Collectins, col-lectins, (collagen-containing C-type lectins) are a part of the innate immune system.
Other functions of collectins are modulation of inflammatory, allergic responses, adaptive immune system and clearance of apoptotic cells.
There is a specific interaction between collectins and receptors on phagocytic cells which can lead to increased clearance of microorganisms.
This interaction causes decrease of TNF-α (tumor necrosis factor-α) production by alveolar macrophages stimulated with peptidoglycan.
They modulate the production of oxygen and nitrogen reactive species which are very important for phagocytic cells.
This interaction leads to inhibition of ligand-induced inflammatory by macrophage chemokine production.
[27][28][29] Collectins SP-A and SP-D enhance clearance of apoptotic cells by macrophages.