Binding studies of a monoclonal antibody specific for 3-deoxy-D-manno-octulosonic acid with a panel of Klebsiella pneumoniae lipopolysaccharides representing all of the O serotypes.

The epitope-specific mAb was tested for inhibition of complement-mediated hemolysis of S. minnesota LPS-sensitized erythrocytes by competition with liquid phase LPS from several K. pneumoniae serotypes. The mAb shows a high level of reactivity with the LPS of all serotypes of K. pneumoniae except O5, O7, O9 and O10. There are also important differences in reactivity with different strains of the same serotype. Reactivity was also tested in direct ELISA, direct hemolysis assay and in Western blot.