All of the following are mediators of inflammation, except:

Inflammatory mediators are the substances that initiate and regulate inflammatory reactions. The most impoant mediators of acute inflammation are vasoactive amines, lipid products (prostaglandins and leukotrienes), cytokines (including chemokines), and products of complement activation. Myeloperoxidase (MPO) is an enzyme present in primary (or azurophilic) granules of the neutrophils and takes pa in formation of reactive oxygen species. In the presence of a halide such as Cl-, MPO conves H2O2 to HOCl. (Hypochlorous radical) is used during the process of respiratory burst.