October 10, 2014

Aspirin and allergies

Drugs such as aspirin and indomethacin may increase sensitivity to airborne allergens by suppressing production of the signaling molecule PGI2, which in turn may offer a new treatment for allergies.

by Hannah Hankins

(iStock)

Asthma and other allergic diseases affect 40 million to 50 million Americans. Over the last few decades, cases of allergic diseases have risen sharply, and there is evidence that drugs that inhibit the enzyme cyclooxygenase (COX), such as aspirin and indomethacin, may contribute to this rise.

Reporting in the September issue of The Journal of Allergy and Clinical Immunology, Weisong Zhou, Ph.D., and colleagues describe in a mouse model the mechanism by which COX inhibition reduces immune tolerance – the suppression of immune responses – to aerosolized allergens.

The researchers showed that increased immune responsiveness (reduced tolerance) was due to suppression of COX-dependent prostaglandin I2 (PGI2) signaling, and that immune tolerance in COX-inhibited mice could be restored by treating the mice with a PGI2analog, a similar chemical compound.

These findings suggest that frequent use of COX-inhibiting drugs in humans may increase immune sensitivity to airborne allergens. They also highlight the potential clinical use of PGI2 analogs for allergy treatment.

The research was supported in part by National Institutes of Health grants AI111820, BX000624, AI095227, HL090664 and AI07641.

Send suggestions for articles to highlight in Aliquots and any other feedback about the column to aliquots@vanderbilt.edu