An experimental study of BALB/c mice immunized by vaccine gene pcDNA3- PAc against dental caries through different routes / 实用口腔医学杂志

Objective:To observe the anticaries effects of the vaccine gene pcDNA3- PAc against dental caries in BALB/c mice by different routes. Methods: BALB/c mice were immunized with the recombinant plasmid pcDNA3- PAc by the submandibular gland- target injection,the quadriceps femoris injection and the intranasal irrigation respectively. All the mice were immunized two times. The immune interval was two weeks. Saliva and serum samples were collected respectively at 0, 1, 2, 4 weeks after immunization. The specific antibodies were detected by ELISA. Results:The specific antibodies were up at one week after immunization in different routes. The peak time of the antibodies level appeared at 4 weeks.The level of salivary specific anti- PAc IgA induced by submandibular gland- target injection and that of serum IgG induced by thigh bone muscle injection was the highest, respectively. The differences of antibodies level between in experiment groups and negative control group or vacant comparison group were significant(P<0.01). Conclusion: The vaccine gene pcDNA3- PAc effectively induce local mucosal immune response and systemic immune response.

Screening of human phage single chain antibody against the recombinant surface protein of Streptococcus mutans and identification of its biological activities / 中国人兽共患病学报

To isolate human phage single chain antibody against surface protein of Streptococcus mutans,the recombinant surface protein of S.mutans(rAP) was used to coat the immune tubes and the phage single chain antibody was prepared through pDAN5 phage antibody library after 5 rounds of panning.The eluted phage was enriched nearly 30 times.In these ways,13 positive clones were obtained and found to be able to bind with rAP in ELISA assay.Then one of the 13 positive clone phage plasmid was used to infect E.coli HB2151 to induce the expression of the non-fusion single chain antibody (ScFv) with IPTG induction.As demonstrated by SDS-PAGE,the molecular mass of this single chain antibody was proved to be 30 kDa and the amount of expression constituted to 30% of the total bacterial proteins.Apparently,the human phage single chain antibody against surface protein of S.mutans with biological activity was successfully screened.