Evaluation of the Contraceptive Potential of brZPCp Vaccine in BALB/c Mice: Their Safety and Efficacy

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 (TGFbeta1) expression was very little; (5) in the mated experiments, p53, Bax, VEGF and TGFbeta1 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.

Immunogenicity of four complementary deoxyribonucleic acid fragments from rabbit zona pellucida 3 and their effects on fertility

OBJECTIVE

To evaluate the exact region in different exons of rabbit zona pellucida (ZP)3 involved in recognition and binding between sperm and the ZP.

DESIGN

Prospective study of a female immunocontraceptive.

SETTING

State Key Laboratory of Reproductive Biology, Institute of Zoology, Chinese Academy of Sciences.

ANIMAL(S)

BALB/C mice.

INTERVENTION(S)

Immunization recombinant vaccines.

MAIN OUTCOME MEASURE(S)

Oocyte immunofluorescence and immunohistochemistry.

RESULT(S)

The immunogenicity and effects on fertility of these four fragments we used were different. Except for the ZP domain, the other three fragments of rabbit ZP3 may be useful as antigen to elicit antibodies. Antiserum was specific and obvious. The fertility of mice after immunization decreased slightly compared with the control.

CONCLUSION(S)

The most effective fragment that is associated with the sperm binding was from sequences contained in exons 5-8 or oligosaccharide linked to this region. Exons 5-8 or oligosaccharide linked to this region may exist outside of the ZP matrix and be safe for use as the antigen. The ZP domain may be not related to the recognition and binding.