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Immunological analyses of birch pollen antigens, with special reference to the allergenic components.

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.