CD209(redirected from CD209 antigen)
CD209A gene on chromosome 19p13 that encodes a pathogen-recognition receptor expressed on the surface of immature dendritic cells which is involved in initiating a primary immune response. These receptors are thought to recognise high mannose N-linked oligosaccharides present on the surface of pathogens (such as HIV-1, HIV-2 and SIV gp120, amongst others) in a calcium-dependent fashion. Once bound, the receptor mediates endocytosis of the pathogens, which are subsequently degraded in lysosomal compartments. The receptor returns to the cell membrane surface, while the pathogen-derived antigens are presented to resting T-cells via MHC class II proteins to initiate the adaptive immune response.
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