Use of recombinant Brucella outer membrane proteins 19, 25, and 31 for serodiagnosis of bovine brucellosis.

Aitbay Bulashev,Bakytkali Ingirbay,Zhanbolat Suranshiyev,Alfiya Syzdykova,Orken Akibekov

doi:10.14202/vetworld.2020.1439-1447

Aitbay Bulashev, Bakytkali Ingirbay + Show 3 more

Open Access

https://doi.org/10.14202/vetworld.2020.1439-1447

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Abstract

Background and Aim:Brucellosis remains one of the most common zoonoses. The current anti-brucellosis measures are largely deemed ineffective due to a lack of specificity of conventional serological tests. This study evaluated the use of Brucella outer membrane protein (Omp)19 for serodiagnostic testing.Materials and Methods:The antigenicity of recombinant Brucella Omp19, Omp25, and Omp31 was examined in serum samples from mice and rabbits immunized with Omp19 or Brucella abortus 19 whole cell (WC) and 12 and 152 cows experimentally or naturally infected with brucellosis, respectively. Serum samples were collected from 151 cows that were vaccinated with B. abortus 19 and 12 unvaccinated heifers that were maintained on a brucellosis-free farm.Results:Immunization with Omp19 resulted in antibody production in mice after a single injection without the use of adjuvant. Serum antibodies obtained from rabbits immunized with inactivated B. abortus strain 19 WC targeted Omps by enzyme-linked immunosorbent assay (ELISA) and Western blot. Antibodies targeting Omp19 were identified in all B. abortus strain 544 experimentally infected cows at day 14 post-inoculation (p.i.); Omp25 was detected by ELISA at day 28 p.i., while an ELISA targeting Omp31 was negative for 25% of cows at this time point. Omp19 and Omp25 were readily detected by sera from cows from a new epizootic focus. Antibodies recognizing Omps were also detected in >50% of the animals maintained in a brucellosis-free herd at 10 months after vaccination.Conclusion:Brucella Omp19 in combination with Omp25 and Omp31 may be utilized as target antigens in an ELISA designed for serological testing of unvaccinated cattle.

Highlights

Brucellosis has been identified as a zoonosis that results in significant reductions in livestock productivity, which, in turn, poses a serious threat to human health worldwide
Antibodies targeting Omp19 were identified in all B. abortus strain 544 experimentally infected cows at day 14 post-inoculation (p.i.); Omp25 was detected by enzyme-linked immunosorbent assay (ELISA) at day 28 p.i., while an ELISA targeting Omp31 was negative for 25% of cows at this time point
The immunization schedules used to generate antibodies in mice in Groups III, IV, and V have resulted in an overall increase in antibody production; positive results in the ELISA for rOmp25 and rOmp31 were observed in response to the lowest dilutions of the serum samples from most of the mice immunized with rOmp19 emulsified in Freund’s complete adjuvant (FCA) or Freund’s incomplete adjuvant (FIA)

Summary

Introduction

Brucellosis has been identified as a zoonosis that results in significant reductions in livestock productivity, which, in turn, poses a serious threat to human health worldwide. The disease involves considerable health-care costs and reduces animal productivity; these factors are of significant concern in regions that rely heavily on current economic growth in an effort to reduce poverty [1]. One of the main reasons for the low efficiency of anti-brucellosis measures is the lack of specificity and sensitivity of serological tests used in Copyright: Bulashev, et al Open Access. The Creative Commons Public Domain Dedication waiver (http:// creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. The current anti-brucellosis measures are largely deemed ineffective due to a lack of specificity of conventional serological tests. This study evaluated the use of Brucella outer membrane protein (Omp) for serodiagnostic testing

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