Occupational Asthma Reference

Jones MG, Floyd A, Nouri-Aria KT, Jacobson MR, Durham SR, Taylor AN, Cullinan P, Is occupational asthma to diisocyanates a non-IgE-mediated disease?, J Allergy Clin Immunol, 2007;119:757-758,

Keywords: histology, IgE, isocyanate, challenge, mechanism

Known Authors

Paul Cullinan, Royal Brompton Hospital, London, UK Paul Cullinan

Tony Newman Taylor, Royal Brompton Hospital, London Tony Newman Taylor

Meinir Jones, Royal Brompton Hospital, London Meinir Jones

If you would like to become a known author and have your picture displayed along with your papers then please get in touch from the contact page. Known authors can choose to receive emails when their papers receive comments.


BACKGROUND: Exposure to diisocyanates in the workplace is an important cause of occupational asthma. The majority of patients with diisocyanate-induced asthma have no detectable diisocyanate-specific IgE antibodies in serum. There has been much debate as to whether this is due to diisocyanate-induced asthma being mediated by non-IgE mechanisms or whether it is the result of using inappropriate conjugates.

OBJECTIVE: We sought to determine whether RNA message for Cepsilon, IL-4, and other associated inflammatory markers could be detected locally within the bronchial mucosa after diisocyanate challenge.

METHODS: Fiberoptic bronchoscopic bronchial biopsy specimens were obtained at 24 hours after both a control and an active challenge in 5 patients with positive and 7 patients with negative inhalation test responses to diisocyanates. Using both immunohistochemistry and in situ hybridization, we determined mRNA for Cepsilon, IL-4, IL-5, and other associated inflammatory markers.

RESULTS: There was a striking absence of Cepsilon and IL-4 mRNA-positive cells in bronchial biopsy specimens from patients challenged with diisocyanate (Cepsilon median of 0 and interquartile range of 0-1.85; IL-4 median of 0 and interquartile range of 0-0.85). In contrast, there were increased numbers of IL-5-, CD25-, and CD4-positive cells and a trend toward an increase in eosinophils after active challenge with diisocyanate.

CONCLUSION: We found a striking absence of both bronchial Cepsilon and IL-4 RNA message after inhalation challenge with diisocyanates, irrespective of whether the challenge test response was positive or negative. We propose that diisocyanate-induced asthma is a non-IgE-mediated disease, at least in patients in whom specific IgE antibodies to diisocyanates are undetectable.

Full Text

Full text of this reference not available

Please Log In or Register to add the full text to this reference


Please sign in or register to add your thoughts.

Oasys and occupational asthma smoke logo