Abstract
Brucellosis, a zoonotic infection caused by the intracellular pathogen Brucella, leads to chronic multi-organ damage. Currently, rapid, accurate, and sensitive diagnostic technologies are crucial for the prevention and control of brucellosis. This study describes the development of a chemiluminescent immunoassay (Bru-CLIA) for sheep and bovine brucellosis antibody detection, utilizing Brucella abortus strain A19 lipopolysaccharide-coated magnetic particles (LPS-MPs) as the serum antigen and acridinium ester-labeled recombinant streptococcal protein G (AE-SPG) for signal generation. After optimizing the assay's parameters, the Bru-CLIA demonstrated a sensitivity of approximately 1 IU/mL and 2 IU/mL for detecting sheep and bovine brucellosis, respectively. No cross-reactivity was observed with sera from animals immunized with Escherichia coli O157:H7, Mycobacterium tuberculosis, Vibrio cholerae, Legionella, Salmonella, Foot and Mouth Disease virus types O and A, Bovine viral diarrhea virus, Sheep contagious pleuropneumonia, Goat pox virus, or Peste des Petits Ruminants virus, indicating strong specificity. The testing of 81 sheep serum samples and 96 bovine serum samples revealed that Bru-CLIA showed 87.65% and 93.75% concordance with the ID-VET commercial kits for sheep and bovine brucellosis detection, respectively. These results demonstrate that Bru-CLIA offers high specificity, sensitivity, repeatability, and reliability, making it a viable rapid diagnostic tool for the epidemiological surveillance of brucellosis.