The outlined proposal is designed as a training program that builds on prior experiences and ultimately leads to a career of independent research. Included in this program for the applicant is the introduction of new experimental techniques, investigation of a new area of basic science, and interaction with a new mentor. The research project will investigate an important aspect of the development of pulmonary fibrosis. Pulmonary fibrosis has been shown to occur in conjunction with depressed alveolar plasminogen activator activity. This impaired activity occurs from an imbalance between urokinase-type plasminogen activator (uPA) and its major inhibitor, plasminogen activator inhibitor-1 (PAI-1). Enhancing alveolar plasminogen activator activity through various means including targeted deletion of the PAI-1 gene or adenoviral-mediated gene transfer of the uPA cDNA results in decreased collagen accumulation following a fibrogenic insult. The mechanism by which enhanced alveolar plaminogen activator activity mitigates fibrosis is unknown. Insights into this mechanism may lead to new treatments. Of several possibilities, two mechanisms are most likely. The hypothesis of this proposal is that enhanced alveolar plasminogen activator activity may reduce fibrosis by removing the provisional fibrin matrix or by increased levels of matrix metalloproteinases (MMPs). To test this hypothesis, 3 models of enhanced alveolar plasminogen activator activity will be employed. These models include a PAI-1 deficient transgenic mouse, adenoviral-mediated gene transfer of the uPA cDNA to the alveolar space, and an inducible lung-specific uPA expressing transgenic mouse. In addition, to investigate the importance of fibrin in lung scarring, a fibrinogen deficient transgenic mouse will be employed. With these models, differences in fibrin accumulation and MMP activation in mice protected from fibrosis will be compared to susceptible controls. The opportunities provided by the training program will provide the foundation for career advancement and hopefully lead to new therapies for fibrotic lung diseases.

Agency
National Institute of Health (NIH)
Institute
National Heart, Lung, and Blood Institute (NHLBI)
Type
Clinical Investigator Award (CIA) (K08)
Project #
5K08HL004434-03
Application #
6526590
Study Section
Special Emphasis Panel (ZHL1-CSR-K (M1))
Program Officer
Colombini-Hatch, Sandra
Project Start
2000-08-20
Project End
2005-07-31
Budget Start
2002-08-01
Budget End
2003-07-31
Support Year
3
Fiscal Year
2002
Total Cost
$133,462
Indirect Cost
Name
University of Michigan Ann Arbor
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
791277940
City
Ann Arbor
State
MI
Country
United States
Zip Code
48109
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