OBJECTIVE: To characterize the immune response induced by SAG1 encoding plasmid combined with IL-2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis. METHODS: Mice wer...OBJECTIVE: To characterize the immune response induced by SAG1 encoding plasmid combined with IL-2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis. METHODS: Mice were co-injected intramuscularly with plasmid encoding Toxoplasma gondii SAG1 plus murine IL-2 expression vector at a dose of 100 microg. Booster immunizations were employed 2 more times at 3-week interval. As controls, mice were inoculated with PBS or empty plasmid pcDNA3. Humoral and cellular responses were assayed using ELISA for the determination of Ab, Ab isotype and IFN-gamma, as well as IL-4. To detect the integration and dissemination of DNA in the injected mice, PCR and in situ hybridization were performed. All mice were then infected with highly virulent RH tachyzoites of Toxoplasma gondii intraperitoneally. RESULTS: Significant increases in specific IgG levels were observed in mice after immunization three times with SAG1 expression plasmid. With respect to the IgG isotype, co-inoculation of IL-2 expression plasmid enhanced the level of IgG2a and the production of IFN-gamma. Challenging mice by vaccinating with combined plasmids with RH tachyzoites resulted in prolonged survival. CONCLUSION: Humoral and cytokine responses elicited by SAG1 DNA immunization can be modulated by co-inoculation with IL-2 expression plasmid. The use of DNA vaccine in combination with an appropriate cytokine gene to prevent T. gondii infection warrants further investigation.展开更多
Objective To construct the eukaryotic expression recombinant plasmid, pcIFN γ, as a genetic adjuvant and observe the immune responses elicited by pcDNA3 rhoptry protein 1 (pc ROP1) combined with pcIFN γ aga...Objective To construct the eukaryotic expression recombinant plasmid, pcIFN γ, as a genetic adjuvant and observe the immune responses elicited by pcDNA3 rhoptry protein 1 (pc ROP1) combined with pcIFN γ against Toxoplasma gondii (T gondii) infection in mice Methods A fragment of the IFN γ gene was directly inserted into the pcDNA3 plasmid and identified by two restriction endonucleases digestion pcIFN and pcROP1 DNA was injected into the left leg muscle of mice at a dosage of 100?μg, and a booster vaccination was given at the same dosage after two weeks Control groups were injected with pcDNA3 blank plasmid or normal saline At 30, 50 and 70 days after booster injection, kinetic tests were carried out: MTT assay for the proliferation response of T lymphocyte cells and the activity of NK cells, sandwich ABC ELISA for the determination of IFN γ, IL 2 and IL 10; a serum enzymetic aassay for nitric oxide (NO) in sera and ELISA for the titer of IgG antibody in sera Results The recombinant plasmid, pcIFN γ was constructed The proliferation response of spleen T lymph cells, NK cell killing activity, and serum levels of IFN γ, IL 2 and NO in mice injected with pcROP1 and pcIFN γ were higher than in those injected with pcROP1 alone There was no difference in IgG antibody levels between the two groups Conclusion The genetic adjuvant, pcIFN γ, could enhance the cellular immune response induced by DNA vaccine of pcROP1 in mice against Toxoplasma gondii infection展开更多
To characterize the immune response induced by SAG1 encoding plasmid combined with IL 2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis Methods Mice were co inje...To characterize the immune response induced by SAG1 encoding plasmid combined with IL 2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis Methods Mice were co injected intramuscularly with plasmid encoding Toxoplasma gondii SAG1 plus murine IL 2 expression vector at a dose of 100 μg Booster immunizations were employed 2 more times at 3 week interval As controls, mice were inoculated with PBS or empty plasmid pcDNA3 Humoral and cellular responses were assayed using ELISA for the determination of Ab, Ab isotype and IFN γ, as well as IL 4 To detect the integration and dissemination of DNA in the injected mice, PCR and in situ hybridization were performed All mice were then infected with highly virulent RH tachyzoites of Toxoplasma gondii intraperitoneally Results Significant increases in specific IgG levels were observed in mice after immunization three times with SAG1 expression plasmid With respect to the IgG isotype, co inoculation of IL 2 expression plasmid enhanced the level of IgG2a and the production of IFN γ Challenging mice by vaccinating with combined plasmids with RH tachyzoites resulted in prolonged survival Conclusion Humoral and cytokine responses elicited by SAG1 DNA immunization can be modulated by co inoculation with IL 2 expression plasmid The use of DNA vaccine in combination with an appropriate cytokine gene to prevent T gondii infection warrants further investigation展开更多
文摘OBJECTIVE: To characterize the immune response induced by SAG1 encoding plasmid combined with IL-2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis. METHODS: Mice were co-injected intramuscularly with plasmid encoding Toxoplasma gondii SAG1 plus murine IL-2 expression vector at a dose of 100 microg. Booster immunizations were employed 2 more times at 3-week interval. As controls, mice were inoculated with PBS or empty plasmid pcDNA3. Humoral and cellular responses were assayed using ELISA for the determination of Ab, Ab isotype and IFN-gamma, as well as IL-4. To detect the integration and dissemination of DNA in the injected mice, PCR and in situ hybridization were performed. All mice were then infected with highly virulent RH tachyzoites of Toxoplasma gondii intraperitoneally. RESULTS: Significant increases in specific IgG levels were observed in mice after immunization three times with SAG1 expression plasmid. With respect to the IgG isotype, co-inoculation of IL-2 expression plasmid enhanced the level of IgG2a and the production of IFN-gamma. Challenging mice by vaccinating with combined plasmids with RH tachyzoites resulted in prolonged survival. CONCLUSION: Humoral and cytokine responses elicited by SAG1 DNA immunization can be modulated by co-inoculation with IL-2 expression plasmid. The use of DNA vaccine in combination with an appropriate cytokine gene to prevent T. gondii infection warrants further investigation.
文摘Objective To construct the eukaryotic expression recombinant plasmid, pcIFN γ, as a genetic adjuvant and observe the immune responses elicited by pcDNA3 rhoptry protein 1 (pc ROP1) combined with pcIFN γ against Toxoplasma gondii (T gondii) infection in mice Methods A fragment of the IFN γ gene was directly inserted into the pcDNA3 plasmid and identified by two restriction endonucleases digestion pcIFN and pcROP1 DNA was injected into the left leg muscle of mice at a dosage of 100?μg, and a booster vaccination was given at the same dosage after two weeks Control groups were injected with pcDNA3 blank plasmid or normal saline At 30, 50 and 70 days after booster injection, kinetic tests were carried out: MTT assay for the proliferation response of T lymphocyte cells and the activity of NK cells, sandwich ABC ELISA for the determination of IFN γ, IL 2 and IL 10; a serum enzymetic aassay for nitric oxide (NO) in sera and ELISA for the titer of IgG antibody in sera Results The recombinant plasmid, pcIFN γ was constructed The proliferation response of spleen T lymph cells, NK cell killing activity, and serum levels of IFN γ, IL 2 and NO in mice injected with pcROP1 and pcIFN γ were higher than in those injected with pcROP1 alone There was no difference in IgG antibody levels between the two groups Conclusion The genetic adjuvant, pcIFN γ, could enhance the cellular immune response induced by DNA vaccine of pcROP1 in mice against Toxoplasma gondii infection
文摘To characterize the immune response induced by SAG1 encoding plasmid combined with IL 2 gene adjuvant in mice and to assess the protective effect of this vaccination against toxoplasmosis Methods Mice were co injected intramuscularly with plasmid encoding Toxoplasma gondii SAG1 plus murine IL 2 expression vector at a dose of 100 μg Booster immunizations were employed 2 more times at 3 week interval As controls, mice were inoculated with PBS or empty plasmid pcDNA3 Humoral and cellular responses were assayed using ELISA for the determination of Ab, Ab isotype and IFN γ, as well as IL 4 To detect the integration and dissemination of DNA in the injected mice, PCR and in situ hybridization were performed All mice were then infected with highly virulent RH tachyzoites of Toxoplasma gondii intraperitoneally Results Significant increases in specific IgG levels were observed in mice after immunization three times with SAG1 expression plasmid With respect to the IgG isotype, co inoculation of IL 2 expression plasmid enhanced the level of IgG2a and the production of IFN γ Challenging mice by vaccinating with combined plasmids with RH tachyzoites resulted in prolonged survival Conclusion Humoral and cytokine responses elicited by SAG1 DNA immunization can be modulated by co inoculation with IL 2 expression plasmid The use of DNA vaccine in combination with an appropriate cytokine gene to prevent T gondii infection warrants further investigation
