THE ROLE OF CHEMICAL MEDIATORS IN THE INFLAMMATORY RESPONSE INDUCED BY FOREIGN BODIES: COMPARISON WITH THE SCHISTOSOME EGG GRANULOMA

Abstract

Both divinyl benzene copolymer (plastic) beads and schistosome eggs produce inflammatory reactions after intravenous deposition into the lung of a mouse. As reported previously, the schistosome egg granuloma is an immunologic reaction of the delayed hypersensitivity type; this inflammatory process is prevented by immunosuppressive measures, and characteristically demonstrates an anamnestic response. In contradistinction, the plastic bead granuloma appears to be characteristic of a foreign body reaction; it is unaffected by immunosuppressive measures and does not demonstrate an anamnestic response with repeated exposure. The data in this report suggest that the granuloma formation around plastic beads is a nonimmunologic reaction induced by chemical mediators of inflammation. This proposal is supported by the following findings: the plastic beads activate Hageman factor in normal human and mouse plasma; the plastic beads induce vascular permeability-enhancing activity as measured in guinea pig skin and kinin-like activity in normal human and mouse plasma that is dependent on Hageman factor; ellagic acid, an agent that activates Hageman factor in vivo and is reported to diminish kininogen by consumptive depletion, markedly depresses the plastic bead granuloma. These data are consistent with the idea that the plastic bead granuloma and perhaps other foreign body inflammatory reactions are in major part dependent on kinin formation.