Hypersensitivity to tobacco antigen.

A glycoprotein of molecular weight 18,000 was purified from saline extracts of cured tobacco leaves by ammonium sulfate fractionation, chromatography on Sephadex G-25 and continuous-flow preparative electrophoresis on polyacrylamide gel. Twelve of 31 volunteers (6/15 smokers and 6/16 nonsmokers) exhibited immediate cutaneous hypersensitivity (wheal and flare reactions) when injected intracutaneously with 2 mug of this material. Immunochemically similar material was demonstrated in, and purified from, cigarette smoke condensate and cigarette smoke. The concentration in cigarette smoke condensate ("tar") was determined to be 1.8-3.6 mg/g. Antigenically crossreactive material was also demonstrated in eggplants, green peppers, potatoes, and tomatoes, which, like tobacco, are members of the family Solanaceae.