Interleukin-10 (IL-10) causes suppression or down modulation of T cell, B cell, and antigen presenting cell (APC) functions. However, cellular IL-10 (cIL-10), derived from mammalian cells, also has immunostimulatory properties. Conversely, viral IL-10 (vIL-10), encoded by the BCRF I open reading frame of the Epstein Barr virus, is almost exclusively immunosuppressive. The structural and physiological basis for these key characteristics and differences have not been defined. The applicant's preliminary data now demonstrate that a defined structural change can convert vIL-10 to cIL-10-like activity, or cIL-10 to vIL-10-like activity, by interchanging a single amino acid between the viral and cellular ligands. This structural change correlates with IL-10 binding to the previously described IL-10R1 chain and may correlate with the function of a newly described IL-10R2 chain. The applicant hypothesizes that cIL-10 and vIL-10 differentially bind IL-10 receptors, activate second messenger pathways, and induce immunosuppressive or immunostimulatory responses. Dr. Bromberg also hypothesizes that IL-10R1 and IL-10R2 and/or their associated second messengers are differentially distributed on different cell types. He proposes that elucidation of these differences will increase understanding of how IL-10 regulates immunity and allow the manipulation of IL-10 responses for immunosuppressive therapy in transplantation.
The specific aims of the proposed research are: 1) Demonstrate the structural basis of the binding to and activation of the IL-10R complex by IL-10 ligand constructs. Binding and competition assays will be performed between various cIL-10 and vIL-10 constructs and IL-10R1 and IL-10R2 chains. Additional studies will assay second messenger pathways through Western blotting and electrophoretic mobility shift assays for JAK-STAT activation. 2) Demonstrate the immunologic activity of IL-10 constructs on T cell, B cell, and APC function. The differential distribution of IL-10R1 and IL-10R2 on T, B, and APC subsets will also be characterized. 3) Demonstrate the in vivo immunological activity of IL-10 constructs in a transplant model. Gene transfer of IL-10 constructs to cardiac allograft will be performed and the effect on graft survival and immune activation of T, B, and APC functions evaluated.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI044929-02
Application #
6349893
Study Section
Surgery, Anesthesiology and Trauma Study Section (SAT)
Program Officer
Prasad, Shiv A
Project Start
2000-02-01
Project End
2005-01-31
Budget Start
2001-02-01
Budget End
2002-01-31
Support Year
2
Fiscal Year
2001
Total Cost
$374,776
Indirect Cost
Name
Mount Sinai School of Medicine
Department
Internal Medicine/Medicine
Type
Schools of Medicine
DUNS #
114400633
City
New York
State
NY
Country
United States
Zip Code
10029
Lal, Girdhari; Nakayama, Yumi; Sethi, Apoorva et al. (2015) Interleukin-10 From Marginal Zone Precursor B-Cell Subset Is Required for Costimulatory Blockade-Induced Transplantation Tolerance. Transplantation 99:1817-28
Krüger, Bernd; Yin, Na; Zhang, Nan et al. (2010) Islet-expressed TLR2 and TLR4 sense injury and mediate early graft failure after transplantation. Eur J Immunol 40:2914-24
Zhang, Nan; Schröppel, Bernd; Lal, Girdhari et al. (2009) Regulatory T cells sequentially migrate from inflamed tissues to draining lymph nodes to suppress the alloimmune response. Immunity 30:458-69
Boros, P; Bromberg, J S (2006) New cellular and molecular immune pathways in ischemia/reperfusion injury. Am J Transplant 6:652-8
Ochando, Jordi C; Homma, Chiho; Yang, Yu et al. (2006) Alloantigen-presenting plasmacytoid dendritic cells mediate tolerance to vascularized grafts. Nat Immunol 7:652-62
Chen, Dongmei; Zhang, Nan; Fu, Shuang et al. (2006) CD4+ CD25+ regulatory T-cells inhibit the islet innate immune response and promote islet engraftment. Diabetes 55:1011-21
Ochando, Jordi C; Yopp, Adam C; Yang, Yu et al. (2005) Lymph node occupancy is required for the peripheral development of alloantigen-specific Foxp3+ regulatory T cells. J Immunol 174:6993-7005
Safadi, Rifaat; Alvarez, Carlos E; Ohta, Masayuki et al. (2005) Enhanced oral tolerance in transgenic mice with hepatocyte secretion of IL-10. J Immunol 175:3577-83
Ding, Y; Qin, L; Zamarin, D et al. (2001) Differential IL-10R1 expression plays a critical role in IL-10-mediated immune regulation. J Immunol 167:6884-92