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Cryptococcus neoformans is a fungal pathogen causing life-threatening meningoencephalitis in immunocompromised individuals, such as AIDS patients. Several Cryptococcal mannoproteins (MPs), such as MP98, 88, and 84, are reported as key antigens stimulating host CD4 (+) T-cell response. In this study, we investigated the effect of N-glycans of Cryptococcal MPs on the interaction with host cells. The expression pattern analysis of the GPI-anchorless MPs with His (H)-tag in the wild-type (WT) and various N-/O-glycosylation mutant strains of C. neoformans indicated that MP98 is modified mainly by N-glycosylation, while MP88 and MP84 are subject to both N- and O-glycosylation. The in vitro adhesion assay using the purified MP(H)s revealed that compared to the WT-secreted MPs, the MP98(H) and MP84(H) proteins secreted from the N-glycosylation defective Cnalg3Δ mutant strain displayed a slightly increased adherence to the lung epithelial cells. Moreover, the N-glycan removed MP98(H) and MP88(H) were shown to be highly adhesive to the lung epithelial cells and macrophages. The MP98(H) and MP88(H) proteins with truncated N-glycans also stimulated more efficiently several cytokine secretion of the dendritic cells compared to the WT-secreted MP(H)s. These results indicate that highly mannosylated N-glycans seems to hide O-glycans or specific parts of proteins, which might serve as a ligand or an epitope, recognized by receptors of mammalian cells.