| In recent years, Adenovirus vectors (AdVs) have been increasingly considered as gene therapy vectors for treating human diseases for the following features: they have been proven safe and effective after being used as live vaccines for immunizing with wild-type (wt) live AdVs showed no significant side effects; they do not integrate their viral DNA into host chromosomes, thereby avoiding the possibility of disturbing vital cellular genes or inducing cancer as has been the case with retrovirus vectors; they can modulate dendritic cell maturation by increasing the expression of major histocompatibility complex (MHC) and costimulating molecules; they can accommodate a large size of foreign DNA of up to 37 kb, and they can be easily produced in large quantities.A growing number of evidence indicates that persistent infection of high-risk HPV, particularly type 16 and 18, is an important initiating agent of cervical carcinogenesis. The south of Xinjiang where Uygur nationality inhabits is a region with a high incidence of cervical cancer, and the women in this region usually suffer cervical cancer much younger than other nationalities. This phenomena is considered as a closely relationship with the infection of HPV-16. The major capsid protein L1 has a conservative protein structure, and can assemble into virus-like particles (VLPs) automatically. So L1 is an ideal target antigen of prophylactic vaccines against cervical cancer.An acellular glycoproteinaceous matrix termed zona pellucida (ZP) surrounds the mammalian oocyte and plays a pivotal role in species-specific sperm–egg recognition and binding, induction of acrosomal exocytosis in ZP-bound spermatozoa, avoidance of polyspermy, and protection of the embryo prior to implantation. The mouse ZP is composed of three biochemically distinct glycoproteins designated as ZP1, ZP2, and ZP3. ZP3, the putative primary sperm receptor, binds to the head region of acrosome-intact spermatozoa and induces acrosomal exocytosis. There is considerable evidence implicate that anti-ZP3 antibodies can block sperm-egg binding, which can be used as an ideal target antigen for immunocontraception.In this study, adenovirus recombinant DNA which carry murine zona pellucida 3 gene and the L1 of HPV-16 from Xinjiang were transfected into HEK 293A cells to package viral particles respectively, the recombinant adenovirus named as Adeno-mZP3 and Adeno-L1. Then Adeno-mZP3, Adeno-L1 and wild type adenovirus were amplified in HEK 293A cells and TCID50 (50% tissue culture infectious doses) assay was employed to detect the titers of viruses. The titer of Adeno-mZP3 is 2.5×1011 PFU/mL, the titer of Adeno-L1 is 1.2×1010 PFU/mL and the titer of wild type Adenovirus is 2.4×1011 PFU/mL. BALB/c mice were immunized three times (interval 14d) with 1×108 PFU Adeno-L1, Adeno-mZP3 and wild type Adenovirus via intragastric route and intranasal route respectively, and the mice immunized with wild type Adenovirus as control. The sera of the mice were collected at 14 d, 28 d and 42 d respectively, and then ELISA tested the level of IgG against L1 and mZP3 respectively. The immunological effects of difeent recombinant adenovirus vaccines and the different immunization routes were analyzed by Two-way ANOVA. The female mice inoculated three times with Adeno-mZP3 were coupled with male mice possessing reproductive capacity to observe the pregnant situation, and then the immunocontraceptive efficacy induced by Adeno-mZP3 was evaluated.The results of ELISA showed that the level of antibody against L1 (or mZP3) from the mice immunized with Adeno-L1 (or Adeno-mZP3) via intranasal (or intragastric route) is extremely higher (P<0.001) than the serumal antibody level of mice in control group at 14th d, 28th d and 42nd d. These results suggested that both Adeno-L1 and Adeno-mZP3 can stimulate humoral immune response via intranasal and intragastric route. However, the serumal antibody of mice immunized via intranasal route was higher than that of mice immunized via intragastric route. Meanwhile antifertility assay indicate that the fertility and mean litter size of mice inoculated with Adeno-mZP3 via intranasal route were reduced significantly, and the mean litter size of mice immunized with Adeno-mZP3 were significantly lower than that of control group (P=0.021<0.05). But the reduction of the fertility and mean litter size of mice inoculated with Adeno-mZP3 via intragastric route was not significant, and the mean litter size of mice immunized with Adeno-mZP3 were not between treatment group and control group were not significantly lower than that of control group (P=0.102>0.05). So it is more effective to immunize mice with recombinant adenovirus via intranasal immunization than intragastric immunization in our study.
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