[Regulatory effects of proteases in articular inflammation]

The role of proteases in the stimulation of cells participating in a chronic inflammatory reaction is reviewed. Several neutral proteases stimulate B lymphocytes to produce both specific and unspecific antibodies and such enzymes can replace, at least in vitro, T-helper cells. Proteases might influence macrophages as well, by a MIF-like activity, by increasing spreading in vitro or by liberating from C3 the C3b component which has an activating effect on these cells. Endocytosis of protease - alpha-2 macroglobulin complexes by macrophages induces production of neutral proteases as well. A stimulation of fibroblasts by proteases is possible but not yet clearly proven.