Electrophoretic resolution of microheterogeneity in Vibrio cholerae lipopolysaccharide

The construction of a monoclonal diagnostic system for the field detection of Vibrio cholerae

An enzyme-based double monoclonal field diagnostic system detecting both serotypes of Vibrio cholerae has been developed. The system uses nitrocellulose as a solid support, 1.25% skimmed dried milk as blocking reagent, water as washing reagent, and alkaline phosphatase cross-linked to antibody by means of glutaraldehyde as detecting reagent. The sensitivity of the system was 10(5) vibrios/ml. The biotin-avidin system gave sensitivity an order of magnitude weaker. There were no cross-reactions with the range of other bacteria tested.

Unusual cross-reactions among monoclonal antibodies to bacterial antigens: idiotypic and competitive binding analysis

In a previous study, we have described unusual cross-reactions among monoclonal antibodies (Mabs) to bacteria and in particular to the Inaba and Ogawa serotypes of Vibrio cholerae. In this study, the extent to which the binding sites of both antibodies and antigens overlap has been investigated by competitive binding and idiotypic analysis. The competitive binding data indicate that the cross-reactive binding of the Inaba Mabs to the Ogawa vibrios can be abolished by incubation with higher affinity Ogawa Mabs. However, rabbit antiserum raised against the Inaba series does not react with the Ogawa series, indicating that anti-Inaba Mabs do not share idiotypic determinants with anti-Ogawa Mabs. The results therefore suggest that the two sets of antibodies recognise different determinants which are closely related in spatial terms, and which consequently do not permit simultaneous binding of the two types of monoclonal antibody.