ABSTRACT
As with most biochemical disciplines, the history of allergen nomenclature dates back to the time when allergens were fractionated using a variety of “classical” biochemical separation techniques, and the active (most allergenic) fraction was usually named according to the whim of the investigator. Early attempts were made to purify pollen and house-dust allergens, using phenol extraction, salt precipitation, and electrophoretic techniques in the 1940-1950s. In the 1960s, ion exchange and gel filtration media were introduced and ragweed “antigen E” was the first allergen to be purified. This allergen was named by King and Norman because it was one of five precipitin lines (labeled A-E) that reacted rabbit polyclonal antibodies to ragweed in Ouchterlony immunodiffusion tests. Following purification, precipitin line E, or antigen E, was shown to be a potent allergen (1). Later, Marsh, working in Cambridge, England, isolated an important allergen from rye grass pollen (Lolium perenne) and used the name “Rye 1” to indicate that this was the first allergen purified from this species (2,3). In the 1970s, many allergens were purified from ragweed, rye grass, insect venoms, and other sources. The field was led by the laboratory of the late Dr. David Marsh, who had moved to the Johns Hopkins University, Baltimore, Maryland. At Hopkins, ragweed allergens, Ra3, Ra4, Ra5, and Ra6, and rye grass allergens, Rye 2 and Rye 3, were isolated and used for immunological and genetic studies of hay fever (4-6). At the same time, Ohman et al. identified the major cat allergen (Cat-I) (7) and Elsayed purified allergen M from codfish (8,9).
