TY - JOUR
T1 - A bacterial engineered glycoprotein as a novel antigen for diagnosis of bovine brucellosis
AU - Ciocchini, Andrés E.
AU - Serantes, Diego A.Rey
AU - Melli, Luciano J.
AU - Guidolin, Leticia S.
AU - Iwashkiw, Jeremy A.
AU - Elena, Sebastián
AU - Franco, Cristina
AU - Nicola, Ana M.
AU - Feldman, Mario F.
AU - Comerci, Diego J.
AU - Ugalde, Juan E.
N1 - Funding Information:
This work was supported by grants PICT Start Up 2010/0144 (Préstamo BID 2437) and FONARSEC NANO 2010 No. 005 from ANPCYT , Argentina.
PY - 2014/8/27
Y1 - 2014/8/27
N2 - Brucellosis is a highly contagious zoonosis that affects livestock and human beings. Laboratory diagnosis of bovine brucellosis mainly relies on serological diagnosis using serum and/or milk samples. Although there are several serological tests with different diagnostic performance and capacity to differentiate vaccinated from infected animals, there is still no standardized reference antigen for the disease. Here we validate the first recombinant glycoprotein antigen, an N-formylperosamine O-polysaccharide-protein conjugate (OAg-AcrA), for diagnosis of bovine brucellosis. This antigen can be produced in homogeneous batches without the need of culturing pathogenic brucellae; all characteristics that make it appropriate for standardization. An indirect immunoassay based on the detection of anti O-polysaccharide IgG antibodies in bovine samples was developed coupling OAg-AcrA to magnetic beads or ELISA plates. As a proof of concept and to validate the antigen, we analyzed serum, whole blood and milk samples obtained from non-infected, experimentally infected and vaccinated animals included in a vaccination/infection trial performed in our laboratory as well as more than 1000 serum and milk samples obtained from naturally infected and S19-vaccinated animals from Argentina. Our results demonstrate that OAg-AcrA-based assays are highly accurate for diagnosis of bovine brucellosis, even in vaccinated herds, using different types of samples and in different platforms. We propose this novel recombinant glycoprotein as an antigen suitable for the development of new standard immunological tests for screening and confirmatory diagnosis of bovine brucellosis in regions or countries with brucellosis-control programs.
AB - Brucellosis is a highly contagious zoonosis that affects livestock and human beings. Laboratory diagnosis of bovine brucellosis mainly relies on serological diagnosis using serum and/or milk samples. Although there are several serological tests with different diagnostic performance and capacity to differentiate vaccinated from infected animals, there is still no standardized reference antigen for the disease. Here we validate the first recombinant glycoprotein antigen, an N-formylperosamine O-polysaccharide-protein conjugate (OAg-AcrA), for diagnosis of bovine brucellosis. This antigen can be produced in homogeneous batches without the need of culturing pathogenic brucellae; all characteristics that make it appropriate for standardization. An indirect immunoassay based on the detection of anti O-polysaccharide IgG antibodies in bovine samples was developed coupling OAg-AcrA to magnetic beads or ELISA plates. As a proof of concept and to validate the antigen, we analyzed serum, whole blood and milk samples obtained from non-infected, experimentally infected and vaccinated animals included in a vaccination/infection trial performed in our laboratory as well as more than 1000 serum and milk samples obtained from naturally infected and S19-vaccinated animals from Argentina. Our results demonstrate that OAg-AcrA-based assays are highly accurate for diagnosis of bovine brucellosis, even in vaccinated herds, using different types of samples and in different platforms. We propose this novel recombinant glycoprotein as an antigen suitable for the development of new standard immunological tests for screening and confirmatory diagnosis of bovine brucellosis in regions or countries with brucellosis-control programs.
KW - Bovine brucellosis
KW - Diagnosis
KW - Recombinant glycoprotein antigen
KW - Serological tests
UR - http://www.scopus.com/inward/record.url?scp=84904765579&partnerID=8YFLogxK
U2 - 10.1016/j.vetmic.2014.04.014
DO - 10.1016/j.vetmic.2014.04.014
M3 - Article
C2 - 24984948
AN - SCOPUS:84904765579
VL - 172
SP - 455
EP - 465
JO - Veterinary Microbiology
JF - Veterinary Microbiology
SN - 0378-1135
IS - 3-4
ER -