Waern, Ida
- Institutionen för husdjurens biovetenskaper, Sveriges lantbruksuniversitet
Konferensabstrakt2010Vetenskapligt granskadÖppen tillgång
Waern, Ida; Lundequist, Anders; Pejler, Gunnar; Wernersson, Sara
Mast cells release substantial amounts of active proteases, including chymase, upon activation and degranulation inresponse to e.g. IgE cross-linking. A chymase polymorphism has been associated with allergic asthma but the role of chymase in the pathogenesis is not fully understood. We recently showed that mouse mast cell protease 4 (mMCP-4) is the major chymotryptic enzyme in murine airways and that mMCP-4 can protect against bronchial hyperresponsiveness. We here assessed the role of chymase in a model of airway inflammation where mMCP-4 deficient (mMCP-4-/-) and wild type (WT) controls received repeated intranasal instillations of house dust mite (HDM). HDM-sensitization resulted in an accumulation of eosinophils and lymphocytes in the airways of both WT and mMCP-4-/- mice, but the numbers of eosinophils were approximately 5-fold higher in mMCP-4-/- mice. The airway inflammation correlated with the degree of T cell activation in draining lymph nodes. Moreover, the serum level of IgE was significantly higher in sensitized mMCP-4-/- mice than in WT mice. These results suggest a regulatory role for mMCP-4 in the early sensitization process when release of MC proteases in response to IgE cross-linking would be minimal. However, we found that HDM extract per se induced a low but significant degranulation in cultured MCs derived from both mMCP-4-/- and WT mice. Together these results suggest that MC chymase is released upon HDM exposure and that chymase has a protective role in HDM-induced airway inflammation by acting as a negative regulator of allergic sensitization.
International Immunology
2010, Volym: 22, nummer: Suppl 1 Pt 1, sidor: i134 Utgivare: Oxford University Press
Immunologi
Immunologi inom det medicinska området
Medicinsk biovetenskap
DOI: https://doi.org/10.1093/intimm/dxq107
https://res.slu.se/id/publ/50270