DNA防龋疫苗经TSG途径免疫BALB/c小鼠实验研究

目的观察编码PAc结构基因A-P片段的重组质粒pCIA-P以经肌肉和颌下腺周围区域皮下注射(TSG)两种途径免疫BALB/c小鼠后的特异性免疫反应,并观察表面蛋白抗原PAc在小鼠颌下腺中的表达。方法将25只BALB/c小鼠随机分为4组,分别以重组质粒pCIA-P经肌肉、颌下腺区周围区域皮下注射两种途径免疫小鼠及pCI质粒和生理盐水肌肉免疫小鼠,ELISA法检测血清和唾液中特异性抗体水平动态变化。将pCIA-P经颌下腺区周围区域皮下注射以免疫组化技术观察表面蛋白抗原PAc。结果颌下腺区皮下注射法免疫后唾液IgA型特异性抗体和血清IgG型特异性抗体均明显升高,并持续数周。肌肉注射法后血清IgG型特异性抗体明显升高,但未有效诱导产生唾液IgA型特异性抗体。在小鼠颌下腺中检测到PAc蛋白的表达。结论重组质粒pCIA-P是一种有效的免疫原,该DNA防龋疫苗经颌下腺周围区域皮下注射免疫是可诱导长期粘膜免疫的有效途径。

The Experimental study of BALB/c Mice Imm(?)miged by Plasmld DNA Encoding S.Mutans Surface Protein PAc Through TSG

Objective To observe immune responses of BALB/c mice after they were immunized with Plasmid DNA pCIA - P encoding S.mutans surface protein Pac by intramuscular injection (i.m.) or targeted salivery gland immunization (TSG) .Plasmid DNA pCIA- P was delivered through TSG and the expression of PAc in submandibular gland was detected. Methods 25 BALB/c mice were immunized with Plasmid pCIA- P by three different routes: intramuscular injection (i.m. ) , targeted salivery gland immunization (TSG) .control mice either were immunized with plasmid pCI or physiological saline by i.m.The dynamic variety of specific antibodies in sera and saliva were checked by ELISA. Immunohistochemistry technique was used to detect the expression of PAc submandibular gland. Results The level of serum specific anti - PAc IgG and salivary specific anti - PAc IgA in TSG immunization groups were significantly higher than those of other groups. And this has continued for several weeks.The i.m. immunization group produced higher level of serum specific anti - PAc IgG significantly than control groups, but failed to induce specifical local mucosal immune response. PAc was expressed in submandibular gland. Conclusions The Plasmid pCIA - P is an effective candidate vaccine.TSG immunization are effective genetic immunization routes to delivery preventing dental caries DNA vaccine and induce long - term local mucosal immune response.