BRUCELLA-ABORTUS CYTOPLASMIC PROTEINS USED AS ANTIGENS IN AN ELISA POTENTIALLY USEFUL FOR THE DIAGNOSIS OF CANINE BRUCELLOSIS

A preparation of Brucella abortus cytoplasmic proteins was depleted of lipopolisaccharyde (LPS) by immunoadsorption with a monoclonal antibo dy (BC68) specific for the O antigen of B. abortus smooth LPS. This ex tract was used as antigen in an indirect ELISA for measuring antiprote in humoral immune response in dogs suffering from brucellosis and in h ealthy controls. All of the affected dogs studied showed IgG antiprote in response, while 2% (2 of 103) of the healthy dogs used as controls gave a positive result. All sera found to be positive by ELISA were al so positive by the rapid slide agglutination test. These preliminary r esults show that the ELISA using B. abortus cytoplasmic proteins could be useful for the specific diagnosis of canine brucellosis.