Surfactant protein D decreases pollen-induced IgE-dependent mast cell degranulation.

Published

Journal Article

Mast cells play a key role in allergy and asthma. They reside at the host-environment interface and are among the first cells to make contact with inhaled microorganisms and particulate antigens. Pulmonary surfactant proteins A and D (SP-A and SP-D) function in lung host defense by enhancing microbe phagocytosis and mediating other immune cell functions, but little is known about their effects on mast cells. We hypothesized that SP-A and/or SP-D modulate IgE-dependent mast cell functions. Pollen starch granules (PSG) extracted from Dactylis glomerata and coated with trinitrophenol (TNP) were used as a model of an inhaled organic particulate allergen. Our data revealed that SP-D inhibited by 50% the release of beta-hexosaminidase by peritoneal mast cells sensitized with IgE anti-TNP and stimulated with TNP-PSG. In contrast, SP-A had no effect. Furthermore, SP-D aggregated PSG in a dose-dependent manner, and this aggregation was mediated by SP-D's carbohydrate recognition domain. A single arm SP-D mutant (RrSP-Dser15,20) neither aggregated PSG nor inhibited degranulation, suggesting that multimerization of SP-D is required for maximal PSG aggregation and inhibition of PSG-induced mast cell degranulation. This study is the first to demonstrate that SP-D modulates IgE-mediated mast cell functions, which are important in asthma and allergic inflammation.

Full Text

Duke Authors

Cited Authors

  • Malherbe, DC; Erpenbeck, VJ; Abraham, SN; Crouch, EC; Hohlfeld, JM; Wright, JR

Published Date

  • November 2005

Published In

Volume / Issue

  • 289 / 5

Start / End Page

  • L856 - L866

PubMed ID

  • 15980037

Pubmed Central ID

  • 15980037

International Standard Serial Number (ISSN)

  • 1040-0605

Digital Object Identifier (DOI)

  • 10.1152/ajplung.00009.2005

Language

  • eng

Conference Location

  • United States