Carbohydrate profiling and protein identification of tegumental and excreted/secreted glycoproteins of adult Schistosoma bovis worms

16 pages, 5 figures.-- PMID: 17055171 [PubMed].-- Available online Oct 18, 2006.

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

We would like to thank Dr. Emilio Camafeita Fernández from the Proteomic Unit of the Centro Nacional de Investigaciones Cardiovasculares of Madrid (Spain) for his assistance in mass spectrometry analyses and N. Skinner for supervising the English version of this manuscript. This research was supported by grant AGL2003-04235 from the Ministerio de Educación y Ciencia, Spain.

Peer reviewed