Interactions between IgE and house dust extract as studied by the radioallergosorbent test (RAST)

Several components in house dust extract can bind IgE, these interactions are not all immunologically specific. Non-immune interactions may conceivably contribute to the biological effects of house dust extract, they are actually found to interfere with the assay of allergen-specific IgE, especially when the serum under investigation has a high IgE content. By modification of the incubation medium, non-immune interactions can to a large extent be prevented. The immunological interactions between IgE and components in house dust extract have been investigated using twenty extracts, both in inhibition-type assay and in direct insolubilization assay. D. pteronyssinus-related allergens were found to be present in almost all extracts, however, not all house dust specific IgE reacted with mite-related allergens. Whether standardization of house dust extract is at all feasible, and if so, worthwhile, remains to be seen. It is clear, however, that no single figure can represent a completely reliable measure for the biological potency of a house dust extract.