Delivery of human NKG2D-IL-15 fusion gene by chitosan nanoparticles to enhance antitumor immunity.

Nanoparticles are becoming promising carriers for gene delivery because of their high capacity in gene loading and low cell cytotoxicity. In this study, a chitosan-based nanoparticle encapsulated within a recombinant pcDNA3.1-dsNKG2D-IL-15 plasmid was generated. The fused dsNKG2D-IL-15 gene fragment consisted of double extracellular domains of NKG2D with IL-15 gene at downstream. The average diameter of the gene nanoparticles ranged from 200 nm to 400 nm, with mean zeta potential value of 53.8 ± 6.56 mV. The nanoparticles which were loaded with the dsNKG2D-IL-15 gene were uptaken by tumor cells with low cytotoxicity. Tumor cells pre-transfected by gene nanopartilces stimulated NK and T cells in vitro. Intramuscular injection of gene nanoparticles suppressed tumor growth and prolonged survival of tumor-bearing mice through activation of NK and CD8(+) T cells. Thus, chitosan-based nanoparticle delivery of dsNKG2D-IL-15 gene vaccine can be potentially used for tumor therapy.

Membrane-expressed InsB15-23 H-2Kd dtSCT can reduce morbidity of type 1 diabetes mellitus in NOD mice / 中国免疫学杂志

Objective:To illuminate the influence of InsB15-23 H-2Kd dtSCT to the morbidity of type 1 diabetes mellitus in NOD mice.Methods:An eukaryotic plasmid encoded membrane-expressed InsB15-23 H-2Kd dtSCT was inoculated into 3 weeks old female NOD mice subcutaneously and the blood sugar and morbidity of type 1 diabetes mellitus were monitored once a week.To illuminate the cellular mechanism of immunologic intervention of membrane-expressed InsB15-23 H-2Kd dtSCT to the course of type 1 diabetes mellitus in NOD mice,the mononuclear cell infiltration of islets was detected by tissue slice and the frequency of IGRP206 2-14 specific CTLs in PBMC was analyzed by FACs.Results: As compared with pcDNA3.1 (-) control ( 60%) and untreated NOD mice ( 80%) , mice immunized with InsB15-23 H-2Kd dtSCT exhibited low level of islet infiltration and low morbidity in 30 weeks old ( 9%) .But the frequency of IGRP206-214 specific CTLs in PBMC of 16 and 40 weeks old mice showed no difference.Conclusion:Membrane-expressed InsB15-23 H-2Kd dtSCT can protect NOD mice from type 1 diabetes mellitus in IGRP206-214 independent pattern.

Prokaryotic expression of Neisseria gonorrhoeae NspA and its antigenicity / 中华微生物学和免疫学杂志

Objective To develop fast detection techniques for the diagnosis of gonococcal infections.Methods Prokaryotic expression vector for Neisserial surface protein A (NspA) was constructed using the NspA gene cloned by PCR.Mice were immunized with the renatured recombinant NspA (rrNspA)to prepare antibodies against NspA.Western blot and ELISA was used to analyze the binding of NspA antibodies to lysate of gonococcal cells or to intact gonococci.Results NspA antibodies that were prepared by the rrNspA expressed in E.coli could bind to rrNspA,the natural NspA existing in gonococcal cells,or intact gonococci.Conclusion RrNspA and its antibodies have potential value in developing fast diagnostic kits for gonococcal diseases.