Proteomic analyses of the time course responses of mice infected withBrucella abortus544 reveal immunogenic antigens

Abstract

Brucellosis is a major zoonotic disease caused by pathogens of the genus Brucella. The eradication of brucellosis in domestic animals, associated with the prevention of human infection, can be attained through accurate diagnosis. However, the conventional serological diagnosis of brucellosis has limitations, particularly in detecting the infection period. Accordingly, the aim of this study was to determine reliable immunogenic proteins to detect Brucella abortus infection according to time course responses to aid in the appropriate management of this disease. Proteomic identification through two-dimensional electrophoresis (2DE), followed by immunoblotting, revealed 13, 24, and 55 immunodominant B. abortus 544 proteins that were reactive to sera from experimentally infected mice at early (10 days), middle (30 days), and late (60 days) infection periods, respectively. After excluding several spots reactive to sera from Yersinia enterocolitica O:9-infected and noninfected mice, 17 of the 67 immunodominant proteins were identified through MALDI-TOF MS. Consequently, the identified proteins showed time course-dependent immunogenicity against Brucella infection. Thus, the results of this study suggest that the production of immunogenic proteins during infection periods improves the diagnosis and discovery of vaccine candidates.

Proteomics of Brucella

“…In this study, five B. abortus S19 proteins (Invasion protein B, Sod, Dps, Ndk, and Bfr) related with antigenicity in naturally infected cattle were identified. In an attempt to analyze time course-dependent immunogenicity against B. abortus 544, 2-DE and immunoblotting with sera from mice infected at early, middle and later times post-infection followed by MALDI-TOF MS, allowed identification of seventeen immunodominant proteins [61]. In order to identify new candidate antigens from B. abortus RB51, a rough mutant lacking the O-polysaccharide, an immunoproteomics approach by 2-DE and immunoblots with sera from infected cattle was performed [62].…”

Proteomics show antigen presentation processes in human immune cells after AS03‐H5N1 vaccination

“…Little overlap of DA proteins between postvaccination days within the same cell type was observed (Supporting Information Figs. S2 and S3), which, while unexpected, could be due to different subsets of proteins being activated at different times in the immune response . Of the 184 unique DA protein families, 54 (29%) were reported for at least two cell types, with human leukocyte antigen (HLA) class I and tubulin, beta 3 class III family‐related proteins being DA in all four cell types (Supporting Information Table S18).…”

Molecular cloning, purification and immunogenicity of recombinantBrucella abortus544 malate dehydrogenase protein

“…In our previous study [ 7 ], several immunogenic proteins were identified through two-dimensional electrophoresis followed by immunoblot analysis of sera from experimentally infected mice in the early, middle and late infection periods with the exclusion of cross-reaction with Yersinia enterocolitica O:9-infected and non-infected mice. One of these specific immunogenic proteins is malate dehydrogenase (MDH), which has been detected in the middle stage of infection in mice.…”

“…As a control, proteins were also incubated using Brucella -negative bovine and mouse sera (1:1000). Brucella -positive sera from our previous studies, which were collected from experimentally infected animals and assessed using the buffered plate agglutination test and Rose Bengal test according to the OIE standard procedures of serological tests for brucellosis, were utilized [ 7 8 ]. The membrane was washed with 1× TBS-T and incubated with horseradish peroxidase-conjugated protein G (1:1000 dilution; Thermo Scientific, USA) for 1 h. The immunogenicity of the recombinant protein was then detected using a luminal-coumaric acid-H 2 O 2 detection solution (ATTO Corporation, Japan) and exposed in a Molecular Imager ChemiDoc XRS+ system machine (Bio-Rad Laboratories).…”

“…In our previous study, malate dehydrogenase (MDH) was one of the immunogenic Brucella proteins reactive in the middle infection period (30 days) with the exclusion of cross-reaction with Y. enterocolitica O:9 and non-infected mouse sera [ 7 ]. This enzyme has been related to B. abortus pathogenesis, which may act as a new virulent factor, and MDH activity can be inhibited using copper, zinc or lead to block the TCA metabolism pathway, which provides new insights to control B. abortus infection [ 14 ].…”