IMMUNOGENIC PROPERTIES OF MANNOSE-CONTAINING CERAMIDE DISACCHARIDE AND IMMUNOCHEMICAL DETECTION OF ITS HAPTEN IN THE 2 KINDS OF CRUSTACEAN, EUPHAUSIA-SUPERBA AND MACROBRACHIUM-NIPPONENSE

Antiserum against Man-beta-1-4Glc-beta-1-1Ceramide (MlOse2Cer), a mannolipid isolated from spermatozoa of the fresh-water bivalve, Hyriopsis schlegellii, has been elicited in rabbits by repeated injection of a mixture of hapten-bovine serum albumin (1:1, mg/ml) with Freund's adjuvant. The specificity of the affinity-purified antibody (immunoglobulin G type) obtained from the serum was examined, using other glycosphingolipids and glyco-proteins structurally related to MlOse2Cer, by means of ELISA and TLC-immunostaining. The purified antibody was highly specific to MlOse2Cer and lacked reactivity with other glycolipids and glycoproteins including glucosylceramide, lactosylceramide, dimannosylglucosylceramide (MlOse3Cer), glucosaminylmannosylglucosylceramide (ArOse3Cer), thyroglobulin and alpha-1-acid glycoprotein. The antibody was found to bind, although less efficiently, to certain other compounds containing the group Man-beta-1-4Glc and/or Man-beta-1-4GlcNAc at their termini, such as MlOse2-sphingosine and Man-beta-1-4GlcNAc-beta-1-p-aminobenzoic acid ethylester derivatives. The present antibody was applied to the detection of the natural hapten in crustacean glycolipids. The purified antibody reacted with a neutral glycosphingolipid present in the two kinds of crustacean, Euphausia superba (antarctic krill) and Macrobrachium nipponense (fresh-water shrimp) as shown by TLC-immunostaining. The crustacean glycolipid antigen was isolated and characterized to be the Man-beta-1-4Glc-Cer. This is the first report on the presence of a mannose-containing glycosphingolipid in the crustacean.