Published ahead of print on September 28, 2005, doi:10.1164/rccm.200503-361OC
© 2006 American Thoracic Society doi: 10.1164/rccm.200503-361OC
Inhibition of Spleen Tyrosine Kinase Prevents Mast Cell Activation and Airway HyperresponsivenessDivision of Cell Biology, Department of Pediatrics, National Jewish Medical and Research Center, Denver, Colorado; and Rigel Pharmaceuticals, Inc., San Francisco, California Correspondence and requests for reprints should be addressed to Erwin W. Gelfand, M.D., Department of Pediatrics, National Jewish Medical and Research Center, 1400 Jackson Street, Denver, CO 80206. E-mail: gelfande{at}njc.org Rationale: Spleen tyrosine kinase (Syk) is important for Fc and B-cell receptor–mediated signaling. Objective: To determine the activity of a specific Syk inhibitor (R406) on mast cell activation in vitro and on the development of allergen-induced airway hyperresponsiveness (AHR) and inflammation in vivo.
Methods: AHR and inflammation were induced after 10 d of allergen (ovalbumin [OVA]) exposure exclusively via the airways and in the absence of adjuvant. This approach was previously established to be IgE, Fc
Results: The inhibitor prevented OVA-induced degranulation of passively IgE-sensitized murine BMMCs and inhibited the production of interleukin (IL)-13, tumor necrosis factor Conclusion: This study delineates a functional role for Syk in the development of mast cell– and IgE-mediated AHR and airway inflammation, and these results indicate that inhibition of Syk may be a target in the treatment of allergic asthma.
Key Words: airway hyperresponsiveness • eosinophils • goblet cell metaplasia • mast cells • spleen tyrosine kinase This article has been cited by other articles:
|
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RI, and mast cell dependent. Alternatively, mice were passively sensitized with OVA-specific IgE, followed by limited airway challenge. In vitro, the inhibitor was added to cultures of IgE-sensitized bone marrow–derived mast cells (BMMCs) before cross-linking with allergen. 
, IL-2, and IL-6 in these sensitized BMMCs. When administered in vivo, R406 inhibited AHR, which developed in BALB/c mice exposed to aerosolized 1% OVA for 10 consecutive d (20 min/d), as well as pulmonary eosinophilia and goblet cell metaplasia. A similar inhibition of AHR was demonstrated in mice passively sensitized with OVA-specific IgE and exposed to limited airway challenge. 
