Construction and primary application of Sh-2K~d-HBc tetramer / 中国免疫学杂志

Objective:To prepare and test tetrameric sH-2K~d-HBc complex for the further measurement of the specific CTL response.Methods:PE labled streptavidin with 4 biotinylated binding sites can bind to 4 biotinylated monomer to form the corresponding tetramer.Mice were immunized via different methods of genetic immunization by use of the construted pcDNA3-C plasmid to get the specific CTLs.Then our prepared tetramer was applied to stain the specific CTLs by the analysis of flow cytometry.Results:We applied our prepared tetramer to stain the cells from the experimental groups and control group.The results showed the tetramer was able to discriminate the frequencies of specific CTL induced by the three immunol methods(0.24%,0.26%,0.36% vs 0.07%,P≤0.05).This demonstrated that the prepared tetramer could bind its targets specifically and efficiently.The three immunol methods induced different levels of immune responses.Compared with the traditional muscle injection,gene gun induced weaker humoral immune response and stronger cellular immune response,and hydrodynamic injection induced the strongest humoral and cellular immune responses.Conclusion:Have successfully constructed the sH-2K~d-HBc tetramer.The techniques and methods can be used for preparation of tetramers of other types of MHCⅠ molecules.

Hacia el desarrollo de una vacuna en contra de la cisticercosis porcina basada en la paramiosina de Taenia solium

La paramiosina de Taenia solium (TPmy) es un antígeno inmunodominante de la cisticercosis humana y porcina. Se trata de una proteína de 100 kDa con una estructura alfa-hélice superenrollada asociada al músculo y a estructuras tegumentarias del cisticerco. La TPmy tiene la propiedad de unirse al C1q e inhibir la cascada del complemento. La TPmy probablemente se une al C1q a través sus dominios tipo colágena y podría estar relacionada con una estrategia parasitaria para modular la respuesta inmune del huésped. En el hombre y en el ratón, la respuesta inmune humoral en contra de la TPmy está preferentemente dirigida hacia el extremo carboxilo terminal mientras que el extremo amino terminal de la TPmy induce una respuesta protectora celular de tipo Th1. Ensayos de protección en el modelo murino de cisticercosis en ratones inmunizados con fragmentos recombinantes de TPmy revelaron que el extremo amino terminal induce alrededor de 60% de protección en contra de un reto intraperitoneal con cisticercos de Taenia crassiceps. Ensayos preliminares de protección por inmunización génica revelaron que el extremo amino terminal de la TPmy clonado en un vector plasmídico con un promotor de citomegalovirus induce alrededor de 79% de protección, junto con plásmidos para la expresión de IL-12, sugiriendo que este tipo de inmunización con TPmy puede resultar en el desarrollo de una vacuna eficaz y económica en contra de la cisticercosis.

Taenia solium paramyosin (TPmy) is a prominent 100 kDa antigen in human and porcine cysticercosis. TPmy is an α-helical coiled coil protein present in muscle and tegumentary structures of T. solium cysticerci. TPmy has the property of binding C1q resulting in inhibition of the complement cascade. TPmy probably binds C1q through its collagen-like domains and could be involved in a parasite strategy to modulate host immune response. Humoral immune response against TPmy is preferentially directed against carboxyl terminal end in humans and mice, whereas amino terminal end of TPmy preferentially induces a Th1-related cellular immune response. Protection studies in murine model of cysticercosis showed that the amino terminal end fragment of TPmy induces approximately 60% protection against an i.p. challenge with Taenia crassiceps cysts when mice are immunized with recombinant fragments of TPmy. Initial protection studies using genetic immunization showed that amino terminal end fragment of TPmy cloned into a plasmid expression vector with a cytomegalovirus promoter, together with IL-12-expressing plasmids induced 79% protection, suggesting that this kind of TPmy-immunization might result in development of a cost-effective vaccine against cysticercosis.

The study on production of anti-thrombomodulin antibodies using genetic immunization / 中华检验医学杂志

Objective To produce anti-thrombomodulin antibodies.Methods Using genetic immunization: Eukaryotic expression plasmid pcDNA3.1/TM(LEO),encoding all the extracellular domain of human thrombomodulin and signal peptides but lacking the transmembrance and cytoplasmic domains was constructed, which recombinant thrombomodulin was secreted soluble product. The plasmid was isolated from large-scale bacterial cultures by treatment with alkali and SDS, purified by precipitation with polyethylene Glycol (PEG). Recombinant plasmid was injected into tibial muscle of BALB/c mice. The productions of TM and anti-TM have been detected. Results The positive of RT-PCR and expressed TM identified the function of the recombinant plasmid. The pcDNA3.1/TM(LEO) induced higher titer of anti-TM. The antibody titer peaked between the 5th and 7th injection with a titer of 1∶8 000 detected by cell-ELISA coated with EVC-304. Specificity has been identified by western blot and immunohistochemistry.Conclusion The production of antibody through genetic immunization was a feasible method due to the difficulties in obtaining and purification of natural thrombomodulin.

Production of anti-human c-kit monoclonal antibodies by direct intra-spleen injection of DNA vaccine / 中国免疫学杂志

Objective:To prepare anti-human c-kit monoclonal antibody(McAb) by genetic immunization in spleen,and to determine practicability of these means to produce McAbs based on the biological activity of anti-human c-kit antibody.Methods:Recombinant plasmid pcDNA3.1/c-kit extracellular domain was constructed by molecular cloning techniques,and was used to immunize BALB/c mice in spleen directly to prepare mAb against human c-kit by routine hybridoma technique.FASC、fluorescence microscope and Western blot were utilized to identify the prepared antibody.Results:c-kit extracellular region was cloned and insert pcDNA3.1 plasmid successfully.Three hybridoma cell lines 6C4、2C5 and 5D5 that secrete anti-human c-kit McAbs were obtained after using intra-spleen immunization with a DNA vaccine.The isotypes of these three antibodies were all IgM,and the epitopes were different with each other.Conclusion:The method of genetic immunization into spleen can be used to prepare anti-human c-kit monoclonal antibodies.

Study on antitumor effect by gene immunization of the chimeric HBV and HCV / 中国免疫学杂志

Objective:To observe the specific cellular immune response and the protection against P815 mastovytoma cells(H 2 d) stable expressing HBV surface antigen and HCV core antigen after the immunized mice(H 2 d) with plasmids SpcDNA3.1,CpcDNA3.1 and chimeric plasmid CSpcDNA3.1.Methods:After subcutaneous immunization with the three plasmids SpcDNA3.1,CpcDNA3.1 and CSpcDNA3.1 respecitively 3 w,the mice were inoculated with the transfected P815 tumor cells.The tumors size and the survival rate were measured.CTL assay was detected with LDH methods.Results:The chimeric plasmid CSpcDNA3.1 could inhibit the tumor growth,prolong the survival period and improve the survivial rate evidently.The splencytes from immunized mice showed strong CTL activity to CSpcDNA3.1 transfected P815 tumor cells.Conclusion:It was suggestd that specific antitumor cellular immunity could be induced by immunization with the chimeric plasmid CSpcDNA3.1 that contain chimeric HBV and HCV gene.

Genetic immunization of BALB/c mice with extracellular domains of human TSH receptor provides a model of Graves' disease / 中国免疫学杂志

0.05).Conclusion:The pcDNA3.1/hTSHR has been successfully constructed.Animal models of Graves' disease have been made successfully by genetic immunization.

Preparation and identification of mouse polyclonal antibody against human Nanog / 解放军医学杂志

Objective To prepare mouse polyclonal antibody against human Nanog by genetic immunization and to identify this antibody by Western blot and immunofluorescence. Method The antigenicity fragment (A16-V101) of human Nanog (hNanog) was chosen by analysis of Accelrys software, and its cDNA (258bp) was amplified from plasmid containing full-length cDNA of hNanog, then it was cloned into pBQAP-TT to construct recombinant plasmid pBQAP-TT-hNanog for genetic immunization. Mice were immunized with this recombinant plasmid and two other adjuvant plasmids-pCMVi-GMCSF and pCMVi-FIT3L, which help to enhance the antibody's generation. After 12 weeks, we obtained mouse anti-hNanog antibody from mice blood serum. The antibody titer was determined by enzyme-linked immunoadsordent assay (ELISA), and its specificity was identified by Western blot in human renal protein. Using this antibody, we detected hNanog expression in HKC cells of hNanog-AAV2 transfection. Results Recombinant plasmid pBQAP-TT-hNanog for genetic immunization was confirmed to be correct by restriction digestion and sequencing. The result of ELISA showed that the antibody titer was 1∶3 200. This antibody recognized a band of 34kD hNanog protein in human renal protein by Western blot. Immunofluorescence showed that Nanog protein was mainly located in the nuclei in hNanog transgene HKC cells. Conclusion Genetic immunization can offer mouse anti-hNanog polyclonal antibody of high titer and high specificity.