Carbohydrate profiling and protein identification of tegumental and excreted/secreted glycoproteins of adult Schistosoma bovis worms (original) (raw)

Schistosoma bovis is a parasite of wild and domestic ruminants that is broadly 31 distributed throughout many tropical and temperate regions of the old world. S. bovis causes 32 severe health problems and significant economic losses in livestock, but in contrast to human 33 schistosomes, S. bovis has been little investigated at a molecular level. Since schistosome 34 glycans and glycoproteins can play important roles in the host-parasite interplay, the aims of the 35 present work were: (i) to characterize the glycans expressed by adult S. bovis worms on their 36 excreted/secreted (ES) and tegumental (TG) glycoproteins, and (ii) to identify their carrier 37 protein backbones by mass spectrometry. Using a panel of lectins and monoclonal and 38 polyclonal anti-glycan antibodies we observed: (i) the absence of sialic acid in S. bovis; (ii) the 39 presence of complex-type N-glycans and LDN antennae on ES glycoproteins; (iii) the presence 40 of glycans containing the Fucα1-2Galβ motif in many TG glycoproteins, and (iv) the presence 41 of glycans containing the Fucα1-3GlcNAc motif on many ES and TG glycoproteins but, 42 simultaneously, the absence of the F-LDN(-F) glycans from both the ES and TG glycoproteins. 43 Interestingly, we also found the Lewis X and Lewis Y antigens co-expressed on several TG 44 isoforms of ATP:guanidino kinase and glyceraldehyde-3-phosphate dehydrogenase. Finally, by 45 ELISA we observed the presence of antibodies against Lewis X , Lewis Y and F-LDN(-F) in the 46 sera of sheep experimentally infected with S. bovis. 47 48