張會(huì)寧 王嘉軍
[摘要] Th9細(xì)胞是CD4+T細(xì)胞新發(fā)現(xiàn)的分化細(xì)胞亞群,該細(xì)胞通過(guò)分泌白細(xì)胞介素-9(IL-9)參與機(jī)體的免疫應(yīng)答。在類風(fēng)濕關(guān)節(jié)炎、系統(tǒng)性紅斑狼瘡等自身免疫病患者血液和組織中Th9細(xì)胞比例和IL-9的含量會(huì)產(chǎn)生較大變化,表明其與自身免疫病的發(fā)生發(fā)展有著密切關(guān)系。本文就近幾年Th9細(xì)胞與常見自身免疫病相關(guān)性研究進(jìn)展進(jìn)行綜述。
[關(guān)鍵詞] Th9細(xì)胞;自身免疫病;類風(fēng)濕關(guān)節(jié)炎;系統(tǒng)性紅斑狼瘡;白細(xì)胞介素-9
[中圖分類號(hào)] R392.12 ? ? ? ? ?[文獻(xiàn)標(biāo)識(shí)碼] A ? ? ? ? ?[文章編號(hào)] 1673-7210(2019)10(a)-0048-04
Research progress on correlation between CD4+ new subsets of Th9 cells and common autoimmune diseases
ZHANG Huining1 ? WANG Jiajun2
1.Department of Nurse, An-Ning Sub-Hospital in 940th Hospital in Joint Logistic Support Force of the People′s Liberation Army of China, Gansu Province, Lanzhou ? 730070, China; 2.Teaching and Research Section of Medical Immunology, School of Medicine, Hubei Minzu University, Hubei Province, Enshi ? 445000, China
[Abstract] Th9 cells are a newly discovered subset of differentiated CD4+T cells that participate in the body′s immune response by secreting interleukin-9 (IL-9). In patients with autoimmune diseases such as rheumatoid arthritis and systemic lupus erythematosus, the proportion of Th9 cells and the content of IL-9 in the blood and tissues will change greatly, indicating that it is closely related to the occurrence and development of autoimmune diseases. This paper reviews the research progress on the correlation between Th9 cells and common autoimmune diseases in recent years.
[Key words] Th9 cells; Autoimmune disease; Rheumatoid arthritis; Systemic lupus erythematosus; Interleukin-9
初始CD4+T細(xì)胞在樹突狀細(xì)胞(dendritic cells,DC)提呈的雙信號(hào)及細(xì)胞因子的作用下活化、增殖,而細(xì)胞因子微環(huán)境的差異決定其同時(shí)分化為不同效應(yīng)的細(xì)胞亞群。CD4+T效應(yīng)性細(xì)胞亞群有分泌干擾素(IFN)、腫瘤壞死因子(TNF)等為主的Th1,輔助B細(xì)胞活化的Th2,分泌白細(xì)胞介素(IL)-17、23誘導(dǎo)炎性反應(yīng)的Th17,以及新近發(fā)現(xiàn)的Th9亞群。Th9細(xì)胞是IL-4和轉(zhuǎn)化生長(zhǎng)因子-β(TGF-β)共同誘導(dǎo)下激活的多種下游轉(zhuǎn)錄因子如富含嘌呤盒1(purine-rich box 1,PU.1)、干擾素調(diào)節(jié)因子4(interferon regulatory factor-4,IRF4)、轉(zhuǎn)錄信號(hào)轉(zhuǎn)導(dǎo)及活化因子6(signal transducer and activator of transcription-6,STAT6)后分化,分泌高濃度的IL-9作為主要效應(yīng)分子新亞群[1-2]。近年研究發(fā)現(xiàn),多種常見自身免疫病發(fā)生、發(fā)展及病情嚴(yán)重程度與Th9細(xì)胞密切相關(guān)[3]。現(xiàn)將Th9細(xì)胞的生物學(xué)特性及與自身免疫病相關(guān)性的研究進(jìn)展綜述如下:
1 Th9細(xì)胞概述
2008年,兩個(gè)研究組[4-5]均發(fā)現(xiàn)在TGF-β和IL-4共同作用小鼠初始CD4+T細(xì)胞后誘導(dǎo)分化為可分泌IL-9、IL-10等,但不表達(dá)Th1細(xì)胞T-bet、Th2的GATA-3、Treg的Foxp3和Th17的RORγt等轉(zhuǎn)錄因子,卻表達(dá)PU.1和IRF4等轉(zhuǎn)錄因子的T細(xì)胞亞群,這種T細(xì)胞亞群被命名為“Th9”細(xì)胞。2010年有學(xué)者在過(guò)敏患者的外周血中發(fā)現(xiàn)了Th9細(xì)胞[6],隨后在正常和炎性皮膚中也相繼檢測(cè)出Th9細(xì)胞[7]。
2 誘導(dǎo)及抑制Th9細(xì)胞分化的細(xì)胞因子
IL-4和TGF-β是誘導(dǎo)初始CD4+T細(xì)胞分化為Th9細(xì)胞的主要調(diào)節(jié)因子。其中TGF-β可單獨(dú)誘導(dǎo)Th2細(xì)胞轉(zhuǎn)化為Th9細(xì)胞。動(dòng)物實(shí)驗(yàn)顯示[8],TGF-β受體Ⅱ基因缺陷小鼠即使給予IL-4和TGF-β刺激,其初始CD4+T細(xì)胞仍無(wú)法分化為Th9細(xì)胞,提示完整的TGF-β受體是促使初始CD4+T細(xì)胞分化為Th9細(xì)胞的關(guān)鍵分子。而缺乏IL-4時(shí),IL-1α、IL-1β、IL-18和IL-33均可取代或替代IL-4的作用和TGF-β共同刺激誘導(dǎo)產(chǎn)生Th9細(xì)胞。IL-1β能促進(jìn)該細(xì)胞分泌高濃度的IL-9[9]。此外,動(dòng)物實(shí)驗(yàn)提示,IL-21或IL-21受體缺陷型小鼠CD4+T細(xì)胞較野生型小鼠更易分化為Th9細(xì)胞[10]。IL-21抑制Th9細(xì)胞合成分泌IL-9。
3 調(diào)控Th9細(xì)胞信號(hào)通路與轉(zhuǎn)錄因子
3.1 TGF-β途徑和PU.1
TGF-β信號(hào)誘導(dǎo)轉(zhuǎn)錄因子PU.1表達(dá),直接結(jié)合活化IL-9基因啟動(dòng)子,是Th9細(xì)胞分化的唯一特異性轉(zhuǎn)錄因子[11]。PU.1對(duì)人和鼠Th9細(xì)胞生成IL-9有重要的調(diào)控作用,如初始CD4+T細(xì)胞PU.1缺陷,則很難分化為Th9,同時(shí)分泌IL-9降低[12]。Th9細(xì)胞中PU.1表達(dá)顯著高于Th2細(xì)胞[13],表明PU.1促使向Th9細(xì)胞轉(zhuǎn)化。
3.2 IL-4途徑和IRF4
IL-4-STAT6途徑激活I(lǐng)RF4基因,IRF4可以與IL-9基因啟動(dòng)子結(jié)合進(jìn)而促進(jìn)IL-9表達(dá),促使初始CD4+T細(xì)胞向Th9細(xì)胞亞群分化[14]。敲除或siRNA阻斷IRF4表達(dá)的CD4+T胞則無(wú)法分化為Th9細(xì)胞[15]。盡管IRF4對(duì)Th9細(xì)胞的分化作用重大[16],但它也參與Th2和Th17細(xì)胞的分化,并非是Th9特異性的轉(zhuǎn)錄因子[17]。
3.3 Notch協(xié)同Smad途徑
Smad與Notch胞內(nèi)區(qū)域NICD1結(jié)合,在RBP-JK協(xié)同下與IL-9啟動(dòng)子結(jié)合后開始轉(zhuǎn)錄并表達(dá),從而誘導(dǎo)分化為Th9細(xì)胞,敲除Notch1和Notch2受體,Th9細(xì)胞分化明顯減弱[18]。
3.4 活化NF-κB的信號(hào)通路
OX40/OX40L和GITR/DTA-1信號(hào)通路:Th細(xì)胞上OX40(即CD134)與APC膜分子OX40L結(jié)合后[19]或初始CD4+T細(xì)胞的GITR與配體DTA-1結(jié)合后[20],均可通過(guò)激活TRAF6,向下激活NF-κB,啟動(dòng)IL-9表達(dá),誘導(dǎo)分化為Th9細(xì)胞。OX40/OX40L對(duì)IL-9表達(dá)具有選擇特異性,可抑制或沉默IL-4、IL-5等其他因子的表達(dá)[21]。
4 Th9細(xì)胞與自身免疫病
Th9細(xì)胞分泌IL-9,可促進(jìn)Th17細(xì)胞分泌促炎因子IL-17、IFN-γ、IL-1和TNF,共同介導(dǎo)炎性反應(yīng),協(xié)同促進(jìn)自身免疫病的發(fā)生、發(fā)展,參與這些疾病的病理過(guò)程。
4.1 類風(fēng)濕關(guān)節(jié)炎(rheumatoid arthritis,RA)
Ciccia等[22]發(fā)現(xiàn)RA患者IL-9及受體、IL-4及TGF-β水平在滑膜組織中都升高,認(rèn)為Th9可能參與了RA的發(fā)病機(jī)制。RA患者外周血單核細(xì)胞中Th9比例顯著高于對(duì)照組;中度活動(dòng)和高度活動(dòng)患者組Th9的表達(dá)率均高于對(duì)照組;且高度活動(dòng)患者組血清中IL-9的表達(dá)率顯著高于中度活動(dòng)組。IL-9表達(dá)的百分率與RA患者的紅細(xì)胞沉降率、關(guān)節(jié)壓痛數(shù)、關(guān)節(jié)腫脹數(shù)及類風(fēng)濕因子呈正相關(guān),這一結(jié)果提示Th9及IL-9參與RA的發(fā)病,且與病情程度有關(guān),但具體機(jī)制仍需進(jìn)一步研究[23]。
4.2 系統(tǒng)性紅斑狼瘡(systemic lupus erythematosus,SLE)
國(guó)外學(xué)者[24-25]發(fā)現(xiàn)狼瘡傾向MRL/lpr實(shí)驗(yàn)小鼠B細(xì)胞增殖和自身抗體、Th9細(xì)胞分化以及IL-9的表達(dá)有一定相關(guān)性,同時(shí)發(fā)現(xiàn)SLE小鼠脾臟Th9細(xì)胞數(shù)目、血清IL-9和抗雙鏈DNA抗體濃度均顯著高于正常小鼠,提出Th9細(xì)胞可能是SLE誘因之一。Ouyang等[26]檢測(cè)結(jié)果顯示,SLE患者血清中IL-9含量和外周血中單核細(xì)胞IL-9mRNA表達(dá)均顯著高于正常組,活動(dòng)期水平更高。SLE患者使用大劑量氫化考地松治療后,IL-9含量顯著降低,表明IL-9與SLE炎癥有關(guān)。另有研究顯示,褪黑素可有效抑制IL-9的表達(dá),有助于SLE治療[27]。由此推斷,阻斷IL-9表達(dá)是治療SLE潛在的有效靶點(diǎn)[28]。
4.3 潰瘍性結(jié)腸炎(ulcerative colitis,UC)
研究發(fā)現(xiàn)UC活檢組織中IL-9水平、IL-9mRNA顯著增高,增高水平與UC嚴(yán)重程度呈正相關(guān)[29-30]。IL-9可誘導(dǎo)腸上皮細(xì)胞分泌炎癥介質(zhì),抑制細(xì)胞增殖,改變腸道黏膜屏障的通透性,損傷屏障作用,阻止黏膜傷口愈合。有結(jié)果顯示,IL-9可造成腸道正常菌群紊亂、阻止?jié)冇?、增?qiáng)炎癥進(jìn)展[31]。此外,有研究報(bào)道,Th9細(xì)胞可誘導(dǎo)STAT6、IRF4和PU.1基因轉(zhuǎn)錄,且表達(dá)水平與UC炎癥呈正相關(guān)[32]。
4.4 銀屑?。≒soriasia)
動(dòng)物實(shí)驗(yàn)結(jié)果顯示,模型小鼠皮內(nèi)注射IL-9,不僅CD4+T轉(zhuǎn)化為Th17細(xì)胞增加,而且局部炎癥增強(qiáng),血管內(nèi)皮生長(zhǎng)因子(VEGF)和CD31分子表達(dá)增強(qiáng)。而注射抗IL-9抗體后,病變炎癥和血管增生減輕,既可延緩疾病發(fā)展,還能降低多種炎癥細(xì)胞造成的表皮增生和浸潤(rùn)[33]。注射抗IL-17抗體,小鼠炎癥細(xì)胞中IL-9 mRNA及血中IL-9含量降低,IL-9誘導(dǎo)的炎癥和表皮增生緩解。臨床資料顯示,患者皮損局部IL-9R表達(dá)顯著高于正常組,推斷可能是IL-9誘導(dǎo)病變局部炎癥及血管增生,進(jìn)一步加重患者皮膚損傷[34]。
4.5 實(shí)驗(yàn)性自身免疫重癥肌無(wú)力(experimental autoimmune myasthenia gravis,EAMG)
Yao等[35]在研究完全弗氏佐劑組(CFA組)和EAMG組兔子淋巴結(jié)中的單核細(xì)胞實(shí)驗(yàn)時(shí)發(fā)現(xiàn),早期時(shí),兩組中Th9細(xì)胞無(wú)顯著性差異。但晚期時(shí),EAMG組Th9細(xì)胞百分比較對(duì)照組明顯增高。提取單核巨噬細(xì)胞(M?拚)總RNA,實(shí)時(shí)定量PCR結(jié)果顯示,CFA組PU.1mRNA表達(dá)較EAMG組顯著降低。EAMG組病情發(fā)展以AchR表達(dá)顯著降低為特征,使用IL-9-Ab可有效抑制體液免疫應(yīng)答,降低抗乙酰膽堿受體抗體(AchR-Ab)的合成分泌,從而減少或阻斷抗AchR-Ab與特異性乙酰膽堿受體(AchR)結(jié)合,緩解EAMG癥狀,產(chǎn)生保護(hù)作用.
4.6 橋本甲狀腺炎(hashimoto thyroiditis,HT)
HT患者外周血中Th9細(xì)胞百分比、PU.1mRNA表達(dá)及IL-9含量均較對(duì)照組顯著升高,且與甲狀腺特異性自身抗體含量呈正相關(guān),提示Th9細(xì)胞可能與HT發(fā)生發(fā)展有關(guān)[36]。
4.7 實(shí)驗(yàn)性自身免疫性腦脊髓炎(experimental autoimmune cerebrospinal meningitis,EAE)
移植使用髓鞘少突膠質(zhì)糖蛋白35-55(MOG35-55)體外誘導(dǎo)分化的Th9細(xì)胞可過(guò)繼誘發(fā)受試小鼠表現(xiàn)EAE,表明Th9細(xì)胞可引起中樞神經(jīng)炎癥。有學(xué)者發(fā)現(xiàn)EAE中IL-9R表達(dá)增加,IL-9誘導(dǎo)星形膠質(zhì)細(xì)胞高表達(dá)趨化因子CCL20,促使Th17細(xì)胞在神經(jīng)系統(tǒng)聚集產(chǎn)生免疫作用。Th9和IL-9在EAE的發(fā)生發(fā)展中發(fā)揮重要作用[37]。通過(guò)抑制IL-9的作用,EAE病情得到改善。應(yīng)用抗IL-9McAb,阻斷IL-9和IL-9R的結(jié)合,有效抑制IL-9誘導(dǎo)的炎癥。既可預(yù)防EAE的發(fā)生,又能減輕EAE病情。此外,有報(bào)道提示[38],抗IL-9McAb可能通過(guò)顯著降低特異性CD4+T細(xì)胞促發(fā)炎癥細(xì)胞亞群如Th1、Th9和Th17細(xì)胞在小鼠脊髓中的浸潤(rùn)和脫髓鞘,大大降低EAE發(fā)病率。
5 展望
CD4+T細(xì)胞常在TGF-β和IL-4共同作用下誘導(dǎo)分化為Th9細(xì)胞,是受多種因素影響的新型T細(xì)胞亞群。Th9細(xì)胞通過(guò)分泌IL-9等細(xì)胞因子參與自身免疫病、腫瘤、炎癥性疾病等多種疾病的發(fā)生發(fā)展。深入研究Th9細(xì)胞的生物學(xué)功能和自身免疫病的關(guān)系,既可更好地理解自身免疫疾病發(fā)病的機(jī)制,還能為疾病的治療、預(yù)防尋找適當(dāng)?shù)男掳悬c(diǎn)。
[參考文獻(xiàn)]
[1] ?Kaplan MH. The transcription factor network in Th9 cells [J]. Semin Immunopathol,2017,39(1):11-20.
[2] ?Koh B,Hufford MM,Pham D,et al. The ETS family transcription factors Etv5 and PU.1 function in parallel to promote Th9 cell development [J]. J Immunol,2016,197(6):2465-2472.
[3] ?劉芮辰,董琳,劉光偉.新型Th9細(xì)胞分化及功能調(diào)控的研究進(jìn)展[J].中國(guó)免疫學(xué)雜志,2019,35(5):513-520.
[4] ?Dardalhon V,Awasthi A,Kwon H,et al. IL-4 inhibits TGF-betainduced Foxp3 + T cells and together with TGF-beta,generates IL-9 + IL-10 + Foxp3(-)effector T cells [J]. Nat Immunol,2008,9(12):1347-1355.
[5] ?Veldhoen M,Uyttenhove C,van Snick J,et al. Transforming growth factor-beta ′reprograms′ the differentiation of T helper 2 cells and promotes an interleukin 9-producing subset [J]. Nat Immunol,2008,9(12):1341-1346.
[6] ?Lee JE,Zhu Z,Bai Q,et al. The Role of Interleukin-9 in Cancer [J]. Pathol Oncol Res,2019.Epub ahead of print.
[7] ?Clark RA,Schlapbach C. TH9 cells in skin disorders [J]. Semin Immunopathol,2017,39(1):47-54.
[8] ?Lu Y,Wang Q,Xue G,et al. Th9 Cells Represent a Unique Subset of CD4+ T Cells Endowed with the Ability to Eradicate Advanced Tumors [J]. Cancer Cell,2018,33(6):1048-1060.
[9] ?Végran F,Berger H,Boidot R,et al. The transcription factor IRF1 dictates the IL-21-dependent anticancer functions of TH9 cells [J]. Nat Immunol,2014,15(8):758-766.
[10] ?Liao W,Spolski R,Li P,et al. Opposing actions of IL-2 and IL-21 on Th9 differentiation correlate with their differential regulation of BCL6 expression [J]. Proc Natl Acad Sci USA,2014,111(9):3508-3513.
[11] ?Sundrud MS,Hogan SP. What′s old is new again:Batf transcription factors and Th9 cells [J]. Mucosal Immunol,2019,12(3):583-585.
[12] ?Angkasekwinai P. Th9 Cells in Allergic Disease [J]. Curr Allergy Asthma Rep,2019,19(5):29.
[13] ?Awe O,Hufford MM,Wu H,et al. PU.1 Expression in T Follicular Helper Cells Limits CD40L-Dependent Germinal Center B Cell Development [J]. J Immunol,2015, 195(8):3705-3715.
[14] ?Malik S,Sadhu S,Elesela S,et al. Transcription factor Foxo1 is essential for IL-9 induction in T helper cells [J]. Nat Commun,2017,8(1):815.
[15] ?Wang YX,Gu ZW,Cao ZW,et al. Nonylphenol can aggravate allergic rhinitis in a murine model by regulating important Thcellsubtypes and their associated cytokines [J]. Int Immunopharmacol,2019,70:260-267.
[16] ?Campos Carrascosa L,Klein M,Kitagawa Y,et al. Reciprocal regulation of the Il9 locus by counteracting activities of transcription factors IRF1 and IRF4 [J]. Nat Commun,2017,8:15366.
[17] ?Xue G,Jin G,F(xiàn)ang J,et al. IL-4 together with IL-1β induces antitumor Th9 cell differentiation in the absence of TGF-β signaling [J]. Nat Commun,2019,10(1):1376.
[18] ?Nouri-Vaskeh M,Malek Mahdavi A,Khabbazi A,et al. Lack of association between serum IL-9 levels and Beh?觭et′s disease [J]. Immunol Lett,2019,211:23-27.
[19] ?Read KA,Powell MD,Sreekumar BK,et al. In Vitro Differentiation of Effector CD4+T Helper Cell Subsets [J]. Methods Mol Biol,2019,1960:75-84.
[20] ?Richard AC,Tan C,Hawley ET,et al. The TNF-family ligand TL1A and its receptor Dr3 promote T cell-mediated allergic immunopathology by enhancing differentiation and pathogenicity of IL-9-producing T cells [J]. J Immunol,2015,194(8):3567-3582.
[21] ?Kim IK,Kim BS,Koh CH,et al. Glucocorticoid-induced tumor necrosis factor receptor-related protein co-stimulation facilitates tumor regression by inducing IL-9-producing helper T cells [J]. Nat Med,2015,21(9):1010-1017.
[22] ?Ciccia F,Guggino G,Rizzo A,et al. Potential involvement of IL-9 and Th9 cells in the pathogenesis of rheumatoid arthritis [J]. Rheumatology(Oxford),2015,54(12):2264-2272.
[23] ?Rahimi K,Ahmadi A,Hassanzadeh K,et al. Targeting the balance of T helper cell responses by curcumin in inflammatory and autoimmune states [J]. Autoimmun Rev,2019,18(7):738-748.
[24] ?Yang J,Li Q,Yang X,et al. Interleukin-9 is associated with elevated anti-double-stranded DNA antibodies in lupus-prone mice [J]. Mol Med,2015,21:364-370.
[25] ?Luk CC,Tam LS,Kwan BC,et al. Intrarenal and urinary Th9 and Th22 cytokine gene expression in lupus nephritis [J]. J Rheumatol,2015,42(7):1150-1155.
[26] ?Ou Yang H,Shi Y,Liu Z,et al. Increased interleukin-9 and CD4 IL-9 T cells in patients with systemic lupus erythematosus [J]. Mol Med Rep,2013,7:1031-1037.
[27] ?Medrano-Campillo P,Sarmiento-Soto H,?譧lvarez-Sánchez N,et al. Evaluation of the immunomodulatory effect of melatonin on the T-cell response in peripheral blood from systemic lupus erythematosus patients [J]. J Pineal Res,2015,58(2):219-226.
[28] ?Guan SY,Leng RX,Tao JH,et al. Hypoxia-inducible factor-1α:a promising herapeutic target for autoimmune diseases [J]. Expert Opin Ther Targets,2017,21(7):715-723.
[29] ?Nalleweg N,Chiriac MT,Podstawa E,et al. IL-9 and its receptor are predominantly involved in the pathogenesis of UC [J]. Gut,2015,64(5):743-755.
[30] ?Leake I. IBD. TH9 cells might have a role in the pathogenesis of ulcerative colitis[J]. Nat Rev Gastroenterol Hepatol,2014,11(8):455.
[31] ?Gerlach K,Hwang Y,Nikolaev A,et al. Th9 cell that express the transcription factor PU 1 drive T cell-mediated colitis via IL-9 receptor signaling in intestinal epithelial cells [J]. Nat Immunol,2014,15(7):676-686
[32] ?Hufford MM,Kaplan MH. A gut reaction to IL-9 [J]. Nat Immunol,2014,15(7):599-600.
[33] ?Singh TP,Sch?觟n MP,Wallbrecht K,et al. Involvement of IL-9 in Th17-associated inflammation and angiogenesis of posoriasis [J]. PLoS One,2013,8(1):e51752.
[34] ?Jia L,Wu C. Diffientiation regulation and function of Th9 cells [J]. Adv Exp Med Biol,2014,841:181-207.
[35] ?Yao X,Kong Q,Xie X,et al. Neutralization of interleukin-9 ameliorates symptoms of experimental autoimmune myasthenia gravis in rats by decreasing effector T cells and altering humoral responses [J]. Immunology,2014,143(3):396-405.
[36] ?薛海波,馬蕾,宋守君,等.橋本甲狀腺炎患者外周血Th9細(xì)胞的表達(dá)水平及意義[J].中華微生物學(xué)和免疫學(xué)雜志,2015,35(5):387-390.
[37] ?Ding X,Cao F,Cui L,et al. IL-9 signal affect s central nervous system resident cells during inflammatory stimuli [J]. Exp Mol Pathol,2015,99(3):570-574.
[38] ?Jadali Z. Th9 Cells as a New Player in Inflammatory Skin Disorders [J]. Iran J Allergy Asthma Immunol,2019,18(2):120-130.
(收稿日期:2019-05-15 ?本文編輯:顧家毓)