The role of inflammatory cells in the pathogenesis of amyloidosis.

In the presence of amyloid enhancing factor, a variety of inflammatory stimuli, many of them nonantigenic, trigger amyloid deposition in 48 hours. There is a striking correlation between the extent of splenic amyloid deposition and the severity of inflammation at the injection site of the various irritants. Sublethal irradiation results in a parallel effect on the local inflammatory response and the accompanying extent of amyloid deposition produced in the spleen. Evidence that a product of local acute inflammatory responses is related to the deposition of amyloid is also presented. It is proposed that this product is a protease derived from the infiltrating polymorphonuclear leukocytes.