DC-SIGN, DC-SIGNR and LSECtin: C-type lectins for infection.

The C-type lectins DC-SIGN, DC-SIGNR and LSECtin are encoded by the lectin gene cluster on chromosome 19p13.3 and perform cell-adhesion and pathogen recognition functions on dendritic cells, liver cells and lymph node sinusoidal endothelial cells. DC-SIGN and DC-SIGNR share similar overall gene and protein molecule structures, and they exhibit high affinity for high-mannose carbohydrates. LSECtin, a Ca2+-dependent C-type lectin, interacts with mannose, NAcGlc and fucose. These lectins allow pathogen recognition (e.g., viruses, bacteria and allergens) and cell adhesion for dendritic and endothelial cells in different tissues, which may enhance the infection and facilitate the spread of those pathogens. A better understanding of these lectins may yield information about how pathogens are captured by particular cells and how they spread in different tissues. These studies would provide more detail about the physiopathological mechanisms of viral and bacterial infections and may also lead to new strategies to treat or prevent infections.