Production and characterization of KDO-specific monoclonal antibodies recognizing lipopolysaccharides from heptoseless mutants ofSalmonella

Hybrid cell lines producing monoclonal antibodies with specificity for the lipopolysaccharide (LPS) from the deep rough mutant Salmonella minnesota R595 have been established. Spleen cells from BALB/c mice immunized with live R595 bacteria were fused with Sp 2/0 myeloma cells and three hybridomas producing antibodies specific for heptoseless LPS from Salmonella were selected. All three monoclonal antibodies were shown to bind only to heptoseless, but 3-deoxy-d-manno-octulosonic acid (KDO) containing LPS when tested in enzyme-linked immunosorbent assay (ELISA) against a set of structurally defined LPS and lipid A from Salmonella, Shigella and Escherichia coli. Synthetic KDO was an efficient inhibitor of the antibody-R595 LPS interaction defining that KDO is in an immunodeterminant position interacting with the monoclonal antibodies.