Particulate and Soluble Antigens of Micropolyspora Faeni In Experimental Allergic Alveolitis of the Mouse

Publisher Website
Google Scholar
Abstract
Culture filtrates and total water-soluble extracts (TWSE), including ultrasonication products of M. faeni were primarily fractionated by electrophoresis in polyacrylamide gels. Other separations included chromatography with Con A[concanavalin A]-Sepharose and human immunoglobulins from sera that contained precipitins to farmer''s lung hay (FLH) antigen coupled to Sepharose 4B by the cyanogen-bromide method. Fractions were tested for their effects on the lung by the intranasal inoculation of non-immunized mice and of mice immunized with TWSE in Freund''s complete adjuvant to give precipitin-negative and precipitin-positive groups. Particulate antigens of M. faeni did not induce respiratory disease in non-immunized mice, but TWSE produced negligible, sporadic lesions. Precipitin-positive mice developed symptoms of extrinsic allergic alveolitis when challenged with particulate antigens consisting of living or dead spores and mycelium of M. faeni or with TWSE. Elements of type III (Arthus) and type IV (cell-mediated) hypersensitivities were identified histologically. The allergenicity of spores and mycelium was almost nullified by de-fatting, and activity was retained solely in a serologically inert ethanol-ether extract. Fractionation of soluble antigens produced immunologically-active extracts, only some of which induced clinical disease. Alveolitis-inducing glycoprotein antigens obtained from Con A-Sepharose by desorption with .alpha.-methyl-D-glucopyranoside precipitated in the C region on immunoelectrophoresis. A disease-provoking group of antigens precipitating in the A region was isolated by electrophoresis in agar after primary fractionation in polyacrylamide gel. Antigens desorbed both by 3.0 M acetic acid and 6.0 M guanidine-HCl from immunoadsorbent columns also precipitated in the A region, but only those desorbed by guanidine-HCl induced alveolitis. Most fractions inducing disease in precipitin-positive mice also did so in precipitin-negative, immunized animals. The formation of large hypersensitivity granulomata, indicative of the occurrence of a type IV cell-mediated response, followed the introduction of bentonite particles coated with reactive fractions into the lung. Mean diameters of the granulomata did not correlate directly with the degree of alveolitis induced by the fractions. Skin reactions were bimodal and showed early type III and late type IV histology.

This publication has 2 references indexed in Scilit: