Papain-induced asthma--physiological and immunological features.

Increasing reports of respiratory disease associated with exposure to papain prompted clinical, physiological, and immunological studies of the supervisor of a meat tenderizer factory who developed asthma after long-term contact with papain dust. His symptoms were worse at work and better on weekends and vacations. Bronchial inhalation challenges produced both immediate and late asthma to papain but not to the other ingredients in the food product. Immunological studies revealed the presence of specific IgE antibodies by direct and passive transfer skin tests and the radioallergosorbent test, and specific precipitating antibodies by immunodiffusion tests. These findings are indicative of a dual type I and III hypersensitivity. Papain acting as an allergen in an occupational setting is a risk factor for eliciting asthma even in a nontropic individual.