Various stages of Schistosoma express Lewis(x), LacdiNAc, GalNAc beta 1-4 (Fuc alpha 1-3)GlcNAc and GalNAc beta 1-4(Fuc alpha 1-2Fuc alpha 1-3)GlcNAccarbohydrate epitopes: detection with monoclonal antibodies that are characterized by enzymatically synthesized neoglycoproteins

We report here that fucosylated epitopes such as Lewis(x), LacdiNAc, fucosy lated LacdiNAc (LDN-F) and GalNAc beta 1-4(Fuc alpha 1-2Fuc alpha 1-3)GlcNA c (LDN-DF) are expressed by schistosomes throughout their life cycle, These four epitopes were enzymatically synthesized and coupled to bovine serum a lbumin to yield neoglycoproteins. Subsequently these neoglycoproteins were used to probe a panel of 188 monoclonal antibodies obtained from infected o r immunized mice, in ELISA and surface plasmon resonance analysis. Of these antibodies, 25 recognized one of the fucosylated structures synthesized, i ndicating that these structures are immunogenic during infection. The MAbs identified could be subdivided in four different groups based on the recogn ition of either the Lewis(x)-, the LacdiNAc-, the LDN-DF-, or both the LDN- F- and LDN-DF epitope. These monoclonal antibodies were then used to invest igate the localization of the fucosylated epitopes in various stages of Sch istosoma mansoni using indirect immunofluorescence. Lewis(x) epitopes were mainly found in the gut and on the tegument of adult worms, on egg shells, and on the oral sucker of cercariae. The LacdiNAc epitope was expressed on the tegument of adult worms, on miracidia, and on the oral sucker of cercar iae. In contrast, LDN-DF epitopes were mainly present in the excretory syst em of adult worms, on miracidia and on whole cercariae. These also stained positive with the LDN-F/LDN-DF epitope antibodies, while whole parenchyma r eacted characteristically only with the latter antibodies. The identificati on of different carbohydrate structures in various stages of schistosomes m ay lead to a better understanding of the function of glycans in the immune response during infection.