THE ROLE OF CEREAL AND FUNGAL AMYLASES IN CEREAL FLOUR HYPERSENSITIVITY

To investigate the role of cereal alpha and beta-amylase in bakers' as thma, we have compared the IgE response of 30 wheat-flour-allergic ind ividuals to barley alpha and beta-amylases with that of fungal alpha-a mylase using radioallergosorbent test (RAST), RAST inhibition assays a nd Western blotting. RAST analysis showed 29 of the 30 subjects with i nhalant induced cereal allergy had positive IgE to cereal amylases, bu t only 16 were positive to fungal alpha-amylase. Regression analysis s howed an association between specific IgE to wheat-flour and to barley alpha-amylase (r = 0.70) and barley beta-amylase (r = 0.92) but a poo r association with fungal alpha-amylase (r = 0.34). RAST inhibition sh owed minimal crossreactivity between barley alpha or beta-amylase and barley and fungal alpha-amylase. Sodium dodecyl sulphate-polyacrylamid e gel electrophoresis (SDS-PAGE) and Western blotting showed that non- reduced barley alpha-amylase had a molecular weight of 54 kDa and barl ey beta-amylase a molecular weight of 64 kDa. Reduced fungal alpha-amy lase had a molecular weight of 54 kDa. Cereal alpha and beta-amylase a ppear to be important allergens in patients with allergy to flour.