Effect of Mycobacterium tuberculosis chaperonins on bronchial eosinophilia and hyper-responsiveness in a murine model of allergic inflammation
Article first published online: 12 MAY 2004
Clinical & Experimental Allergy
Volume 34, Issue 5, pages 712–719, May 2004
How to Cite
Riffo-Vasquez, Y., Spina, D., Page, C., Tormay, P., Singh, M., Henderson, B. and Coates, A. (2004), Effect of Mycobacterium tuberculosis chaperonins on bronchial eosinophilia and hyper-responsiveness in a murine model of allergic inflammation. Clinical & Experimental Allergy, 34: 712–719. doi: 10.1111/j.1365-2222.2004.1931.x
- Issue published online: 12 MAY 2004
- Article first published online: 12 MAY 2004
- Submitted 24 March 2003; revised 6 November 2003; accepted 18 December 2003
- bronchial hyper-responsiveness;
Background Epidemiological evidence suggests that infection with Mycobacterium tuberculosis protects children against asthma. Several laboratories have shown that, in mouse models of allergic inflammation, administration of the whole live tuberculosis vaccine, Mycobacterium bovis bacillus Calmette–Guerin (BCG), prevents ovalbumin (OVA)-induced pulmonary eosinophilia.
Objective The aim of this study was to characterize specific M. tuberculosis molecules that are known to modulate immune responses to see if they affected pulmonary eosinophilia and bronchial hyper-responsiveness.
Methods C57Bl/6 mice were sensitized to OVA on days 0 and 7 and subsequently challenged with OVA on day 14 over a 3-day period. Pulmonary eosinophilia and bronchial hyper-responsiveness were measured 24 h following the last antigen challenge. In some groups, mice were pre-treated with M. tuberculosis or M. tuberculosis chaperonins (Cpns)60.1, 60.2 and 10, and the effect of this treatment on the allergic inflammatory response to aerosolized OVA was established.
Results We show that M. tuberculosis Cpns inhibit allergen-induced pulmonary eosinophilia in the mouse. Of the three Cpns produced by M. tuberculosis, Cpn60.1, Cpn10 and Cpn60.2, the first two are effective in preventing eosinophilia when administered by the intra-tracheal route. Furthermore, the increase in airways sensitivity to inhaled methacholine following OVA challenge of immunized mice was suppressed following treatment with Cpn60.1. The allergic inflammatory response was also characterized by an increase in Th2 cytokines IL-4 and IL-5 in bronchoalveolar lavage fluid, which was also suppressed following treatment with Cpn60.1.
Conclusion These data show that bacterial Cpns can suppress eosinophil recruitment and bronchial hyper-responsiveness in a murine model of allergic inflammation.