Immunologic aspects of isocyanate asthma: IL-1 beta, IL-3, IL-4, sIL2R, and sICAM-1.

This pilot study investigated serum levels of cytokines and soluble receptors during five positive and five negative isocyanate inhalational challenges. Serum was obtained from 10 individuals with symptoms compatible with isocyanate asthma before isocyanate challenge and the day following their maximal change in pulmonary function after isocyanate challenge. Serum levels of interleukin 1 beta, interleukin 3, interleukin 4, soluble interleukin 2 receptor, and soluble intercellular adhesion molecule 1 were measured and compared. Interleukin 1 beta, interleukin 3, and interleukin 4 were not detected. The mean soluble interleukin 2 receptor and soluble intercellular adhesion molecule 1 levels were not statistically different before and after challenge or between groups. In summary, the cytokines studied are not detectable in peripheral blood during isocyanate inhalation challenge; soluble interleukin 2 receptor and soluble intercellular adhesion molecule 1 are both detectable but do not change significantly after a positive isocyanate challenge.