Articular cartilage is predominately composed of collagen and proteoglycan (PG) macromolecules. BALB/c mice immunized with human cartilage PG develop progressive polyarthritis. Clinical assessments and histopathologic studies of diarthrodial joints showed that these mice develop disease that is similar to human rheumatoid arthritis. In the progression to arthritis, autoantibodies and T cells develop that cross-react with both degraded and native mouse PG. Development of autoantibodies to PG directly correlates with the onset of disease. The autoreactive B cells, in addition to producing antibodies, are excellent presenters of PG epitopes for T cell recognition. Despite the inability of autoantibodies to transfer disease, autoantibodies synergize, with activated T cells, to promote the development of arthritis. However, the exact role of autoreactive B cells and autoantibodies in this disease remains unclear. Our overall hypothesis is that PG-specific autoantibodies are responsible for initiating the local inflammatory process in the joint through the recruitment of PG-specific lymphocytes, macrophages, and polymorphonuclear leukocytes. We know that circulating PG-specific autoantibodies gain access to the joint and that PGs are normally released from cartilage as a function of cartilage matrix turnover. Binding of the autoantibodies to PGs in the joint may be the first step in the cascade of events that leads to immune complex deposition and the initiation of inflammation. We hypothesize that binding of immune- complexes to Fc-gamma-Rs may act as an important stimulator of macrophages and synovial lining cells. These cells would then produce cytokines and chemokines that promote recruitment of leukocytes and subsequent inflammatory attack to cartilage and bone. Simultaneously these cytokines activate matrix metalloproteinases which further enhance the release of PG fragments into the joint space. In this study we will specifically address the mechanism by which B cells and autoantibodies induce the recruitment of leukocytes to the joint. Using several gene deficient mice, in aim 1 we will define the requirements for B cells and immunoglobulin in the development of PG-induced arthritis and determine whether circulating Ig is required for chemokine expression.
In aim 2 we will assess the involvement of Fc-gamma-Rs in induction of arthritis and whether Fc-gamma-Rs initiate chemokine mRNA expression in the joint.
In aim 3 we will define the requirements for specific chemokines in the systemic and local response to PG that induces arthritis.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Research Project (R01)
Project #
5R01AR047657-03
Application #
6744454
Study Section
General Medicine A Subcommittee 2 (GMA)
Program Officer
Gretz, Elizabeth
Project Start
2002-04-05
Project End
2007-03-31
Budget Start
2004-04-01
Budget End
2005-03-31
Support Year
3
Fiscal Year
2004
Total Cost
$305,406
Indirect Cost
Name
Rush University Medical Center
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
068610245
City
Chicago
State
IL
Country
United States
Zip Code
60612
Olalekan, Susan A; Cao, Yanxia; Hamel, Keith M et al. (2015) B cells expressing IFN-? suppress Treg-cell differentiation and promote autoimmune experimental arthritis. Eur J Immunol 45:988-98
Hamel, Keith M; Cao, Yanxia; Olalekan, Susan A et al. (2014) B cell-specific expression of inducible costimulator ligand is necessary for the induction of arthritis in mice. Arthritis Rheumatol 66:60-7
Finnegan, Alison; Ashaye, Susan; Hamel, Keith M (2012) B effector cells in rheumatoid arthritis and experimental arthritis. Autoimmunity 45:353-63
Hamel, Keith M; Cao, Yanxia; Ashaye, Susan et al. (2011) B cell depletion enhances T regulatory cell activity essential in the suppression of arthritis. J Immunol 187:4900-6
Glant, Tibor T; Radacs, Marianna; Nagyeri, Gyorgy et al. (2011) Proteoglycan-induced arthritis and recombinant human proteoglycan aggrecan G1 domain-induced arthritis in BALB/c mice resembling two subtypes of rheumatoid arthritis. Arthritis Rheum 63:1312-21
Hamel, Keith M; Cao, Yanxia; Wang, Yumei et al. (2010) B7-H1 expression on non-B and non-T cells promotes distinct effects on T- and B-cell responses in autoimmune arthritis. Eur J Immunol 40:3117-27
O'Neill, Shannon K; Veselits, Margaret L; Zhang, Miao et al. (2009) Endocytic sequestration of the B cell antigen receptor and toll-like receptor 9 in anergic cells. Proc Natl Acad Sci U S A 106:6262-7
Farkas, Balint; Boldizsar, Ferenc; Tarjanyi, Oktavia et al. (2009) BALB/c mice genetically susceptible to proteoglycan-induced arthritis and spondylitis show colony-dependent differences in disease penetrance. Arthritis Res Ther 11:R21
Hamel, Keith; Doodes, Paul; Cao, Yanxia et al. (2008) Suppression of proteoglycan-induced arthritis by anti-CD20 B Cell depletion therapy is mediated by reduction in autoantibodies and CD4+ T cell reactivity. J Immunol 180:4994-5003
O'Neill, Shannon K; Cao, Yanxia; Hamel, Keith M et al. (2007) Expression of CD80/86 on B cells is essential for autoreactive T cell activation and the development of arthritis. J Immunol 179:5109-16

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