葡糖基转移酶合成肽疫苗的免疫原性研究

目的　检测合成的葡糖基转移酶 (glucosyltransferase ,GTF)多肽疫苗的免疫原性 ,有助于研制以合成多肽为基础的防龋疫苗。方法　合成融有GTF催化和葡聚糖结合区的 2 7个氨基酸残基肽段 ,利用ELISA法检测免疫小鼠抗体的产生 ,通过GTF酶活性与变形链球菌粘附实验测定其抗血清的作用。结果　融合多肽疫苗的序列为ANDVDNSNPVVQAEQLYFRANGVQVKG ,免疫小鼠脾脏重量显著增加 ,可有效诱导机体抗体的产生。其免疫血清不仅拮抗GTF的酶活性 ,而且明显抑制变形链球菌的粘附。结论　GTF多肽疫苗可产生抗体介导的抑制GTF酶活性和抑制葡聚糖结合作用 ,对龋病的防治十分有价值

Immunogenicity of a synthetic peptide vaccine from glucosyltransferase

Objective To measure the immunogenicity of a synthetic peptide of glucosyltransferase (GTF) for designing synthetic peptide based vaccine of dental caries. Methods A fusion 27 mer peptide, containing the conserved regions within catalytic and glucan binding domains of GTF, was synthesized. Serum antibodies to the synthetic peptide were determined by ELISA method. Inhibitions of both GTF activity and S. mutans adherence were detected for the functions of antisera. Results The sequence of fusion peptide vaccine was ANDVDNSNPVVQAEQLYFRANGVQVKG. The spleen weights of immunized mice were heavier than the control ones. Specific antibodies were effectually elicited. The immune sera not only inhibited GTF enzymatic activity but also inhibited the vitro adherence of S. mutans . Conclusions The peptide vaccine which involves antibody mediated inhibition of the catalytic and the glucan binding activities of GTF may be valuable for controlling the dental caries.