The goal of this project is to identify and explore the molecular mechanisms of suppression of autoimmunity utilizing CD8+ Ti, CD4+CD25+ T regulatory cells with specific targeted genes differentially expressed by CD8+ inhibitory T cells (Ti) and CD4+ CD25+ T regulatory cells from tolerized mice compared to na?ve littermates in our murine model of SLE. Tolerization of young BWF1 mice with an artificial peptide that contains MHC Class I and Class II T cell determinants from Ig induces two sets of regulatory/inhibitory T cells that suppress autoantibody production. Genome scans of the first;pCONS-binding CD4+CD25+ Treg, show large numbers of genes upregulated and down regulated. The second, CD8+CD28- inhibitory T cells suppress autoantibody production in vitro- an effect that depends on secretion of TGF?1 and IFN? - and on adoptive transfer prevent disease in vivo. The number of genes upregulated or down regulated in those CD8+ Ti compared to CD8+CD28- T cells from unmanipulated littermates, is small. We chose 4 upregulated genes from CD8+Ti to study their role in suppressive function, which is directed against CD4+CD25- helper T cells. Upregulation of those genes in the CD8+Ti was identified by genome scan, and then confirmed by real-time PCR in multiple experiments. The 4 genes are Ifi202B, Trp53, bcl2 and Foxp3. Each gene is known to play a role in cell apoptosis, and each is influenced by levels of IFN and/or TGF?. Our strategy is to silence each of the 4 genes, alone or in combination, in CD8+ Ti, then measure the effect of that silencing on expression of Foxp3 and on cytokine production in the CD8+Ti cell itself and in its CD4+ helper T cell target. We will study the effects of silencing the genes of interest in vivo in adoptive transfer experiments. The overall purpose is to understand the molecular mechanisms by which these CD8+ inhibitory T cells and CD4+ T regulatory cells suppress autoimmunity;results may identify new targets for therapies for SLE in patients.

Agency
National Institute of Health (NIH)
Institute
National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS)
Type
Small Research Grants (R03)
Project #
5R03AR054034-03
Application #
7660510
Study Section
Special Emphasis Panel (ZAR1-EHB-H (J1))
Program Officer
Mancini, Marie
Project Start
2007-08-21
Project End
2011-07-31
Budget Start
2009-08-01
Budget End
2011-07-31
Support Year
3
Fiscal Year
2009
Total Cost
$75,460
Indirect Cost
Name
University of California Los Angeles
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Singh, Ram Pyare; Hasan, Sascha; Sharma, Sherven et al. (2014) Th17 cells in inflammation and autoimmunity. Autoimmun Rev 13:1174-81
Sawla, Priya; Hossain, Awlad; Hahn, Bevra H et al. (2012) Regulatory T cells in systemic lupus erythematosus (SLE); role of peptide tolerance. Autoimmun Rev 11:611-4
Singh, Ram P; Waldron, Richard T; Hahn, Bevra H (2012) Genes, tolerance and systemic autoimmunity. Autoimmun Rev 11:664-9
Dinesh, R; Hahn, B H; La Cava, A et al. (2011) Interferon-inducible gene 202b controls CD8(+) T cell-mediated suppression in anti-DNA Ig peptide-treated (NZB × NZW) F1 lupus mice. Genes Immun 12:360-9
Dinesh, Ravi K; Hahn, Bevra H; Singh, Ram Pyare (2010) PD-1, gender, and autoimmunity. Autoimmun Rev 9:583-7
Dinesh, Ravi K; Skaggs, Brian J; La Cava, Antonio et al. (2010) CD8+ Tregs in lupus, autoimmunity, and beyond. Autoimmun Rev 9:560-8
Singh, R P; Dinesh, R; Elashoff, D et al. (2010) Distinct gene signature revealed in white blood cells, CD4(+) and CD8(+) T cells in (NZBx NZW) F1 lupus mice after tolerization with anti-DNA Ig peptide. Genes Immun 11:294-309
Wong, Maida; La Cava, Antonio; Singh, Ram P et al. (2010) Blockade of programmed death-1 in young (New Zealand black x New Zealand white)F1 mice promotes the activity of suppressive CD8+ T cells that protect from lupus-like disease. J Immunol 185:6563-71
Lourenço, Elaine V; Procaccini, Claudio; Ferrera, Francesca et al. (2009) Modulation of p38 MAPK activity in regulatory T cells after tolerance with anti-DNA Ig peptide in (NZB x NZW)F1 lupus mice. J Immunol 182:7415-21
Singh, Ram Pyare; Hahn, Bevra H; La Cava, Antonio (2008) Tuning immune suppression in systemic autoimmunity with self-derived peptides. Inflamm Allergy Drug Targets 7:253-9

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