DETECTION OF LIVE AND HEAT-TREATED SALMONELLA-ENTERITIDIS BY A D-1-SEROSPECIFIC ANTILIPOPOLYSACCHARIDE O-9 MONOCLONAL-ANTIBODY

A murine monoclonal antibody 2F11 (IgC(2a)) against Salmonella enterit idis was produced by a fusion of P3X63 Ag8.653 myeloma cells with sple nocytes of a mouse immunized with heat-attenuated (89 degrees C, 20 mi n) S. enteritidis cells. The specificity of this antibody was tested i n an indirect ELISA and sodium dodecyl sulphate polyacrylamide gel ele ctrophoresis followed by immunoblotting. The monoclonal antibody was s pecific to D-1-serogroup Salmonella, exhibiting the highest reactivity with all tested phage types of S. enteritidis (I, 4, 8, 13, and 13a). The monoclonal antibody was reactive with heat-attenuated, as well as live, S. enteritidis cells. In addition, this antibody exhibited high and equal avidity to lipopolysaccharides isolated from S. enteritidis , regardless of phage types. The monoclonal antibody 2F11 proved to be specific to lipopolysaccharide O-9 present in D-1-serogroup Salmonell a. Immunoblotting and ELISA results demonstrated that the epitope reco gnized by this antibody was partially composed of tyvelose and mannose . It was also determined by the nature of glycosidic bonds between mon osaccharides in the polysaccharide backbone region. Employing poly-L-l ysine precoated microplates, this antibody exhibited the detection lim it of 10(4) S. enteritidis cells ml(-1) of buffer, as assessed by ELIS A.