Roesler Uwe, Szabo Istvan, Matthies Claudia, Albrecht Kerstin, Leffler Martin, Scherer Kathrin, Nöckler Karsten, Lehmann Jörg, Methner Ulrich, Hensel Andreas, Truyen Uwe
Institute of Animal Hygiene and Environmental Health, Free University Berlin, Berlin, Germany.
Berl Munch Tierarztl Wochenschr. 2011 Jul-Aug;124(7-8):265-71.
The objective of this study was the comparative evaluation of four indirect Salmonella ELISA tests at study time approved in Germany to detect Salmonella infection in pigs.Three tests are based on a LPS-antigen mix and directed against specific IgG antibodies. The fourth test is based on a purified S. Typhimurium whole-cell lysate antigen and discriminates between Salmonella-specific IgM-, IgA-, and IgG- antibodies. In a longitudinal study, two groups of six weeks old hybrid piglets were orally infected with a porcine S. Infantis or S. Derby strain. Clinical and bacteriological parameters were monitored weekly during an observation period of 130 days after infection and serum samples were investigated in parallel with the respective ELISAs. Apparently, the LPS-based ELISA systems used in this study failed to recognize S. Infantis-infected pigs although those animals shed the pathogen in high amounts throughout the study until day 81 post infection (p. i.). In contrast, the isotype-specific Salmonella Typhimurium whole-cell-lysate based ELISA was capable of detecting Salmonella-infected pigs from day ten p. i. at all tested serotypes and revealed the highest sensitivity in detection of S. Infantis-infected pigs. Furthermore, it became apparent that the often used surveillance cut-off value of 40 OD% is not appropriate for intra-vitam detection of S. Infantis- and S. Derby-infected pigs. In contrast, the cut-off values of the ELISAs given by the suppliers result in considerable higher detection rates.
本研究的目的是对德国批准用于检测猪沙门氏菌感染的四种间接沙门氏菌ELISA检测方法进行比较评估。其中三种检测方法基于脂多糖（LPS）抗原混合物，针对特定的IgG抗体。第四种检测方法基于纯化的鼠伤寒沙门氏菌全细胞裂解物抗原，可区分沙门氏菌特异性IgM、IgA和IgG抗体。在一项纵向研究中，两组六周龄的杂交仔猪经口感染猪婴儿沙门氏菌或德比沙门氏菌菌株。在感染后的130天观察期内，每周监测临床和细菌学参数，并同时用相应的ELISA检测血清样本。显然，本研究中使用的基于LPS的ELISA系统未能识别感染婴儿沙门氏菌的猪，尽管这些动物在整个研究期间直至感染后第81天（p.i.）都大量排出病原体。相比之下，基于鼠伤寒沙门氏菌全细胞裂解物的同型特异性ELISA能够在感染后第10天检测出所有测试血清型的沙门氏菌感染猪，并且在检测感染婴儿沙门氏菌的猪时显示出最高的灵敏度。此外，很明显，常用的40 OD%监测临界值不适用于体内检测感染婴儿沙门氏菌和德比沙门氏菌的猪。相比之下，供应商提供的ELISA临界值可导致相当高的检测率。
