ALLERGIC INFLAMMATION. III. THE FINE STRUCTURE OF COLLAGEN FIBRILS AT SITES OF ANTIGEN-ANTIBODY INTERACTION IN ARTHUS-TYPE LESIONS.

The fine structure of collagen fibrils at sites of antigen-antibody interaction is described. Following injection of antigen (BSA or ferritin) into the center of the cornea of hyperimmune rabbits, an acidophilic ring of precipitate forms at the periphery of the cornea, where antigen and antibody interact in optimal proportions. The precipitate is soon removed by infiltrating polymorphs, but persists longer in leukopenic animals. Electron microscopic examination of the cornea showed no alteration of the collagen fibrils in the area of antigen-antibody precipitation or in the remaining cornea. Contrary to many claims there was no swelling, fragmentation, or disintegration of the fibrils and they had a normal periodicity. Polymorphs infiltrated the precipitates and phagocytosed the antigen-antibody complexes. There was some ultrastructural evidence that degradation of the complexes took place in the polymorphs.