ABSTRACT
The discovery of immunoglobulin E (IgE) in the late 1960s introduced a new tool in allergy diagnosis, and determinations of specific IgE to different allergens were developed soon thereafter. Parallel to the development of new methods to measure specific IgE, there has been a revolution in the field of allergen extracts. In the beginning, crude natural and nonstandardized extracts were used, although in time, the use of standardized extracts with a more precise content of allergenic components improved the diagnostic value of these determinations. The next quantum leap came with the use of purified proteins obtained from natural sources.
