ABSTRACT
The development of immunology and allergy in the beginning of the 20th century allowed identification of causative allergic factors, leading to a formal proposal of classification of intrinsic and extrinsic asthma syndromes by the American physician Rackeman in 1947 (12). Charles Harrison Blackley (18201900) (13) was the first physician to demonstrate that pollen allergy was the cause of seasonal hay fever by experimental pollen challenges carried out on himself. The beginning of the 20th century marked the discovery of anaphylaxis by the French scientists Charles Richet and Paul Portier. Von Pirquet and Bela Schick first coined the word “allergy” to describe severe reactions to horse serum, borrowing from Greek words (allos or “other” combined with ergon or “reaction”). Robert A. Cooke, an American physician who founded a famous clinic in New York, identified the hereditary component of allergy in 1916. Years 1909-1910 represented an important historic
milestone for asthma. Meltzer incriminated anaphylaxis in the pathogenesis of asthma (14,15), which in these years, was a major advance as the psychoneurotic was presumed on the basis of asthma including William Osler who wrote in his 1892 Principles and Practice of Medicine: “All writers agree that there is in a majority of cases of bronchial asthma a strong neurotic element”. This relationship between allergy and asthma was also supported by publications of Gilette, Debesche, as well as Biedl and Kraus in the same years. The Britton Leonard Noon prepared the first allergenic extracts used for desensitization in 1911. In the 1920s, Van Leeuwen from Utrecht described allergic reactions to human and pet danders as well as feathers and various molds. Blocking antibodies, later identified as IgGs, were described by Cooke in 1935 who also began the first allergen injection immunotherapy clinic in North America. Histamine is a major mediator of allergy, and the development of the first anti-histaminic preparations also took place in the beginning of the 20th century. The ability of the serum from allergic subjects to be passively transferred to the skin of a naive subject and elicit an immediate skin test reaction to an allergen (the PrausnitzKüstner test) was known as reaginic antibody (13). The passively transferred factor was referred to as “reaginic antibody” and was later found to be IgE immunoglobulins by Ishizaka and Ishizaka (16) in 1966-1967. Johansson (17) developed the radioallergosorbent test (RAST), a method widely used to measure serum-specific IgE for many food and airborne allergens. He also described high levels of IgE in asthma. The leukotrienes (formerly called slow-reactive substance of anaphylaxis) cascade was elucidated in the 1970s (13) and followed by major breakthroughs in understanding the role of specific subsets of lymphocytes in driving (Th2 cells) an regulating allergic inflammation (i.e., T-regulatory cells). The respective pathways of both innate and adaptive immune pathways have been defined for their roles in defending against infection or contributing to allergic disorders. Along with tremendous advances in molecular biology made in the past 50 years, the inflammatory component of asthma has been well characterized.
