induced immune responses against uroguanylin

Previously we found that uroguanylin displayed a specific expression pattern in the uteri during pregnancy. In this study, the effect of uroguanylin in early pregnancy was studied by DNA vaccine, RT-PCR, Western blot, immunofluorescence and immunohistochemistry. The results showed that (1) the anti-rUfl antibodies could be elicited in the mice after immunization by recombinant plasmid pCR3.1-rUfl; (2) the birth rate of the female mice immunized by pCR3.1-rUfl was significantly reduced (p < 0.01); (3) anti-rUfl antibodies could bind with uroguanylin in the uteri of the non-pregnant mice immunized by pCR3.1-rUfl; (4) in the non-mated experiments, in the uteri of normal, pCR3.1- and pCR3.1-rUfl-immunized mice, expression of p53 and vascular endothelial growth factor (VEGF) was not detected, Bax was expressed, and transforming growth factor beta 1 (TGFβ1) expression was very little; (5) in the mated experiments, p53, Bax, VEGF and TGFβ1 were expressed in the uteri of saline- and pCR3.1-immunized mice that were pregnant. However, their expression was significantly decreased in the uteri of the non-pregnant mice immunized by pCR3.1-rUfl on the 9th day of pregnancy (p < 0.01). The results indicate that the immunization by pCR3.1-rUfl has antifertility effect.