Discrimination between the anti-monomeric and the anti-multimeric Lewis X response in murine schistosomiasis.

Individuals suffering from schistosomiasis raise an immune response against Galbeta1-4(Fucalpha1-3)GlcNAcbeta (Lewis X, LeX), a trisaccharide that is expressed both in monomeric and polymeric form in different life stages of the schistosomes. In order to study a possible immunological discrimination between different presentations of LeX, i.e. as a monomer or as an oligomer (di- or trimer), the levels of antibodies against lacto-N-fucopentaose III (LNFPIII, a pentasaccharide containing monomeric LeX), and against dimeric and trimeric LeX have been measured in sera of mice with a schistosome infection. The antibody response was predominantly of the IgM type. A striking difference in intensity of the antibody response against monomeric and oligomeric LeX was observed. Furthermore, the antibody response against circulating cathodic antigen (CCA), a schistosomal antigen containing multimeric LeX, was also measured, and the response pattern differed from that of the anti-mono, di- and trimeric LeX responses. In addition, the binding pattern of a panel of monoclonal antibodies (Mabs), derived from mice infected with schistosomes, with LNFPIII, di- and trimeric LeX was measured by surface plasmon resonance (SPR). These Mabs could be divided into three different groups according to their interaction with the LeX oligosaccharides. Based on these data, we suggest that the different presentations of LeX give rise to different groups of anti-LeX antibodies.