ANTI-LIPID-A MONOCLONAL-ANTIBODY CENTOXIN (HA-1A) BINDS TO A WIDE VARIETY OF HYDROPHOBIC LIGANDS

This note describes the binding specificities of four lipid A monoclon al antibodies (MAbs) including Centoxin (HA-IA); these MAbs display si milar binding properties. MAbs reacted with lipid A and heat-killed sm ooth bacteria, whereas no reactivity was observed with smooth lipopoly saccharide (LPS). Immunoblotting of bacterial extracts separated by so dium dodecyl sulfate-polyacrylamide gel electrophoresis showed that th e MAbs bound to many polypeptide bands including the molecular weight markers. Denaturation of bovine serum albumin (BSA) by boiling or dith iothreitol treatment unmasked antibody epitopes, In addition, binding both to a hydrophobic aliphatic C12 chain covalently coupled to BSA an d to single-stranded DNA was observed. The polyreactivity of these clo nes is most likely mediated by a preferential reactivity with hydropho bic molecular patches.