The complement alternative activation pathway (AP) is a principal cause of tissue damage in human diseases and injury states. Therapeutic agents designed to inhibit harmful complement activity have begun to emerge in the clinical setting. The C3 convertases are the key enzymes of complement activation. Complement-related disease and injury can be traced both to inappropriate convertase assembly (e.g. autoimmunity), and to convertase regulator dysfunction (e.g. atypical HUS, age-related macular degeneration). The control of convertase assembly and regulation is the key to therapeutic strategies for prevention of complement-related damage. Our long-range goal is to design new approaches for the prevention or inhibition of harmful complement. Of the three complement activation pathways, the alternative pathway (AP) in particular has been implicated in numerous disease and injury states. This proposal is directed to the AP and specifically to properdin, a component unique to the AP convertases and whose functions are not yet fully understood. Recently we, and others, have employed animal model systems to demonstrate that properdin is a promising therapeutic target for the amelioration of AP-dependent pathogenesis. In order to understand the mechanistic basis of properdin function and to develop a properdin-based strategy for the therapeutic inhibition of AP- dependent complement activity, we propose the following SPECIFIC AIMS:
Specific Aim 1. Use in vitro model systems to characterize the contribution of properdin pattern recognition activity to C activation.
Specific Aim 2. Elucidate the role(s) of properdin in animal models of AP-dependent pathogenesis.
Specific Aim 3. Develop anti-properdin reagents for the therapeutic inhibition of pathologic AP-dependent C activity. We expect the results from this work to have the potential to be highly translational and to significantly impact therapeutic strategies aimed at controlling the complement alternative pathway.

Public Health Relevance

The complement proteins protect us from infectious microorganisms but under other circumstances they can cause severe and potentially life-threatening tissue damage. The proposed research will provide new strategies and tools for successful therapeutic intervention in such cases.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI051436-11
Application #
8554356
Study Section
Innate Immunity and Inflammation Study Section (III)
Program Officer
Nasseri, M Faraz
Project Start
2003-04-01
Project End
2017-08-31
Budget Start
2013-09-01
Budget End
2014-08-31
Support Year
11
Fiscal Year
2013
Total Cost
$288,488
Indirect Cost
$98,693
Name
Washington University
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
068552207
City
Saint Louis
State
MO
Country
United States
Zip Code
63130
Wu, Xiaobo; Hutson, Irina; Akk, Antonina M et al. (2018) Contribution of Adipose-Derived Factor D/Adipsin to Complement Alternative Pathway Activation: Lessons from Lipodystrophy. J Immunol 200:2786-2797
Triebwasser, Michael P; Wu, Xiaobo; Bertram, Paula et al. (2018) Timing and mechanism of conceptus demise in a complement regulatory membrane protein deficient mouse. Am J Reprod Immunol 80:e12997
Yan, Huimin; Zhou, Hui-Fang; Akk, Antonina et al. (2016) Neutrophil Proteases Promote Experimental Abdominal Aortic Aneurysm via Extracellular Trap Release and Plasmacytoid Dendritic Cell Activation. Arterioscler Thromb Vasc Biol 36:1660-1669
Akk, Antonina; Springer, Luke E; Pham, Christine T N (2016) Neutrophil Extracellular Traps Enhance Early Inflammatory Response in Sendai Virus-Induced Asthma Phenotype. Front Immunol 7:325
Hourcade, Dennis E; Akk, Antonina M; Mitchell, Lynne M et al. (2016) Anti-complement activity of the Ixodes scapularis salivary protein Salp20. Mol Immunol 69:62-9
Renner, Brandon; Tong, Hua Hua; Laskowski, Jennifer et al. (2016) Annexin A2 Enhances Complement Activation by Inhibiting Factor H. J Immunol 196:1355-65
Bertram, Paula; Akk, Antonina M; Zhou, Hui-fang et al. (2015) Anti-mouse properdin TSR 5/6 monoclonal antibodies block complement alternative pathway-dependent pathogenesis. Monoclon Antib Immunodiagn Immunother 34:1-6
Yan, Huimin; Zhou, Hui-Fang; Hu, Ying et al. (2015) Suppression of experimental arthritis through AMP-activated protein kinase activation and autophagy modulation. J Rheum Dis Treat 1:5
Java, Anuja; Liszewski, M Kathryn; Hourcade, Dennis E et al. (2015) Role of complement receptor 1 (CR1; CD35) on epithelial cells: A model for understanding complement-mediated damage in the kidney. Mol Immunol 67:584-95
Pham, Christine T N; Thomas, Dennis G; Beiser, Julia et al. (2014) Application of a hemolysis assay for analysis of complement activation by perfluorocarbon nanoparticles. Nanomedicine 10:651-60

Showing the most recent 10 out of 21 publications