Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Biological Chemistry

Mechanism Found For Isocyanate-Induced Asthma

Glutathione mediates response to chemical used in polymer production

by Celia Henry Arnaud
February 9, 2015 | A version of this story appeared in Volume 93, Issue 6

[+]Enlarge
Credit: Adam Wisnewski
Lung tissue in mice exposed to glutathione-MDI conjugates has elevated mucus production (red stain) along the airway and inflammatory cells in the air spaces and underlying tissue.
Micrograph of lung tissue from mouse exposed to glutathione-MDI conjugates.
Credit: Adam Wisnewski
Lung tissue in mice exposed to glutathione-MDI conjugates has elevated mucus production (red stain) along the airway and inflammatory cells in the air spaces and underlying tissue.

Isocyanates, which are used in the production of polymers such as polyurethane, have been recognized as a trigger for occupational asthma since the 1950s. Decades later, the mechanisms by which isocyanates exert their effects remain unclear. Now, Adam V. Wisnewski, Jian Liu, and Christopher M. Colangelo of Yale University School of Medicine report that the allergic reactions triggered by methyl­ene diphenyl diisocyanate (MDI) might be mediated by glutathione, a tripeptide antioxidant found at high levels in airway fluid (Chem. Res. Toxicol. 2015, DOI: 10.1021/tx5005002). The researchers administered glutathione-MDI conjugates to mice and found that MDI is transferred to a particular lysine residue in albumin, probably via a transcarbamoylation reaction. The immune proteins released in MDI-induced asthma are characteristic of macrophages, whereas proteins produced in other types of asthma are typical of T cells. The researchers also identified proteins that were produced at lower levels, and others at higher levels, in response to MDI exposure. The protein concentration changes could serve as biomarkers for MDI exposure or MDI-induced asthma.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.