Role of CD14 in Host Response to Infection

CD14 may be considered as the major receptor of lipopolysaccharide (LPS), the causative factor of Gramnegative shock. CD14 is expressed on the surface of myeloid cells and is present in the serum as a soluble isoform. In this review both forms of CD14 and their biological functions are discussed. Emphasis is placed upon their differential role in infections. Possibilities and problems of the CD14 blockade during infection in animal models are summarized. Blockade of cellular activation by anti-CD14 antibodies diminishes bacterial clearance, whereas bacterial clearance is enhanced in CD14 knock-out mice, which completely lack both soluble CD14 and membrane bound CD14. These data suggest that therapeutic strategies using CD14 blockade should take both soluble and membrane bound forms of CD14 into account.