The ultimate goal--to radically improve graft survival without toxic side effects--must be achieved through induction of transplantation tolerance. However, tolerance induction requires initial deletion of donor-specific T and possibly B cell clones and subsequent generation of regulation to maintain tolerance. So far, no therapy induces controllable and selective deletion of donor-specific T and B cells without risking increased morbidity or mortality. Therefore, we will test two new families of apoptosis-indueing agents: 1) inducing single DNA breaks doxorubicin analogues a(nnamaycin; ANA, WP744, WP796, and WP853); and 2) selective Janus tyrosine kin ase (Jak)3 inhibitors (NC1153, WP938, WP988 and WP979). We already showed that WP744 induces apoptosis of only activated but not non-activated T cells; combination of WP744 with CD40Ligand (L) monoclonal antibody (mAb) induced tolerance to heart allografts. Similarly, NC 1153 alone induced T cell apoptosis resulting in tolerance to kidney allografts and in combination with CTL4-Ig to heart allografts. We will use unique models: T cells (but not B cells) from stimulators and activators of transcription (Stat)5a/b-deficient mice enter apoptosis after activation; whereas T cells from Stat4 and Stat6-deficient mice develop into interleukin (IL)-2-producing T helper (Th) 1 and IL-4-producing Th2, respectively; T cells from anti-apototic Bcl-2 gene over-expressing transgenic (Tg) mice display resistance to apoptosis. Using these mice we will examine the role of Stats in Bcl-2-dependent sensitivity or resistance to apoptosis in non-activated, activated and memory T cells following treatment with apoptosis-inducing agents. Apoptosis will be assessed by [a] visualization of karyolytic nuclear degeneration, [b] enzymatic detection of TdT-positive DNA degradation, [c] automated cytometric detection of annexin-V translocation, [d] expression of pro- versus antiapoptotic mRNAs in gene microarray/real-time PCR, and re] expression of Bcl-2 and Bcl-xL proteins by Western blot. In vivo, donor-specific T cell clones will be quantified by cytokine production by real-time PCR (IL-2, IL-4, IL10 and IFN-gamma) and RNase protection assay. Since T regulatory (Treg) cells are characterized as """"""""memory"""""""" T helper 2- type CD4+/CD25 + (Th2reg) cells, we plan to explore the IL-4/Stat6-regulated apotosis-resistance mechanism. The new agents may provide potent and save method for deletion of donor-specific lymphocytes for tolerance.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI061052-02
Application #
6913679
Study Section
Special Emphasis Panel (ZRG1-SAT (90))
Program Officer
Winter, David B
Project Start
2004-07-01
Project End
2009-06-30
Budget Start
2005-07-01
Budget End
2006-06-30
Support Year
2
Fiscal Year
2005
Total Cost
$270,325
Indirect Cost
Name
University of Texas Health Science Center Houston
Department
Surgery
Type
Schools of Medicine
DUNS #
800771594
City
Houston
State
TX
Country
United States
Zip Code
77225
Xie, Aini; Zheng, Xiong; Khattar, Mithun et al. (2015) TCR stimulation without co-stimulatory signals induces expression of ""tolerogenic"" genes in memory CD4 T cells but does not compromise cell proliferation. Mol Immunol 63:406-11
Khattar, Mithun; Deng, Ronghai; Kahan, Barry D et al. (2013) Novel sphingosine-1-phosphate receptor modulator KRP203 combined with locally delivered regulatory T cells induces permanent acceptance of pancreatic islet allografts. Transplantation 95:919-27
Miyahara, Y; Khattar, M; Schroder, P M et al. (2012) Anti-TCR? mAb induces long-term allograft survival by reducing antigen-reactive T cells and sparing regulatory T cells. Am J Transplant 12:1409-18
Wang, Guohua; Khattar, Mithun; Guo, Zhiyong et al. (2010) IL-2-deprivation and TGF-beta are two non-redundant suppressor mechanisms of CD4+CD25+ regulatory T cell which jointly restrain CD4+CD25- cell activation. Immunol Lett 132:61-8
Fernandes, Ida; Zhang, Ye; Qi, Yuhua et al. (2009) Impact of reduced nephron mass on cyclosporine- and/or sirolimus-induced nephrotoxicity. Transplantation 88:1323-31
Wenderfer, Scott E; Stepkowski, Stanislaw M; Braun, Michael C (2008) Increased survival and reduced renal injury in MRL/lpr mice treated with a novel sphingosine-1-phosphate receptor agonist. Kidney Int 74:1319-26
Zhang, Ye; Kirken, Robert A; Furian, Lucrezia et al. (2006) Allograft rejection requires STAT5a/b-regulated antiapoptotic activity in T cells but not B cells. J Immunol 176:128-37
Nagy, Zsuzsanna S; Rui, Hallgeir; Stepkowski, Stanislaw M et al. (2006) A preferential role for STAT5, not constitutively active STAT3, in promoting survival of a human lymphoid tumor. J Immunol 177:5032-40
Langer, Robert; Wang, Mouer; Stepkowski, Stanislaw M et al. (2004) Selectin inhibitor bimosiamose prolongs survival of kidney allografts by reduction in intragraft production of cytokines and chemokines. J Am Soc Nephrol 15:2893-901