Obtainment and characterization of N-linked glycan structures from high molecular weight components of Ascaris suum extract.

FAVORETTO, B. C. ; JACYCYN J. F.; CASABUONO A. ; .COUTO A. S; FAQUIM-MAUROE. L

Roma

Congreso; ICI 2013. XV Congreso Internacional de Inmunología; 2013

Sociedad Internacional de Inmunología

C-type lectin receptors (CLRs) are part of a heterogeneous superfamily of soluble and transmembrane proteins. They are involved in the homeostase of immune system as well as the recognition of carbohydrate structures in pathogens by immune cells as dendritic cells (DCs). We showed that high molecular weight components (PI) from Ascaris suum are able to modulate the DCs activity. Here, we analyzed the presence of N-linked glycan antigens in PI and its ability to suppress the DCs maturation. The content of N-linked glycan components in PI was obtained by PNGase F treatment and analyzed by HPAEC-PAD and UV-MALDI-TOF. The down-modulatory effect of these glycan components obtained by affinity with ConA-Sepharose was analyzed in DCs incubated with LPS. The HPAEC-PAD results at neutral and acidic conditions revealed several peaks indicating the presence of N-linked oligosaccharide structures with high mannose contents in PI and sialic acid residues, respectively. The UV-MALDI-TOF also confirmed the presence of N-linked glycan components with high-mannose type sugars. The chromatography affinity with ConA showed high content of N-glycosylated components on PI. The flow cytometry results showed that the ConA-linked components inhibited the expression of coestimulatory molecules on DCs induced by LPS compared with those observed on DCs incubated only with LPS. These results indicate that PI contains N-glycosylated structures and these components are able to down-modulate the DCs maturation.