Basidiospore allergen release: elution from intact spores

We sought to test the hypothesis that allergens are readily released by intact basidiospores in vitro and that different species release allergens in different patterns that are related to spore wall structure.

To assess basidiospore allergen releasability, basidiospore allergens were extracted from disrupted spores and eluted from intact spores, and the allergenic potency of the extracts and eluates was compared in Calvatia cyathiformis, Psilocybe cubensis, Lentinus edodes, and Pleurotus ostreatus.

There was a significant species difference; on the basis of dry weight, the yield of extract and eluates from P1. ostreatus greatly exceeded the yield from C. cyathiformis extract and eluates. As measured by RAST inhibition, the allergenic potency of P1. ostreatus and L. edodes spore eluates reached the potency of disrupted spore extract in less than 4 hours. Allergen potency of Ps. cubensis and C. cyathiformis eluate approached the potency of disrupted spore extract only after 8 and 24 hours. Allergen staining intensity in sodium dodecyl sulfate polyacrylamide gel electrophoresis IgE immunoblot correlated with RAST activity. C. cyathiformis and Ps. cubensis spores have thick walls, whereas P1. ostreatus and L. edodes spore walls are thin and hyaline (nonpigmented). Thus spore allergen release may relate to spore wall characteristics.

These studies indicate that intact basidiospores of all four species release allergens, but the release patterns differ by species, and these differences may be clinically significant.