目的:提高多肽p277的免疫原性,从而提高其对自身免疫性糖尿病的预防作用.方法:将p277 6次重复与Hsp 65融合置于pET28a中构建重组Hsp 65-6×p277表达质粒.该重组质粒在大肠杆菌BL21中以高效可溶形式表达.依次通过细胞裂解、硫酸铵沉淀、双蒸水透析、DEAE纤维素52柱层析纯化获得目的蛋白.用纯化后的融合蛋白Hsp 65-6×p277通过鼻腔给药方式,在不添加任何佐剂的情况下3次免疫4周龄雌性NOD小鼠.每月眼角取血,检测抗体和血糖浓度.结果:初步药效学实验表明融合蛋白Hsp 65-6×p277可抑制NOD小鼠中1型糖尿病的发生.结论:融合蛋白Hsp 65-6×p277有可能发展成为一种具有防治胰岛素依赖性糖尿病作用的疫苗.
AIM: To improve the prevent efficacy of peptide p277 in autoimmune diabetes. METHODS: The recombinant expression plasmid pET28-Hsp65-6×p277 was constructed by inserting 6×p277 which were amplified by PCR into the vector pET28-Hsp65. The plasmid pET28-Hsp65-6×p277 was transformed into E.coli BL21 (DE3) and the fusion protein (Hsp65-6×p277) was expressed effectively as soluble protein after inducing by lactose. The fusion protein was purified and then used to immunize 4-week old female NOD mice with three times of i.n. inoculations in the absence of adjuvants. Serum samples from the immunized mice were collected at monthly interval. The concentrations of blood glucose and antibodies were measured by automatic analyzer. RESULTS: Administration with the Hsp65-6×p277 to NOD mice could prevent the development of diabetes. CONCLUSION: The fusion protein Hsp65-6×p277 might be further developed to a vaccine against insulin-dependent diabetes mellitus.