Immunological Analyses of Birch Pollen Antigens, with Special Reference to the Allergenic Components

Abstract

Birch pollen contains some ten antigenic components, demonstrable with immunodiffusion methods. One or two of these antigens differ from the others by a remarkable resistance to heat and extreme pH. In addition, these thermostable antigens are responsible for the major allergenic activity of birch pollen extracts and are more readily extracted from birch pollen than the other antigens. The allergenic thermostable antigens of birch pollen have counterparts, particularly in the pollen of alder, but also to some extent in that of hazel and aspen, as well as in hazelnut.

Demonstration of Birch Pollen Allergen from Isolated Pollen Grains Using Immunofluorescence and a Single Radial Immunodiffusion Technique

“…Only one or two of these are allergcnically active [2]. These antigens have been found to occur as separate precipitinogens after heat treatment of a birch-pollen extract and in the allergen-active fractions obtained after gel filtration of the extracts [3].…”

“…Bei.in [2] has shown that birch pollen contains some 10-15 1 Presented in part at the 7th F.uropean Congress of Allergology, W. Berlin, September 1968.…”

“…The present knowledge of allergen immunochemistry can only partly explain why only some of the pollen antigens cause sensitization in humans. In pollen of birch and grasses the allergen molecules arc distinguished from other antigens by a pronounced resistance to heat or storage at low or high pH [1,2,14]. The allergenic antigen of birch pollen is also the most readily extractable of all the antigens [2 ].…”

Sensitivity of IgG-ELISA for Detecting Airborne Pollen Antigens of Betulaceae

“…An aqueous extract of birch pollen contains six allergens (by CRIE, crossed radioimmunoelectrophoresis), but only one fulfills the conditions of a major allergen; Bet Y I (antigen 23) (Belin 1972a, 19726, Viander et al 1979, Apold et al 1981, Vik et al 1982, Ipsen & Lowenstein 1983, Marsh et al 1986) is of 17 kD (PI 5.25, 5.5, 5.0), a thermostable, cytosolic protein consisting of 159 amino acids. Bet Y I has at least three isoforms, which probably constitute more than 90-95% of the total allergen content (Vik et al 1983, Vik & Elsayed 1986, Valenta et al 1991a, Jilek et al 1993.…”

Antibody Response in Rabbits Following Intranasal and Parenteral Administration of Birch Pollen

“…Although birch pollen contains at least 10-15 distinct antigens [2] only 1 or 2 of these are associated with the major allergenic activity. The question then arises whether the allergenic components are allergenic be cause they have certain characteristics which enable them to reach reaginproducing cells or because they have a special ability to stimulate poten tially reagin-producing cells to antibody formation.…”