Influenza is a yearly epidemic that causes up to 500,000 global deaths annually. Most patients die of respiratory failure from either a primary viral pneumonia or a secondary bacterial infection. Therefore, finding host factors that can limit the progression of lung injury may lead to novel therapies for this deadly disease. Our preliminary data demonstrate that syndecan-1, a cell surface proteoglycan, regulates lung inflammation and reduces morbidity and mortality in mice after infection. Moreover, our data indicate that syndecan-1 restricts lung injury after influenza infection by limiting apoptosis in the airway epithelium. Our findings also show that syndecan-1 activates AKT, a pro-survival signal that can inhibit apoptosis. The central hypothesis for our proposal is that syndecan-1 is a pro-survival signal that attenuates epithelial apoptosis after influenza infection to limit lung injury. We will evaluate the mechanisms by which syndecan-1 regulates various apoptotic pathways. Additionally, we will investigate whether syndecan-1 suppresses apoptosis via activation of AKT. Finally, we will identify novel syndecan-1 co- receptors that mediate its cytoprotective effect. These studies will provide a platform for novel therapeutics that can target the airway epithelium to limit lung injury after influenza infection. This work may also have broader implications on other infectious diseases (viral and non-viral) of the lungs.

Public Health Relevance

Influenza is a deadly infection that has the potential for a large global burden of disease. Indeed, the 2009 pandemic highlighted many of the current deficiencies in influenza treatment (e.g., delay in vaccine production, resistance to antiviral therapy, etc.). These studies will provide a platform for novel therapeutics that can target the airway epithelium to limit lung injury after influenza infection and may have broader implications on other inflammatory diseases (viral and non-viral) of the lungs.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Research Project (R01)
Project #
7R01HL120947-02
Application #
8812061
Study Section
Lung Injury, Repair, and Remodeling Study Section (LIRR)
Program Officer
Caler, Elisabet V
Project Start
2014-01-01
Project End
2017-12-31
Budget Start
2014-03-03
Budget End
2014-12-31
Support Year
2
Fiscal Year
2014
Total Cost
$418,858
Indirect Cost
$178,135
Name
Cedars-Sinai Medical Center
Department
Type
DUNS #
075307785
City
Los Angeles
State
CA
Country
United States
Zip Code
90048
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