基因重组乳链球菌防龋疫苗免疫定菌鼠的实验研究

Research of artificial active immunization with gene recombinant Streptococus Lactis vaccine against dental caries in gnotobiotic rats

目的为了阐明基因重组乳链球菌防龋疫苗的免疫效能。方法采用携带有变形链球菌表面蛋白（PAc）结构基因pac的重组乳链球菌防龋疫苗HL107通过灌胃、皮下注射、粘膜下注射三种途径对50只定菌Sprague－Dawley大鼠进行免疫，并以酶联免疫吸附试验进行鼠血清和唾液中抗PAc－IgG、IgA测定。结果通过灌胃进行免疫接种HL107的大白鼠血清中抗PAc－IgG、IgA抗体滴度和唾液中抗PAc－IgA抗体滴度明显高于乳链球菌LM0230免疫组和空白免疫组（P＜0.01）。结论基因重组乳链球菌具有变形链球菌表面蛋白的免疫原性，能够刺激定菌鼠产生特异性免疫反应和免疫表达产物。

Objective To evaluate the level of anti- PAc specific IgG. IgA antibodies in saliva and serum and immungenicity and immunoactivity of gene recombinant S. lactis. Methods 50 Sprague - Dawley rats were immunizedwith the recombinant Streptoccus Lactis HL107 which carries the gene for a surface protein antigen (PAc) of 190kDafrom Streptococcusmutans by intragastric intubation, subcutaneous injection and submucous injection, Saliva and serumsamples were collected and assayed by enayme - linked immunosorbent assay (ELISA). Results The gene recombinantS. lactis HL107 was more effective in inducing significant anti - PA specific serum IgG antibodies and saliva IgA antibodies responses to PAc in gnotobiotic rats when given immunization with HL107 by intragastric way than S. lactis LM 0230immunized rats and non - immunized rats (P < 0.01 ) respectively. Conclusiou The gene recombinant S. lactis possesses an immunogenicity of S.,mutans surface protein antigen and the gene recombinant S. lactis HL107 is able to inducespecifical immune respone in gnotobiotic rats and produce immune expression product.