Objective To construct a lipL32//1-1ipL21-OmpL1//2 fusion gene and its prokaryotic expression system, and to establish an enzyme-linked immunosorbent assay (ELISA) using the rLipL32/1-LipL21-OmpL1/2 fusion antigen o...Objective To construct a lipL32//1-1ipL21-OmpL1//2 fusion gene and its prokaryotic expression system, and to establish an enzyme-linked immunosorbent assay (ELISA) using the rLipL32/1-LipL21-OmpL1/2 fusion antigen of Leptospira interrogans for sensitive and specific detection of IgM in the serum of patients with leptospirosis. Methods lipL32/1-1ipL21-OmpL1/2 fusion genes were constructed using a primer-linking PCFI. The target recombinant protein antigens, rLipL32/1, rLipL21, rOmpL1/2 and rLipL32/1-LipL21-OmpL1/2, were expressed and the purified antigens were then immobilized to the surface of microplate wells for ELISA-based detection of IgM in the sera of leptospirosis patients; Results Of 493 acute leptospirosis patients, 95.7% and 97.8% were positive by rLipL32/1-LipL21- OmpL1/2-1gM-ELISA using different serum dilutions, which was higher than the rLipL32/1-1gM-ELISA (93.1% and 90.3%), rLipL21-1gM-ELISA (90.3% and 87.0%), and rOmpLI-lgM-ELISA (85.6% and 81.1%) (P〈0.01). All IgM-ELISAs tested negative against 56 non-leptospirosis patients with typhoid fever, hemorrhagic fever or dengue fever. Conclusion Trigeminal fusion antigen increases ELISA sensitivity and the rLipL32/1-LipL21-OmpL1/2- IgM-ELISA is a sensitive and specific serological diagnostic method for clinical leptospirosis.展开更多
分别采用Sepharose-6B凝胶过滤层析、Phenyl Sepharose FF疏水作用层析和rProtein A Sepharose亲和层析技术纯化黄鳍棘鲷(Acanthopagrus latus)血清IgM,并将这3种层析纯化方法进行了比较。纯化产物进行SDS-PAGE,电泳结果扫描后经Band Sc...分别采用Sepharose-6B凝胶过滤层析、Phenyl Sepharose FF疏水作用层析和rProtein A Sepharose亲和层析技术纯化黄鳍棘鲷(Acanthopagrus latus)血清IgM,并将这3种层析纯化方法进行了比较。纯化产物进行SDS-PAGE,电泳结果扫描后经Band Scan5.0软件分析显示,单独使用Sepharose-6B凝胶过滤层析或Phenyl Sepharose FF疏水作用层析得到的IgM纯度只有56%左右;二者联合使用纯度可以达到69%,而rProtein A Sepharose亲和层析一步就可以达到89%的纯度;纯化得到的黄鳍棘鲷血清IgM的重链和轻链分子量分别为73.6kD和26.5kD。本研究还以rProtein A Sepharose亲和层析纯化的黄鳍棘鲷血清IgM为抗原,制备其兔抗血清,采用WesternBlot和双向琼脂扩散检测抗血清免疫学活性,并用间接ELISA检测其效价达到1∶25600,为进一步开展黄鳍棘鲷免疫学方面的研究奠定了基础。展开更多
采用盐析法、重组蛋白A(HiTrapr Protein A Sepharose)亲和层析法分离纯化草鱼血清中的IgM,并通过SDS-PAGE及Western-blot技术对纯化蛋白的部分特性进行分析比较并制备兔抗IgM抗血清。结果表明:33%硫酸铵溶液可以沉淀血清中大部分蛋白,...采用盐析法、重组蛋白A(HiTrapr Protein A Sepharose)亲和层析法分离纯化草鱼血清中的IgM,并通过SDS-PAGE及Western-blot技术对纯化蛋白的部分特性进行分析比较并制备兔抗IgM抗血清。结果表明:33%硫酸铵溶液可以沉淀血清中大部分蛋白,但电泳条带仍较多,其中含有78kD和28kD的条带,因此仅可作为免疫球蛋白粗提的方法;而rProtein A亲和层析法所提蛋白则仅有上述重链(78kD)和轻链(28kD)。Western-blot显示,鼠抗人Ig抗体可与78kD及28kD条带发生发应。rProtein A亲和法提纯蛋白的纯度较高,但含量较低,条带较淡,仅可作为实验室小量提纯草鱼IgM的有效方法。将提纯的蛋白免疫实验兔后可制得效价高达1:25600的兔抗鱼IgM血清,并测得血清蛋白总量和IgM含量分别为25.87mg和4.5mg,IgM占血清蛋白总量的17.39%。本实验所采用的蛋白A亲和层析法提取草鱼血清IgM可以方便、快捷地获得高纯度的产物,适合在实验室中纯化鱼类IgM。同时本研究所制备的兔抗草鱼IgM血清也为今后的相关研究工作打下基础。展开更多
目的建立快速检测TORCH-IgM抗体的方法。方法利用聚乙二醇(PEG)能加速抗原、抗体反应的特点,在常规间接EL ISA法检测TORCH-IgM抗体基础上,在样本稀释液、酶标记物稀释液中各加入3%PEG,以缩短反应时间。结果温育时间缩短到15 m in(37℃)...目的建立快速检测TORCH-IgM抗体的方法。方法利用聚乙二醇(PEG)能加速抗原、抗体反应的特点,在常规间接EL ISA法检测TORCH-IgM抗体基础上,在样本稀释液、酶标记物稀释液中各加入3%PEG,以缩短反应时间。结果温育时间缩短到15 m in(37℃)的快速EL ISA法对检测人TORCH-IgM抗体强阳性、弱阳性、阴性标本具有稳定性好,精密性、特异性强的特点;稀释液中不加PEG的常规15 m in法,采用37℃、15 m in试验条件,可能会造成弱阳性标本漏检情况。结论快速EL ISA法的建立为TORCH病原体感染的快速检测和流行病学调查提供了新的手段。展开更多
基金supported by the National Science and Technology Key Program for Infectious Diseases of China (Grant No. 2008ZX10004‐015)the Natural Science Foundation of Zhejiang Medical College in China (No. 2007XZA02)
文摘Objective To construct a lipL32//1-1ipL21-OmpL1//2 fusion gene and its prokaryotic expression system, and to establish an enzyme-linked immunosorbent assay (ELISA) using the rLipL32/1-LipL21-OmpL1/2 fusion antigen of Leptospira interrogans for sensitive and specific detection of IgM in the serum of patients with leptospirosis. Methods lipL32/1-1ipL21-OmpL1/2 fusion genes were constructed using a primer-linking PCFI. The target recombinant protein antigens, rLipL32/1, rLipL21, rOmpL1/2 and rLipL32/1-LipL21-OmpL1/2, were expressed and the purified antigens were then immobilized to the surface of microplate wells for ELISA-based detection of IgM in the sera of leptospirosis patients; Results Of 493 acute leptospirosis patients, 95.7% and 97.8% were positive by rLipL32/1-LipL21- OmpL1/2-1gM-ELISA using different serum dilutions, which was higher than the rLipL32/1-1gM-ELISA (93.1% and 90.3%), rLipL21-1gM-ELISA (90.3% and 87.0%), and rOmpLI-lgM-ELISA (85.6% and 81.1%) (P〈0.01). All IgM-ELISAs tested negative against 56 non-leptospirosis patients with typhoid fever, hemorrhagic fever or dengue fever. Conclusion Trigeminal fusion antigen increases ELISA sensitivity and the rLipL32/1-LipL21-OmpL1/2- IgM-ELISA is a sensitive and specific serological diagnostic method for clinical leptospirosis.
文摘分别采用Sepharose-6B凝胶过滤层析、Phenyl Sepharose FF疏水作用层析和rProtein A Sepharose亲和层析技术纯化黄鳍棘鲷(Acanthopagrus latus)血清IgM,并将这3种层析纯化方法进行了比较。纯化产物进行SDS-PAGE,电泳结果扫描后经Band Scan5.0软件分析显示,单独使用Sepharose-6B凝胶过滤层析或Phenyl Sepharose FF疏水作用层析得到的IgM纯度只有56%左右;二者联合使用纯度可以达到69%,而rProtein A Sepharose亲和层析一步就可以达到89%的纯度;纯化得到的黄鳍棘鲷血清IgM的重链和轻链分子量分别为73.6kD和26.5kD。本研究还以rProtein A Sepharose亲和层析纯化的黄鳍棘鲷血清IgM为抗原,制备其兔抗血清,采用WesternBlot和双向琼脂扩散检测抗血清免疫学活性,并用间接ELISA检测其效价达到1∶25600,为进一步开展黄鳍棘鲷免疫学方面的研究奠定了基础。
文摘采用盐析法、重组蛋白A(HiTrapr Protein A Sepharose)亲和层析法分离纯化草鱼血清中的IgM,并通过SDS-PAGE及Western-blot技术对纯化蛋白的部分特性进行分析比较并制备兔抗IgM抗血清。结果表明:33%硫酸铵溶液可以沉淀血清中大部分蛋白,但电泳条带仍较多,其中含有78kD和28kD的条带,因此仅可作为免疫球蛋白粗提的方法;而rProtein A亲和层析法所提蛋白则仅有上述重链(78kD)和轻链(28kD)。Western-blot显示,鼠抗人Ig抗体可与78kD及28kD条带发生发应。rProtein A亲和法提纯蛋白的纯度较高,但含量较低,条带较淡,仅可作为实验室小量提纯草鱼IgM的有效方法。将提纯的蛋白免疫实验兔后可制得效价高达1:25600的兔抗鱼IgM血清,并测得血清蛋白总量和IgM含量分别为25.87mg和4.5mg,IgM占血清蛋白总量的17.39%。本实验所采用的蛋白A亲和层析法提取草鱼血清IgM可以方便、快捷地获得高纯度的产物,适合在实验室中纯化鱼类IgM。同时本研究所制备的兔抗草鱼IgM血清也为今后的相关研究工作打下基础。
文摘目的建立快速检测TORCH-IgM抗体的方法。方法利用聚乙二醇(PEG)能加速抗原、抗体反应的特点,在常规间接EL ISA法检测TORCH-IgM抗体基础上,在样本稀释液、酶标记物稀释液中各加入3%PEG,以缩短反应时间。结果温育时间缩短到15 m in(37℃)的快速EL ISA法对检测人TORCH-IgM抗体强阳性、弱阳性、阴性标本具有稳定性好,精密性、特异性强的特点;稀释液中不加PEG的常规15 m in法,采用37℃、15 m in试验条件,可能会造成弱阳性标本漏检情况。结论快速EL ISA法的建立为TORCH病原体感染的快速检测和流行病学调查提供了新的手段。