Comparison of different extraction methods of Alternaria allergens.

Spore and mycelial allergens of two species of Alternaria (A. brassicicola and A. alternata) extracted under two different conditions were analyzed by radiorocket immunoelectrophoresis, crossed radioimmunoelectrophoresis, and Western blotting with a pool of sera from Alternaria-allergic patients. More allergens were extracted after disruption of the cells if protease inhibitors and a phenol-binding component were included in the homogenization buffer. However, the 31 kDa major allergen was extracted in about the same amount, either by incubation or by cell breakage of the cells. This 31 kDa allergen was present in higher concentration in the mycelium than in the spore. The difference between the two species studied is less than between spore and mycelium from the same species.