P65 protein, the major immunodominant protein of Mycoplasma hyopneu-moniae (Mhp) exhibiting no cross-reaction with other mycoplasmas, is general y used as a target protein for Mhp detection. In this study, BALB/c mi...P65 protein, the major immunodominant protein of Mycoplasma hyopneu-moniae (Mhp) exhibiting no cross-reaction with other mycoplasmas, is general y used as a target protein for Mhp detection. In this study, BALB/c mice were immunized with prokaryotical y expressed P65 recombinant protein to prepare monoclonal anti-body. After screening with Mhp whole-cel protein and P65 protein, a specific hy-bridoma cel line, 3G12, was obtained by ELISA. Identification results indicated that the antibody secreted by 3G12 hybridoma cel s could react with P65 protein and Mhp whole-cel protein. According to indirect ELISA assay, 3G12 cel culture super-natant possessed a titer of 1∶12 800 against P65 protein and 1∶3 200 against Mhp whole-cel protein; 3G12 ascites possessed a titer of above 1∶4 000 000 against P65 protein and above 1∶20 000 against Mhp 168 whole-cel protein. After long-term in vitro culture and continuous freezing-thawing, 3G12 cel line could stably secrete antibodies. A monoclonal antibody against P65 protein and Mhp whole-cel protein was successful y obtained in the present study, which provided basis for further in-vestigating the pathogenic mechanism of Mhp and establishing diagnostic methods of Mycoplasmal pneumonia of swine (MPS).展开更多
目的:研究甲氨蝶呤(methotrexate,MTX)耐药前后人大肠癌(结直肠癌)HT-29细胞中透明质酸蛋白聚糖连结蛋白1(hyaluronan and proteoglycan link protein 1,HAPLN1)表达的变化及其对MTX耐药性的影响,并探究可能的分子机制。方法:采用浓度...目的:研究甲氨蝶呤(methotrexate,MTX)耐药前后人大肠癌(结直肠癌)HT-29细胞中透明质酸蛋白聚糖连结蛋白1(hyaluronan and proteoglycan link protein 1,HAPLN1)表达的变化及其对MTX耐药性的影响,并探究可能的分子机制。方法:采用浓度梯度递增法构建耐药细胞株HT-29/MTX;RT-PCR检测HAPLN1和多药耐药相关蛋白2(multidrug resistance-associated protein 2,MRP2)的mRNA表达水平;采用脂质体介导法将人HAPLN1和MRP2基因的干扰质粒转染HT-29/MTX细胞并筛选出稳定表达的细胞系;采用CCK-8法检测细胞活力;流式细胞术检测细胞凋亡;采用Western blot检测HAPLN1、MRP2、IκB激酶(IκB kinase,IKK)α/β、p-IKKα/β(Ser176/Ser177)、p65和p-p65(Ser536)的蛋白水平。结果:HT-29/MTX细胞中HAPLN1和MRP2的mRNA和蛋白表达水平都显著高于其亲代HT-29细胞(P<0.05),耐药倍数高达463.756。抑制HAPLN1和MRP2基因表达使MTX对HT-29/MTX细胞的IC_(50)从15.304μmol/L分别降至6.119μmol/L和7.801μmol/L,逆转倍数分别为2.501和1.962,并增强MTX诱导的细胞凋亡(P<0.05)。敲减HAPLN1基因表达和使用IKK抑制剂IKK16均可下调IKKα/β和p65蛋白磷酸化水平以及MRP2蛋白表达水平(P<0.05),但IKK16未对HAPLN1蛋白表达产生影响(P>0.05)。结论:敲减HAPLN1基因表达可在体外增强人大肠癌耐药细胞株HT-29/MTX对MTX的敏感性,这可能与其抑制IKK/p65信号通路活化,继而下调MRP2基因表达有关。展开更多
基金Supported by National Natural Science Foundation of China(31100136,3111339)Independent Innovation Fund of Agricultural Science and Technology of Jiangsu Province[CX(13)3066]~~
文摘P65 protein, the major immunodominant protein of Mycoplasma hyopneu-moniae (Mhp) exhibiting no cross-reaction with other mycoplasmas, is general y used as a target protein for Mhp detection. In this study, BALB/c mice were immunized with prokaryotical y expressed P65 recombinant protein to prepare monoclonal anti-body. After screening with Mhp whole-cel protein and P65 protein, a specific hy-bridoma cel line, 3G12, was obtained by ELISA. Identification results indicated that the antibody secreted by 3G12 hybridoma cel s could react with P65 protein and Mhp whole-cel protein. According to indirect ELISA assay, 3G12 cel culture super-natant possessed a titer of 1∶12 800 against P65 protein and 1∶3 200 against Mhp whole-cel protein; 3G12 ascites possessed a titer of above 1∶4 000 000 against P65 protein and above 1∶20 000 against Mhp 168 whole-cel protein. After long-term in vitro culture and continuous freezing-thawing, 3G12 cel line could stably secrete antibodies. A monoclonal antibody against P65 protein and Mhp whole-cel protein was successful y obtained in the present study, which provided basis for further in-vestigating the pathogenic mechanism of Mhp and establishing diagnostic methods of Mycoplasmal pneumonia of swine (MPS).
文摘目的:研究甲氨蝶呤(methotrexate,MTX)耐药前后人大肠癌(结直肠癌)HT-29细胞中透明质酸蛋白聚糖连结蛋白1(hyaluronan and proteoglycan link protein 1,HAPLN1)表达的变化及其对MTX耐药性的影响,并探究可能的分子机制。方法:采用浓度梯度递增法构建耐药细胞株HT-29/MTX;RT-PCR检测HAPLN1和多药耐药相关蛋白2(multidrug resistance-associated protein 2,MRP2)的mRNA表达水平;采用脂质体介导法将人HAPLN1和MRP2基因的干扰质粒转染HT-29/MTX细胞并筛选出稳定表达的细胞系;采用CCK-8法检测细胞活力;流式细胞术检测细胞凋亡;采用Western blot检测HAPLN1、MRP2、IκB激酶(IκB kinase,IKK)α/β、p-IKKα/β(Ser176/Ser177)、p65和p-p65(Ser536)的蛋白水平。结果:HT-29/MTX细胞中HAPLN1和MRP2的mRNA和蛋白表达水平都显著高于其亲代HT-29细胞(P<0.05),耐药倍数高达463.756。抑制HAPLN1和MRP2基因表达使MTX对HT-29/MTX细胞的IC_(50)从15.304μmol/L分别降至6.119μmol/L和7.801μmol/L,逆转倍数分别为2.501和1.962,并增强MTX诱导的细胞凋亡(P<0.05)。敲减HAPLN1基因表达和使用IKK抑制剂IKK16均可下调IKKα/β和p65蛋白磷酸化水平以及MRP2蛋白表达水平(P<0.05),但IKK16未对HAPLN1蛋白表达产生影响(P>0.05)。结论:敲减HAPLN1基因表达可在体外增强人大肠癌耐药细胞株HT-29/MTX对MTX的敏感性,这可能与其抑制IKK/p65信号通路活化,继而下调MRP2基因表达有关。