How Do Collectins Modulate the Function of Host Defense Cells?
Virtually nothing is now known about the mechanisms by which lung collectins directly modulate the function of host defense cells. In future studies it will be important to more systematically examine the effects of pre-incubating phagocytes with collectins (and washing) prior to exposure to microorganisms or other target particles. Further definition of the relevant receptors and glycoconjugate binding sites, and their associated mechanisms of signal transduction, should prove to be a fruitful area of investigation. Are There Acquired Deficiency States of Lung Collectins? Acute lung injuries of various types could theoretically lead to collectin inactivation as a consequence of protein modification (e.g., oxidation) or proteolytic degradation. Proteolytic cleavage at sites amino-terminal to the coiled-coil domain or disruption of intersubunit disulfide bonds could liberate trimeric carbohydrate binding fragments similar to RrSP-Dser15/20 or recombinant trimeric CRDs. Such molecules ar