Efficient uptake of mannosylated proteins by a human Schwann cell line

Autor: Baetas-da-Cruz, Wagner, Alves, Lucinéia, Guimarães, Erick V., Santos-Silva, Alessandra, Pessolani, Maria Cristina V., Barbosa, Helene S., Corte-Rea, Suzana, Cavalcante, Leny A.
Rok vydání: 2009
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Zdroj: DIGITUM. Depósito Digital Institucional de la Universidad de Murcia
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Popis: Complex carbohydrate structures are essential molecules of infectious microbes and host cells, and are involved in cell signaling associated with inflammatory and immune responses. The uptake of mannose-tailed glycans is usually carried out by macrophages, dendritic cells (DCs), and other professional phagocytes to trigger MHC class I- and MHC class II-restricted antigen presentation, and to promote T cell effector responses. Since Schwann cells (SCs) have been proposed as immunocompetent cells, we investigated whether a human cell line (ST88-14 cells) could bind mannosylated ligands in a specific manner. The saturation of uptake of mannosylated molecules by ST88-14 cells and the internalization and distribution pathway of these ligands were tested by cytometry and confocal plus electron microscopy, respectively. This uptake showed a dose-dependent increase, the saturation point being reached at high concentrations of mannosyl residues/240mM mannose. Merging of man/BSA-FITC and S100 labeling showed their partial, but, significant colocalization. Ultrastructural analysis of ST88-14 cells after incubation with HRP-colloidal gold, without or with subsequent chasing at 37°C, showed an initial location on the cell surface and temperature- and time-dependent internalization of the probe. Our findings suggest an efficient mannosylated ligand uptake system through putative lectin(s) that may be operational in inflammatory and immune responses.
Databáze: OpenAIRE