Short-term sensitizing antibodies in bakers' asthma.

In a prospective study the occurrence of rye-specific IgG4 was investigated. We compared 17 bakers with clinical symptoms of bakers' asthma and a more than 100% increase in specific airway resistance following rye dust provocation to 16 bakers who showed neither symptoms of asthma nor an increase in specific airway resistance following rye dust provocation. In the group of patients with allergic type I responses, specific IgG4 was found in 15 cases by an indirect immunofluorescent test on rye grains. In none of the asymptomatic bakers was rye-specific IgG4 detected. In 15 symptomatic subjects rye-specific IgE alone or together with rye-specific IgG4 was found. In 2 cases only rye-specific IgG4--the so-called short-term sensitizing antibody--was demonstrated to explain the allergic bronchial response.