为了研究重组猪γ干扰素(r Po IFN-γ)对疫苗免疫效果的影响,试验选取35日龄健康仔猪16只,随机分为4组,1组为对照组,2,3,4组为试验组。各组均免疫PRRS弱毒疫苗1头份,同时1组分点肌肉注射生理盐水4 m L/头;2,3,4组分别分点肌肉注射r Po I...为了研究重组猪γ干扰素(r Po IFN-γ)对疫苗免疫效果的影响,试验选取35日龄健康仔猪16只,随机分为4组,1组为对照组,2,3,4组为试验组。各组均免疫PRRS弱毒疫苗1头份,同时1组分点肌肉注射生理盐水4 m L/头;2,3,4组分别分点肌肉注射r Po IFN-γ注射液4万单位(4 m L)/头、40万单位(4 m L)/头、400万单位(4 m L)/头,研究r Po IFN-γ对PRRS弱毒疫苗血清ELISA抗体和中和抗体产生的影响。结果表明:在免疫PRRS弱毒疫苗后第14天,3组ELISA抗体水平显著高于其他组(P<0.05);试验至第35天,2,3,4组ELISA抗体水平显著高于1组(P<0.05)。免疫PRRS弱毒疫苗21 d后,试验组血清中和抗体水平高于对照组,但各组差异不显著(P>0.05)。说明肌肉注射一定剂量r Po IFN-γ增强了疫苗免疫效果。展开更多
AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine. METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support prod...AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine. METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support productive HBV infection in vitro. Expression of HBsAg and HBeAg in infected HepG2 culture medium was detected by commercial enzyme immunoassays. HBV DNA replication intermediates were detected in infected cells by Southern hybridization and viral DNA load was determined by dot hybridization. RESULTS: IFN-γat 0.1 to 5μg/L efficiently down regulated HBsAg expression in transduced HepG2 cells. At 5μg/L, IFN-γalso suppressed HBV DNA replication in these cells. While treatment with a combination of lamivudine and IFN-γshowed no additive effect, sequential treatment first with lamivudine and then IFN-γwas found to be promising. In this culture system the best HBV suppression was observed with a pulse of 2μmol/L lamivudine for two days, followed by 1μg/L IFN-γfor another four days. Compared to treatment with lamivudine alone, the sequential use of 0.2μmol/L lamivudine for two days, followed by 5μg/L IFN-γfor six days showed a 72% reduction in HBV cccDNA pool. CONCLUSION: This in vitro study warrants further evaluation of a combination of IFN-γand lamivudine, especially in IFN-αnon-responder chronic hepatitis B patients. A reduced duration of lamivudine treatment would also restrict the emergence of drug-resistant HBV mutants.展开更多
文摘目的:研究人重组γ干扰素(Hu-rIFN-7)对小鼠的急性毒性及对大鼠、狗的长期毒性.方法:小鼠肌注或静注Hu-rIFN-γ 4.4×10~9IUm^(-2)观察一周.长期毒性研究中,肌注给予临床推荐剂量1×10~6IU m^(-2)的10,50及100倍(大鼠)及5和50倍(狗),观察血液学、血液生化、尿分析、心电图和组织器官的病理变化.结果:Hu-rIFN-γ对小鼠im或iv的最大耐受剂量为4.4×109 IU m^(-2).长期毒性试验中未发现药物相关的毒性.结论:人重组γ干扰素对大鼠及狗不产生毒性反应.
文摘为了研究重组猪γ干扰素(r Po IFN-γ)对疫苗免疫效果的影响,试验选取35日龄健康仔猪16只,随机分为4组,1组为对照组,2,3,4组为试验组。各组均免疫PRRS弱毒疫苗1头份,同时1组分点肌肉注射生理盐水4 m L/头;2,3,4组分别分点肌肉注射r Po IFN-γ注射液4万单位(4 m L)/头、40万单位(4 m L)/头、400万单位(4 m L)/头,研究r Po IFN-γ对PRRS弱毒疫苗血清ELISA抗体和中和抗体产生的影响。结果表明:在免疫PRRS弱毒疫苗后第14天,3组ELISA抗体水平显著高于其他组(P<0.05);试验至第35天,2,3,4组ELISA抗体水平显著高于1组(P<0.05)。免疫PRRS弱毒疫苗21 d后,试验组血清中和抗体水平高于对照组,但各组差异不显著(P>0.05)。说明肌肉注射一定剂量r Po IFN-γ增强了疫苗免疫效果。
基金Supported by a grant from the Dabur Research Foundation, India and a Senior Research Fellowship of the CSIR, Gov. of India (to MKP)
文摘AIM: To evaluate the in vitro anti-HBV activity of recombinant human IFN-γ, alone and in combination with lamivudine. METHODS: A recombinant baculovirus-HBV/HepG2 culture system was developed which could support productive HBV infection in vitro. Expression of HBsAg and HBeAg in infected HepG2 culture medium was detected by commercial enzyme immunoassays. HBV DNA replication intermediates were detected in infected cells by Southern hybridization and viral DNA load was determined by dot hybridization. RESULTS: IFN-γat 0.1 to 5μg/L efficiently down regulated HBsAg expression in transduced HepG2 cells. At 5μg/L, IFN-γalso suppressed HBV DNA replication in these cells. While treatment with a combination of lamivudine and IFN-γshowed no additive effect, sequential treatment first with lamivudine and then IFN-γwas found to be promising. In this culture system the best HBV suppression was observed with a pulse of 2μmol/L lamivudine for two days, followed by 1μg/L IFN-γfor another four days. Compared to treatment with lamivudine alone, the sequential use of 0.2μmol/L lamivudine for two days, followed by 5μg/L IFN-γfor six days showed a 72% reduction in HBV cccDNA pool. CONCLUSION: This in vitro study warrants further evaluation of a combination of IFN-γand lamivudine, especially in IFN-αnon-responder chronic hepatitis B patients. A reduced duration of lamivudine treatment would also restrict the emergence of drug-resistant HBV mutants.
