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Immune Tolerance Kyeong Cheon Jung Department of Pathology Seoul National University College of Medicine.

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Presentation on theme: "Immune Tolerance Kyeong Cheon Jung Department of Pathology Seoul National University College of Medicine."— Presentation transcript:

1 Immune Tolerance Kyeong Cheon Jung Department of Pathology Seoul National University College of Medicine

2 Immune tolerance Unresponsiveness to an antigen that is induced by previous exposure to that antigen Self tolerance: The normal lack of the ability to produce an immunological response to autologous (self) antigens. Transplantation tolerance : the specific absence of a destructive immune response to a transplanted tissue in the absence of immunosuppression Abbas: Cellular and Molecular Immunology 7E

3 Self tolerance Central tolerance  Negative selection  Receptor editing  Generation of regulatory T cells Peripheral tolerance  Clonal anergy  Clonal deletion  Regulatory T cells  T-T interaction Abbas: Cellular and Molecular Immunology 7E

4 Thymocyte Development Nat Immunol. 2006;7:338-334

5 Central tolerance of T cells Regulaotry T cells

6 Negative selection: mTEC vs DCs Trends Immunol 2002, 23:364-371

7 AIRE (Autoimmune Regulator) A gene or its encoded protein, which functions to stimulate expression of peripheral tissue protein antigens in medullary thymic epithelial cells

8 AIRE & promiscuous gene expression Trends Immunol. 2002, 23:364-71

9 AIRE & central Tolerance Role of AIRE in self antigen presentation  Induction of promiscuous gene expression  Induction of antigen presentation Role of AIRE + mTEC  Clonal deletion  Treg induction Role of DC  Uptake & presentation of antigen from AIRE + mTEC  negative selection

10 Defect in AIRE gene autoimmune polyendocrinopathy- candidiasis- ectodermaldystrophy (APECED), autoimmune polyglandular syndrome type 1 (APS-1) AIRE knock-out mouse

11 Defect in central tolerance: Qualitative difference Nat Med 2000, 6:56-61 B6 SJL Thymus Brain EAE

12 Manifestation of APS-1

13 Clonal anergy: functional unresponsiveness Clonal deletion: cell death Active suppression by regulatory T cells T-T interaction Peripheral tolerance

14 T cell anergy in the absence of co- stimulatory signals

15 Costimulatory vs. inhibitory moleccules B7-2 (CD86) : CD28 B7-1 (CD80) : CD28 CD40 : CD40L (CD154) ICOSL : ICOS CD70 : CD27 OX40L (CD134L) : OX40 (CD134) 4-1BBL : 4-1BB B7-2 : CTLA-4 B7-1 : CTLA-4 PD-L1, PD-L2: PD-1 Costimulation (APC : T cell) Inhibition (APC : T cell)

16 Circ Res. 2008, 103:1220-1231

17 CTLA-4/B7 vs. CD28/B7 Interaction Immunity, 1997, 7: 445-450

18 Immune dysregulation in human subjects with heterozygous mutations in CTLA4 Science, 2014, 345: 1623-1627

19 Development of abatacept & belatacept J Allergy Clin Immunol 2008, 121:299

20 PD-1–PD-L pathway contributes directly to T cell dysfunction during chronic viral infection Nat Immunol 2007, 8:239

21 PD-L1 KO mice infected with chronic form of virus Nature 2006, 439:682-687

22 PD-1–PD-L pathway in peripheral tolerance Am J Transplant. 2012;12:2575-87

23 PD-1 signaling Immunol Rev 2010; 236:219-242

24 Autoimmunity vs. anti-cancer immunity Anti-CTLA-4: Ipilimumab Anti-PD-1: Pembrozumab http://melanomamissionary.blogspot.com

25 Adverse Events in Patients Receiving Anti–PD-L1 Antibody N Eng J Med 2012, 266:2455-2465

26 Vitiligo caused by anti-CTLA-4 antibody therapy http://www.ascopost.com/issues/october-15,-2013/how-to-recognize-and-manage-ipilimumab -induced-dermatologic-adverse-events.aspx

27 Activation induced cell death (AICD)

28 Regulatory T cells: Subsets nTregiTregTr1Th3 Phenotype CD25++-++ CD103-++-- GITR++++-? CTLA-4+++++++++ Foxp3++++-/+- Cytokine secretion IL-10+/-++++++ TGF-  +++++ Differentiation factors TGF- , RAIL-10, IFN-  TGF- , IL-4 Suppression mechanism In vitroDiverse Diverse IL-10, TGF-  TGF-  In vivoDiverse Diverse IL-10, TGF-  TGF-  Modidifed from J Leukoc Biol. 2006, 80:458-470 & J Immunol 2003, 171:6323-6327

29 Yan Xing, and Kristin A. Hogquist Cold Spring Harb Perspect Biol 2012;4:a006957 ©2012 by Cold Spring Harbor Laboratory Press Differential TCR signalling in negative selection and Treg cell differentiation

30 Basic mechanisms used by Treg cells Nat Rev Immunol. 2008, 8:523-532 *IDO, indoleamine 2,3-dioxygenase

31 Induction of iTreg by cytokines TCR stimulation + IL-2 + TGF-   iTreg Retinoic acid  TGF-  + IL-6  Th17  TGF-  + RA  Treg  CD103 + DC in gut: retinal dehydrogenase  RA  Treg (J Exp Med 2007, 204:1757-1764)

32 Treg deficientyFoxp3 Mutation Foxp3 mutation  In human: IPEX (Immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome)  Mouse: Scurfy mutant IL-2/IL-2R deficiency TGF  deficiency

33 Immune regulation by T-T interaction Idiotype-anti-idiotype network  TCR peptide presentation via MHC I or II molecules  Immune suppression by anti-idiotype T cells Ergotype-anti-ergotype network  CD25 or HSP60 peptide presentation by MHC class I or II molecules  Immune suppression by anti-ergotypic T cells

34 Induced tolerance Front Immunol. 2012;3:274

35 Arrest of DC maturation in semimature stage via MD-3 Ab treatment - in vitro surface molecules -

36 Arrest of DC maturation in semimature stage via MD-3 Ab treatment - in vitro cytokine secretion -

37 Prolongation of porcine islet xenograft survival in humanize mice via MD-3 treatment

38 Control Ab MD-3 H&EInsulinCD3CD68 D Lack of immune cell infiltration in islet xenograft of MD-3-treated group

39 Long-term survival of islet xenograft in Rhesus monkeys via combined therapy

40 Self tolerance Central tolerance  Negative selection  Receptor editing  Generation of regulatory T cells Peripheral tolerance  Clonal anergy  Clonal deletion  Regulatory T cells  T-T interaction Abbas: Cellular and Molecular Immunology 7E


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