Bowden R A, Cloeckaert A, Zygmunt M S, Bernard S, Dubray G
Laboratoire de Pathologie Infectieuse et Immunologie, Centre de Recherches de Tours, Institut National de la Recherche Agronomique, Nouzilly, France.
Infect Immun. 1995 Oct;63(10):3945-52. doi: 10.1128/iai.63.10.3945-3952.1995.
Seven surface-exposed outer membrane proteins (OMPs) in Brucella supp. have been previously described (A. Cloeckaert, P. de Wergifosse, G. Dubray, and J. N. Limet, Infect. Immun. 58:3980-3987, 1990). OMPs were shown to be more accessible to monoclonal antibodies (MAbs) on rough (R) Brucella melitensis and B. abortus strains than to MAbs on their smooth (S) counterparts. In this work, we have extended this study to representatives of the main Brucella species, using MAbs specific for OMPs and S and R lipopolysaccharides (S-LPS and R-LPS). Enzyme-linked immunosorbent assay (ELISA), flow cytometry, and immunoelectron microscopy showed important differences between strains in the binding of OMP- and R-LPS-specific MAbs which were in part related to the particular expression of S-LPS, irrespective of the species. Results indicated that both the amount and the length of O polysaccharide on S-LPS greatly influenced the accessibility of OMP and R-LPS epitopes to MAbs. S-R B. melitensis EP and S B. suis 40, for instance, which express O-polysaccharide chains in small amounts and with short mean length, respectively, bound a greater number of OMP- and R-LPS-specific MAbs than the other S Brucella strains. The major 31- to 34-kDa OMP was the most exposed OMP on S strains of B. melitensis and B. suis. In most cases, flow cytometry results agreed with those of ELISA and supplied additional data, such as the homogeneity or heterogeneity of OMP expression at the strain level. However, there were some discordances between flow cytometry and ELISA results concerning the surface exposure of the 25- to 27-kDa and 31- to 34-kDa OMPs on S strains and that of minor OMPs in vaccine strain B. melitensis Rev.1. Immunoelectron microscopy confirmed the poor accessibility of OMPs to MAbs on the surface of S Brucella strains. The naturally R pathogenic species B. ovis and B. canis bound the majority of OMP-specific MAbs as well as the R-LPS-specific MAbs. Therefore, the conserved OMP and R-LPS epitopes could play a role as targets of protective antibody-mediated immunity in infections caused by naturally R B. ovis and B. canis.
先前已描述了布鲁氏菌属中的七种表面暴露外膜蛋白（OMPs）（A. Cloeckaert、P. de Wergifosse、G. Dubray和J. N. Limet，《感染与免疫》58:3980 - 3987，1990年）。结果表明，与光滑型（S）布鲁氏菌菌株相比，粗糙型（R）马尔他布鲁氏菌和流产布鲁氏菌菌株上的OMPs对单克隆抗体（MAbs）更易接近。在本研究中，我们使用针对OMPs以及S和R脂多糖（S - LPS和R - LPS）的单克隆抗体，将该研究扩展至主要布鲁氏菌物种的代表菌株。酶联免疫吸附测定（ELISA）、流式细胞术和免疫电子显微镜显示，OMP和R - LPS特异性单克隆抗体结合情况在菌株间存在重要差异，这部分与S - LPS的特定表达有关，与物种无关。结果表明，S - LPS上O多糖的数量和长度极大地影响了OMP和R - LPS表位对单克隆抗体的可及性。例如，马尔他布鲁氏菌EP S - R和猪布鲁氏菌40 S，分别少量表达平均长度较短的O - 多糖链，它们比其他S型布鲁氏菌菌株结合更多的OMP和R - LPS特异性单克隆抗体。主要的31至34 kDa OMP是马尔他布鲁氏菌和猪布鲁氏菌S型菌株上最易暴露的OMP。在大多数情况下，流式细胞术结果与ELISA结果一致，并提供了额外数据，如菌株水平上OMP表达的同质性或异质性。然而，在S型菌株上25至27 kDa和31至34 kDa OMP的表面暴露以及疫苗株马尔他布鲁氏菌Rev.1中次要OMP的表面暴露方面，流式细胞术和ELISA结果存在一些不一致。免疫电子显微镜证实了S型布鲁氏菌菌株表面的OMPs对单克隆抗体的可及性较差。天然粗糙型致病物种绵羊布鲁氏菌和犬布鲁氏菌结合了大多数OMP特异性单克隆抗体以及R - LPS特异性单克隆抗体。因此，保守的OMP和R - LPS表位可能在天然粗糙型绵羊布鲁氏菌和犬布鲁氏菌引起的感染中作为保护性抗体介导免疫的靶点发挥作用。
