Mature porcine interleukin-2 (pIL-2) gene was amplified by PCR from the plasmid pGEM-T-pIL2 and cloned into the baculovirus pFastBacTM Dual vector of the Bac-to-Bac baculovirus expression system under the control of...Mature porcine interleukin-2 (pIL-2) gene was amplified by PCR from the plasmid pGEM-T-pIL2 and cloned into the baculovirus pFastBacTM Dual vector of the Bac-to-Bac baculovirus expression system under the control of the PH promoter. Recombinant plL-2 (rpIL-2) expressed in Sf9 insect cells was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunofluorescence assay. Western blot analysis confirmed that the rpIL-2 protein had a molecular mass of 20 kDa, which was larger than the molecular mass of the mature protein predicted based on its peptide sequence. The rpIL-2 protein induced in vitro proliferation of ConA-stimulated porcine splenocytes and enhanced in vivo protective immune responses induced by vaccinating the pigs with inactivated oil emulsion vaccine against swine influenza virus. The results showed that the rpIL-2 expressed in Sf9 insect cells has immunoenhancement effects; the finding lays the foundation for the preparation of a specific recombinant IL-2 protein and the development of a novel immune adjuvant of vaccines against various infectious porcine pathogens to increase the immunoprotective efficacy of vaccines.展开更多
While CrylAc has been known to bind with larval midgut proteins cad- herin, APN (amino peptidase N), ALP (alkaline phosphatase) and ABCC2 (adenosine triphosphate-binding cassette transporter subfamily C2), littl...While CrylAc has been known to bind with larval midgut proteins cad- herin, APN (amino peptidase N), ALP (alkaline phosphatase) and ABCC2 (adenosine triphosphate-binding cassette transporter subfamily C2), little is known about the recep- tors of Cry2Ab. To provide a clue to the receptors of Cry2Ab, we tested the baseline cytotoxicity of activated Cry 1Ac and Cry2Ab against the midgut and fat body cell lines of Helicoverpa zea and the ovary cell line ofSpodopterafrugiperda (SFg). As expected, the descending order of cytotoxicity of CrylAc against the three cell lines in terms of 50% lethal concetration (LC50) was midgut (31.0μg/mL) 〉 fat body (59.0μg/mL) and SF9 cell (99.6μg/mL). By contrast, the fat body cell line (LC50 = 7.55μg/mL) was about twice more susceptible to Cry2Ab than the midgut cell line (16.0/xg/mL), the susceptibility of which was not significantly greater than that of SF9 cells (27.0μg/mL). Further, ligand blot showed the binding differences between CrylAc and Cry2Ab in the three cell lines. These results indicated that the receptors of Cry2Ab were enriched in fat body cells and thus largely different from the receptors of CrylAc, which were enriched in midgut cells.展开更多
基金supported by a grant from the the Key Technology R&D Program of China (2008BADB2B01)
文摘Mature porcine interleukin-2 (pIL-2) gene was amplified by PCR from the plasmid pGEM-T-pIL2 and cloned into the baculovirus pFastBacTM Dual vector of the Bac-to-Bac baculovirus expression system under the control of the PH promoter. Recombinant plL-2 (rpIL-2) expressed in Sf9 insect cells was detected by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunofluorescence assay. Western blot analysis confirmed that the rpIL-2 protein had a molecular mass of 20 kDa, which was larger than the molecular mass of the mature protein predicted based on its peptide sequence. The rpIL-2 protein induced in vitro proliferation of ConA-stimulated porcine splenocytes and enhanced in vivo protective immune responses induced by vaccinating the pigs with inactivated oil emulsion vaccine against swine influenza virus. The results showed that the rpIL-2 expressed in Sf9 insect cells has immunoenhancement effects; the finding lays the foundation for the preparation of a specific recombinant IL-2 protein and the development of a novel immune adjuvant of vaccines against various infectious porcine pathogens to increase the immunoprotective efficacy of vaccines.
文摘While CrylAc has been known to bind with larval midgut proteins cad- herin, APN (amino peptidase N), ALP (alkaline phosphatase) and ABCC2 (adenosine triphosphate-binding cassette transporter subfamily C2), little is known about the recep- tors of Cry2Ab. To provide a clue to the receptors of Cry2Ab, we tested the baseline cytotoxicity of activated Cry 1Ac and Cry2Ab against the midgut and fat body cell lines of Helicoverpa zea and the ovary cell line ofSpodopterafrugiperda (SFg). As expected, the descending order of cytotoxicity of CrylAc against the three cell lines in terms of 50% lethal concetration (LC50) was midgut (31.0μg/mL) 〉 fat body (59.0μg/mL) and SF9 cell (99.6μg/mL). By contrast, the fat body cell line (LC50 = 7.55μg/mL) was about twice more susceptible to Cry2Ab than the midgut cell line (16.0/xg/mL), the susceptibility of which was not significantly greater than that of SF9 cells (27.0μg/mL). Further, ligand blot showed the binding differences between CrylAc and Cry2Ab in the three cell lines. These results indicated that the receptors of Cry2Ab were enriched in fat body cells and thus largely different from the receptors of CrylAc, which were enriched in midgut cells.