CHARACTERIZATION OF CORE-OLIGOSACCHARIDE-SPECIFIC AND O-POLYSACCHARIDE-SPECIFIC MONOCLONAL-ANTIBODIES AGAINST AEROMONAS-SALMONICIDA LPS BINDING TO TYPICAL AND ATYPICAL AEROMONAS-SALMONICIDA ISOLATES

Monoclonal antibodies (mAbs) directed against Aeromonas salmonicida ss p, salmonicida (A(+)/F 216.1/83) lipopolysaccharide (LPS) were produce d and characterized. The mAbs 4E8 and 10F4 recognized periodate-resist ant epitope(s) on the O-polysaccharide (O-PS) chains, while mAbs 3G3, 2G11, and 7C4 reacted with periodate-sensitive epitopes(s) on the core -oligosaccharide (core-OS) region of LPS detected by ELISA and immunob lotting. The mAb 7F5 bound to O-PS epitope(s), too, but the recognized epitope(s) are partly periodate-resistant and partly periodate-sensit ive. The three core-OS- and the three O-PS-specific mAbs recognized ep itopes of LPS from all tested ten typical and five atypical A. salmoni cida isolates when assayed by ELISA or immunoblotting, whereas only th e three O-PS-specific mAbs reacted in a dot blot assay. All the O-PS- and the core-OS-specific mAbs bound to the high-molecular sugar compon ent H-2 detected in the LPS fractions of all the A. salmonicida isolat es used (SDS-PAGE and immunoblotting). Consequently, these H-2-compone nts contain core-OS-and O-PS-epitopes. Using the O-PS-specific MAbs, n o reaction was obtained with LPS from bacterial culture supernatants o r whole cell lysates of two A. hydrophila isolates (ELISA, immunoblott ing, dot blotting). However, the core-OS-specific mAbs reacted with A. hydrophila LPS (ELISA, immunoblotting), while dot blot studies did no t result in binding of those mAbs to the bacterial cells. The describe d A. salmonicida LPS-specific MAbs with O-PS- and core-OS-specificity represent valuable tools for using in serodiagnosis or research. (C) 1 997 Elsevier Science B.V.