Cassataro Juliana, Pasquevich Karina, Bruno Laura, Wallach Jorge C, Fossati Carlos A, Baldi Pablo C
Laboratorio de Inmunogenética, Hospital de Clínicas, Universidad de Buenos Aires, Buenos Aires, Argentina.
Clin Diagn Lab Immunol. 2004 Jan;11(1):111-4. doi: 10.1128/cdli.11.1.111-114.2004.
Group 3 of outer membrane proteins (OMPs) of Brucella includes Omp25 and Omp31, which share 34% identity. Omp25 is highly conserved in Brucella species, and Omp31 is present in all Brucella species, except Brucella abortus. Antibodies to Brucella melitensis Omp31 have been sought only in infected sheep, and Western blotting of sera from infected sheep did not reveal anti-Omp31 reactivity. We obtained recombinant purified Omp31 (B. melitensis) and tested its recognition by sera from humans and animals suffering from brucellosis by an indirect enzyme-linked immunosorbent assay (ELISA). Serum samples from 74 patients, 57 sheep, and 47 dogs were analyzed; brucellosis was confirmed by bacteriological isolation in all ovine and canine cases and 31 human cases of brucellosis. Thirty-five patients (47%) were positive for antibodies to Omp31, including seven cases of Brucella suis infection, two cases of B. abortus infection, and three cases of B. melitensis infection. Of 39 sheep naturally infected with B. melitensis (biovars 1 and 3), 23 (59%) were positive for antibodies to Omp31. Anti-Omp31 antibodies were also detected in 12 of 18 rams (67%) in which Brucella ovis was isolated from semen. Antibodies to Omp31 were also found in 41 (87%) of the 47 dogs, including 13 with recent infection. These results suggest that an indirect ELISA using recombinant purified Omp31 from B. melitensis would be of limited value for the diagnosis of human and animal brucellosis. Nevertheless, the potential usefulness of this antigen in combination with other recombinant proteins from Brucella should not be dismissed.
布鲁氏菌外膜蛋白（OMPs）的第3组包括Omp25和Omp31，二者的同源性为34%。Omp25在布鲁氏菌属中高度保守，除流产布鲁氏菌外，Omp31存在于所有布鲁氏菌物种中。仅在感染的绵羊中检测了针对羊种布鲁氏菌Omp31的抗体，对感染绵羊血清进行的蛋白质印迹分析未显示出抗Omp31反应性。我们获得了重组纯化的（羊种布鲁氏菌）Omp31，并通过间接酶联免疫吸附测定（ELISA）检测了来自患布鲁氏菌病的人和动物血清对其的识别情况。分析了74例患者、57只绵羊和47只犬的血清样本；所有绵羊和犬的布鲁氏菌病病例以及31例人类布鲁氏菌病病例均通过细菌学分离得以确诊。35例患者（47%）的Omp31抗体呈阳性，其中包括7例猪种布鲁氏菌感染病例、2例流产布鲁氏菌感染病例和3例羊种布鲁氏菌感染病例。在自然感染羊种布鲁氏菌（生物变种1和3）的39只绵羊中，23只（59%）的Omp31抗体呈阳性。在从精液中分离出绵羊布鲁氏菌的18只公羊中，有12只（67%）也检测到了抗Omp31抗体。在47只犬中的41只（87%）中也发现了Omp31抗体，其中13只近期感染。这些结果表明，使用重组纯化的羊种布鲁氏菌Omp31进行间接ELISA对人和动物布鲁氏菌病的诊断价值有限。然而，该抗原与布鲁氏菌的其他重组蛋白联合使用的潜在用途不应被忽视。
