Immunogens of Brucella Abortus 519 Identified By Two-Dimensional Gel Electrophoresis and Immunoblotting

Background: lipopolysaccharides (lpss) and several antigenicproteins of brucella have been considered for preparationof diagnostic reagents and subunit vaccines, the objectiveof this study was to identify and compare immunogens of b.abortus s19 which induce humoral immune responses in human,goat and rabbit.material and methods: the bacterial whole cell extract wasprepared in extraction buffer and resolved using twodimensionalgel electrophoresis (2-de) . the resolved antigenswere reacted against human, goat and rabbit sera using westernblotting ,results: at least 19, 14 and 16 immunogenic proteins were recognizedin western blotting with human, goat and rabbit sera,respectively. the most abundant proteins of the bacterium withimmunogenic properties in goat and rabbit but not in human,were a group of 5-6 proteins with molecular masses of 32-34kda and isoelectric point (pl) ranging from 4.5 to 5.7. in contrast,a group of 5 proteins with molecular weight of 45 kda andpi in the range of 4.5 to 5.4 as well as several low molecularweight proteins were immunogenic in human. furthermore severalproteins of brucella had similar reactions against all sera.conclusion: these results showed that some of the antigenicproteins of brucella could be candidates for more accuratediagnosis of brucellosis in humans and domestic animals.