title: Hyaluronan deposition and co-localization with inflammatory cells and collagen in a murine model of fungal allergic asthma.
abstract: OBJECTIVE
  Allergic asthma is a chronic inflammatory disease of the airways characterized by excessive inflammation and remodeling of the extracellular matrix (ECM) and associated cells of the airway wall. Under inflammatory conditions, hyaluronan (HA), a major component of the ECM, undergoes dynamic changes, which may in turn affect the recruitment and activation of inflammatory cells leading to acute and chronic immunopathology of allergic asthma.
  
  
  METHODS
  In the present study, we measured the changes in HA levels generated at sites of inflammation, and examined its effect on inflammatory responses and collagen deposition in an Aspergillus fumigatus murine inhalational model of allergic asthma.
  
  
  RESULTS
  We found that HA levels are elevated in allergic animals and that the increase correlated with the influx of inflammatory cells 5 days after the second allergen challenge. This increase in HA levels appeared largely due to upregulation of hyaluronidase-1 (HYAL1) and hyaluronidase-2 (HYAL2). Furthermore, HA co-localizes with areas of new collagen synthesis and deposition.
  
  
  CONCLUSIONS
  Overall, our findings contribute to the growing literature that focuses on the components of ECM as inflammatory mediators rather than mere structural support products. The evidence of HA localization in fungal allergic asthma provides the impetus to study HA more closely with allergic leukocytes in murine models. Further studies examining HA's role in mediating cellular responses may help to develop targets for treatment in patients with severe asthma due to fungal sensitization.
authors: Department of Veterinary and Microbiological Sciences, North Dakota State University, Dept 7690, P.O. Box 6050, Fargo, ND, 58105, USA, sumit.ghosh@ndsu.edu.
authors: Sumit
authors: S
authors: Ghosh
authors: Amali E
authors: AE
authors: Samarasinghe
authors: Scott A
authors: SA
authors: Hoselton
authors: Glenn P
authors: GP
authors: Dorsam
authors: Jane M
authors: JM
authors: Schuh
mesh_terms: D000485:Allergens / Q000276:immunology; D000818:Animals; D001232:Aspergillus fumigatus / Q000276:immunology; D001249:Asthma / Q000097:blood / Q000276:immunology* / Q000473:pathology; D016535:Bronchial Hyperreactivity / Q000097:blood / Q000276:immunology / Q000473:pathology; D001992:Bronchoalveolar Lavage Fluid / Q000276:immunology; D003094:Collagen / Q000378:metabolism; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000276:immunology*; D006820:Hyaluronic Acid / Q000097:blood / Q000235:genetics / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood / Q000276:immunology; D008168:Lung / Q000187:drug effects / Q000276:immunology / Q000473:pathology; D008810:Mice, Inbred C57BL
chemical_list: D000485:Allergens; D007073:Immunoglobulin E; D006820:Hyaluronic Acid; D003094:Collagen