Effect of Displaying P277 Peptide on Surface of L-asparaginase on Its Antigenicity and Efficacy of Autoimmune Diabetes Prevention in NOD Mice / 中国生物化学与分子生物学报

ABSTRACT

The recombinant chimeric enzyme of AnsB-TTP-P277 comprising L-asparaginase, a tetanus toxin peptide spacer and P277 was expressed as a soluble protein in Escherichia coli. The purified chimeric enzyme exhibited primary activity of the native asparaginase. Prediabetic NOD mice immunized with the chimeric enzyme could induce specific antibodies against P277 and the specificity of anti-P277 antibodies was verified by Western blot assay. The study showed that displaying the P277 epitope on the surface of asparaginase could effectively overcome the weak antigenicity of the P277 epitope and evoke a strong P277-specific immune response in mice. Moreover, the concentration of blood glucose was measured by an automated analyzer.Histochemical analysis of mice pancreas tissues showed that the administration of the chimeric enzyme to NOD mice could prevent the development of diabetes more efficiently than the peptide P277 itself.