Allescheria boydii and Aspergillus fumigatus Skin Test Antigens1

MAY, LEWIS K. (Woman's Medical College of Pennsylvania, Philadelphia), RALPH A. KNIGHT, AND H. WILLIAM HARRIS. Allescheria boydii and Aspergillus fumigatus skin test antigens. J. Bacteriol. 91:2155-2157. 1966.-Protein and polysaccharide fractions were extracted from culture filtrates of Allescheria boydii and Aspergillus fumigatus by the methods of Seibert and of Heidelberger, and injected intradermally into guinea pigs previously infected with these fungi. The diameter of erythema and induration was determined at 8, 24, and 48 hr. The protein and polysaccharide antigens yielded specific skin reactions in homologously infected guinea pigs. Erythema appeared at 8 hr with both the protein and polysaccharide antigens. At this time, the polysaccharide skin tests showed erythema and a central blanched wheal. A similar wheal was not observed with the protein. The erythema of the polysaccharide reaction began fading at 24 hr, whereas the protein reaction remained unchanged through 48 hr with both antigens. In guinea pigs, the area of erythema was more constant and thus easier to measure than was induration. Evidence for a high prevalence of subclinical human histoplasmosis and coccidioidomycosis resulted from epidemiological studies with the use of appropriate skin tests. The incidence of subclinical human infection with Aspergillus and Allescheria species is unknown, since antigens appropriate for epidemiological studies are not available. Palmer, Edwards, and Allfather (6) detected a geographic area, including parts of Kansas, Oklahoma, Texas, and Louisiana, in which nonspecific histoplasmin hypersensitivity was prevalent. They believed this to have resulted from subclinical infection with an urnknown organism antigenically related to Histoplasma capsulatum. Reports by Pepys et al. (7) and by Campbell and Clayton (2) on the clinical and immunological aspects of human pulmonary aspergillosis have generated interest in the possibility that this infection might be more prevalent than has been recognized heretofore. With the belief that skin test antigens derived from Aspergillus and Allescheria species might be useful in epidemiological studies, this investigation was designed to produce protein and polysaccharide antigens from these fungus strains and to evaluate the delayed hypersensitivity re' Presented at the Annual Meeting of the American Society for Microbiology, Washington, D.C., 3-7 May 1964. actions obtained by intradermal injections of these antigens in experimentally infected guinea