Heme oxygenase-1 (HO-1) protein induction in a mouse model of asthma
Article first published online: 20 DEC 2001
Clinical & Experimental Allergy
Volume 31, Issue 9, pages 1470–1477, September 2001
How to Cite
Kitada, O., Kodama, T., Kuribayashi, K., Ihaku, D., Fujita, M., Matsuyama, T. and Sugita, M. (2001), Heme oxygenase-1 (HO-1) protein induction in a mouse model of asthma. Clinical & Experimental Allergy, 31: 1470–1477. doi: 10.1046/j.1365-2222.2001.01179.x
- Issue published online: 20 DEC 2001
- Article first published online: 20 DEC 2001
- Submitted 28 April 2000; revised 5 December 2000; accepted 26 February 2000.
Background and objective Carbon monoxide (CO) is known to be present in measurable quantities in the exhalation of asthmatic patients. Corticosteroid treatment resulted in a decrease in exhaled CO levels in asthmatic patients, raising the possibility that an increase in exhaled CO concentration reflects inflammation of the asthmatic airway. Heme oxygenase-1 (HO-1) protein, also called HSP32, is the rate-limiting enzyme in the catabolism of heme to biliverdin, free iron and CO. However, it is unknown whether an expression of HO-1 within the lung tissue is related to allergic airway inflammation. We studied the expression of HO-1 in lung tissue and bronchoalveolar lavage cells in a mouse model of asthma.
Methods Ovalbumin (OVA)-sensitized C57BL/6 mice were challenged with aerosolized OVA. HO-1 positive cells were identified by immunostaining in lung tissue and bronchoalveolar lavage fluid (BALF) after the challenge.
Results HO-1 positive cell numbers increased in the subepithelium of the bronchi after OVA challenge. In cytospin preparations from BALF after OVA challenge, HO-1 was localized to alveolar macrophages. Inside the macrophages, HO-1 reactivity was expressed in the cytoplasm, and the perinuclear region in particular.
Conclusion The expression of HO-1 is increased within the lung tissue in allergic airway inflammation. Measurement of HO-1 activity may be clinically useful in the management of asthma.