Characterization of Periplasmic Protein BP26 Epitopes of Brucella melitensis Reacting with Murine Monoclonal and Sheep Antibodies

Abstract

More than 35,000 new cases of human brucellosis were reported in 2010 by the Chinese Center for Disease Control and Prevention. An attenuated B. melitensis vaccine M5-90 is currently used for vaccination of sheep and goats in China. In the study, a periplasmic protein BP26 from M5-90 was characterized for its epitope reactivity with mouse monoclonal and sheep antibodies. A total of 29 monoclonal antibodies (mAbs) against recombinant BP26 (rBP26) were produced, which were tested for reactivity with a panel of BP26 peptides, three truncated rBP26 and native BP26 containing membrane protein extracts (NMP) of B. melitensis M5-90 in ELISA and Western-Blot. The linear, semi-conformational and conformational epitopes from native BP26 were identified. Two linear epitopes recognized by mAbs were revealed by 28 of 16mer overlapping peptides, which were accurately mapped as the core motif of amino acid residues 93 DRDLQTGGI 101 (position 93 to 101) or residues 104 QPIYVYPD 111 , respectively. The reactivity of linear epitope peptides, rBP26 and NMP was tested with 137 sheep sera by ELISAs, of which the two linear epitopes had 65–70% reactivity and NMP 90% consistent with the results of a combination of two standard serological tests. The results were helpful for evaluating the reactivity of BP26 antigen in M5-90.

Expression, purification and immunochemical characterization of recombinant OMP28 protein of <i>Brucella</i> species

“…suis, B. ovis, B. canis, B. neotomae and B. melitensis. Recombinant OMP28 was sensitive and specific for diagnosis of Brucella infection in animals by indirect enzyme-linked immunosorbent assay (I-ELISA) (Kumar et al, 2008;Gupta et al, 2010;Thavaselvam et al, 2010;Liu et al, 2011;Dong-Bao et al, 2012;Lim et al, 2012;Qiu et al, 2012;Azizpour et al, 2013;Kim et al, 2013;Xin et al, 2013).…”

Immune responses and protection induced by Brucella suis S2 bacterial ghosts in mice

“…Since 1995 the incidence of human brucellosis has sharply increased in China (Deqiu et al, 2002). Over 35,000 human cases were identified in 2010 by the laboratories of Chinese Center for Disease Control and Prevention (CDC) (Qiu et al, 2012), and about 85% cases were caused by B. melitensis infected sheep or goats (Deqiu et al, 2002;Zhang et al, 2010). Vaccination for animals is considered as the most efficient way to control brucellosis.…”

Brucella melitensis T Cell Epitope Recognition in Humans with Brucellosis in Peru

“…and in Ochrobactrum anthropi. Interestingly, neither BMEI 0536, a well-known immunodominant 26-kDa protein (as determined by antibody response), nor BMEI 0402, a 31-kDa outer membrane protein (6,(35)(36)(37), generated a significant IFN-␥ response by ELISPOT analysis.…”