醫(yī)學(xué)免疫學(xué)課件：調(diào)節(jié)性T細(xì)胞在1型糖尿病治療中的應(yīng)用

1、調(diào)節(jié)性T細(xì)胞在1型糖尿病治療中的應(yīng)用Application of Regulatory T cells in Treatment of Type 1 Diabetes MellitusPart 1:Regulatory T cells1-1Introduction 調(diào)節(jié)性T細(xì)胞(regulatory T cell, Treg)，指能抑制其他免疫細(xì)胞活化、增殖的一種T細(xì)胞亞群，在維持自身穩(wěn)定、防止自身免疫性疾病、抑制排異反應(yīng)的發(fā)生中發(fā)揮重要作用，并參與腫瘤的免疫逃逸。https:/1-2Classification按來源不同：胸腺 - 自然發(fā)生調(diào)節(jié)性T細(xì)胞 (naturally occurrin

2、g Treg, nTreg)外周 - 誘導(dǎo)性調(diào)節(jié)性T細(xì)胞 (induced regulatory T cells, iTreg)按細(xì)胞表面標(biāo)志：CD4調(diào)節(jié)性T細(xì)胞 CD4+CD25+Foxp3+ 510% of CD4+ T cellsCD8調(diào)節(jié)性T細(xì)胞雙陰性T細(xì)胞1-3Molecular characterizationCD25：Sakaguchi等首次提出將CD25分子可作為Treg細(xì)胞的表面標(biāo)志（1995年）Foxp3：轉(zhuǎn)錄因子forkhead box P3(Foxp3)可作為Treg細(xì)胞的細(xì)胞內(nèi)標(biāo)志（2003年）DNA methylation analysis：foxp3基因上特定結(jié)構(gòu)

3、域發(fā)生DNA低甲基化（2013年）Ohkura N, Kitagawa Y, Sakaguchi S. Development and maintenance of regulatory T cellsJ. Immunity, 2013, 38(3): 414-423.T Cell Subpopulations Delineated by CD25, Foxp3, and the Treg-Cell-Type EpigenomeOhkura N, Kitagawa Y, Sakaguchi S. Development and maintenance of regulatory T cells

4、J. Immunity, 2013, 38(3): 414-423.A Model for Treg Cell Development in the ThymusGoldilocksOhkura N, Kitagawa Y, Sakaguchi S. Development and maintenance of regulatory T cellsJ. Immunity, 2013, 38(3): 414-423.Figure 1. Functional Significance of Treg-Cell-Type Epigenetic ChangesHOPE A S F O F. Foxp3

5、: Important regulatory gene for the development of regulatory T-cellsJOther Treg markers：CD3, neuropilin-1, CD103, GPR83, GITR, CTLA4.Sakaguchi S, Yamaguchi T, Nomura T, et al. Regulatory T cells and immune toleranceJ. Cell, 2008, 133(5): 775-787.Differentiation of Naive CD4+ T Cells into Tregs or E

6、ffector T Cells1-4DevelopmentSakaguchi S, Yamaguchi T, Nomura T, et al. Regulatory T cells and immune toleranceJ. Cell, 2008, 133(5): 775-787./2007/02/yxmyx/kc/kcnr/Word/yxmyx/images/image075.jpgCampbell D J, Koch M A. Phenotypical and functional specialization of FOXP3+ regulatory T cellsJ. Nature

7、Reviews Immunology, 2011, 11(2): 119-130.Figure 1. Functional differentiation of TReg cells and TH cells.1-5FunctionTreg細(xì)胞功能特征免疫無能性：對(duì)IL-2、APC、抗原的刺激呈低反應(yīng)狀態(tài)免疫抑制性：高濃度IL-2存在下，通過TCR刺激，可活化增殖，抑制CD4+和CD8+細(xì)胞的活化增殖Sakaguchi S, Yamaguchi T, Nomura T, et al. Regulatory T cells and immune toleranceJ. Cell, 2008, 1

8、33(5): 775-787.Key Roles of IL-2 in Immune HomeostasisMarekTrzonkowska N, Myliwec M, Siebert J, et al. Clinical application of regulatory T cells in type 1 diabetesJ. Pediatric diabetes, 2013, 14(5): 322-332.Treg細(xì)胞作用方式通過分泌抑制性細(xì)胞因子發(fā)揮免疫調(diào)節(jié)作用通過細(xì)胞間直接接觸發(fā)揮作用1-6Tregs and diseases自身免疫性疾病 Tregs發(fā)揮免疫抑制作用，維持機(jī)體自身免

9、疫耐受，防止自身免疫病的發(fā)生。慢性感染性疾病 病毒持續(xù)低水平感染時(shí)，Tregs調(diào)控病原體誘導(dǎo)的有效T細(xì)胞應(yīng)答與導(dǎo)致嚴(yán)重炎癥及組織破壞的過度T細(xì)胞反應(yīng)之間的平衡，即“抗感染免疫與免疫病理損傷的平衡”。炎癥性腸病 Tregs能夠維持腸道免疫穩(wěn)態(tài)，功能紊亂時(shí)可能導(dǎo)致腸道黏膜免疫系統(tǒng)對(duì)腸道非致病抗原的異常反應(yīng)發(fā)生炎癥。腫瘤 Tregs在腫瘤的免疫逃逸中發(fā)揮重要，抑制抗腫瘤T細(xì)胞的免疫應(yīng)答。Sakaguchi S, Yamaguchi T, Nomura T, et al. Regulatory T cells and immune toleranceJ. Cell, 2008, 133(5): 775

10、-787.器官移植免疫耐受IPEX Syndrome (Immunodysregulation Polyendocrinopathy Enteropathy X-linked syndrome) (Foxp3 mutation)：發(fā)生在小于六個(gè)月男嬰身上，出現(xiàn)脫落性皮炎，嚴(yán)重性水瀉和1型糖尿病等臨床癥狀 Ethan Shevach and Todd Davidson. January 2010 Vol 10 No 1. Produced with support from STEMCELL TechnologiesRegulatory T cellsPart 2:Diabetes mellit

11、us type 12-1Introduction Diabetes mellitus type 1 (DM1), is a form of diabetes mellitus that results from the autoimmune destruction of the insulin-producing beta cells in the pancreassubsequent lack of insulin increased blood and urine glucoseclassical symptoms including polyuria (frequent urinatio

12、n), polydipsia (increased thirst), polyphagia (increased hunger), weight loss/wiki/File:Main_symptoms_of_diabetes.pngFigure 1. Main Symptoms of Diabetes2-2PathophysiologyAn autoimmune response towards beta cells:an expansion of autoreactive CD4+ T helper cells and CD8+ T cellsautoantibody-producing

13、B cellsactivation of the innate immune systemdecrease of Treg ?2-3Prevention & ManagementImmunosuppressive drugsInsulin therapyPancreas transplantationIslet cell transplantationInduce Tregs in DM1 patients ?Part 3:Tregs in Treatment of DM13-1Views on Tregs in DM1(1) number and function of Tregs decr

14、eased in DM1 patients(2) extensively activated autoreactive T cells resistant to physiologically acting TregsFigure 1. In T1D subjects, Tregs isolated from CD4+ T cells have reduced function and increased apoptosis.Jailwala P, Waukau J, Glisic S, et al. Apoptosis of CD4+ CD25 high T cells in type 1

15、diabetes may be partially mediated by IL-2 deprivationJ. 2009.Figure 2. Model of tuned suppression: an immune response primes the regulation required for its safe resolutionWalker L S K. Regulatory T cells overturned: the effectors fight backJ. Immunology, 2009, 126(4): 466-474.tuned suppression3-2D

16、ifficultiesSafety(1) DM1 is not associated with imminent death(2) affects mainly the most vulnearby patients - childrenDifficulties of Treg cell treatment(1) complex phenotype of Treg cells(2) low percentage of Tregs in the periphery(3) loss of activity during ex vivo expansion3-3Animal ExperimentsT

17、regs can prevent destruction of pancreatic islets and fully protect from the development of autoimmune diabetesShortagesrelative doses of Tregs are higherfellow up only few weeksthe time of administration after Treg isolation is shorter3-4Approaches to induce Tregs in DM1 patientsOral insulin admini

18、strationanti-CD3 antibody treatmentPhase I - antibody binds to CD3 and induces apoptosis of activated T cellsPhase II - increase iTregs and iTregs produce IL-10 and TGF-autoantigen-based vaccine treatmentGAD-alumDiaPep277Vitamin D3 treatmentIsolation and ex vivo expansion of nTregs for clinical admi

19、nistrationFigure 1. Therapy with natural regulatory T cells(nTregs): outline of the procedureMarekTrzonkowska N, Myliwec M, Siebert J, et al. Clinical application of regulatory T cells in type 1 diabetesJ. Pediatric diabetes, 2013, 14(5): 322-332.3-5Clinical ImmunologyThe release criteria for the fi

20、nal Tregs product1) FoxP3 expression above 90% 2) passed IFN suppression assay3) negative microbiological testsmeasuring items:(1) metabolic responses: fasting C-peptide, glucagon, fasting glucose, HbA1c(2) immune responses: immunization response to hepatitis B, rubella viruses(3) FoxP3+CD4+CD3+ Tre

21、gs Figure 1. C-peptide, daily doses of insulin, HbA1C and fasting glucose in studied groupsFigure 1. Correlation between % of Tregs and serum C-peptide levelMarek-Trzonkowska N, Myliwiec M, Dobyszuk A, et al. Therapy of type 1 diabetes with CD4+ CD25 high CD127-regulatory T cells prolongs survival o

22、f pancreatic isletsResults of one year follow-upJ. Clinical Immunology, 2014, 153(1): 23-30.Figure 1. Correlatiion between % of Tregs and daily insulin dose (DID).Marek-Trzonkowska N, Myliwiec M, Dobyszuk A, et al. Therapy of type 1 diabetes with CD4+ CD25 high CD127-regulatory T cells prolongs surv

23、ival of pancreatic isletsResults of one year follow-upJ. Clinical Immunology, 2014, 153(1): 23-30.3-6Perspectives Success of Treg cells in treatment of Type 1 Diabetes MellitusFurther improvementtherapeutic effect of Tregs wanes with timeconfirm safety and efficacyReferencesSakaguchi, S., et al. (20

24、08). Regulatory T cells and immune tolerance. Cell 133(5): 775-787.Ohkura, N., et al. (2013). Development and maintenance of regulatory T cells. Immunity 38(3): 414-423.Brode, S., et al. (2006). Cyclophosphamide-Induced Type-1 Diabetes in the NOD Mouse Is Associated with a Reduction of CD4+CD25+Foxp3+ Regulatory T Ce