Toll樣受體(Toll-like receptors, TLR)是先天免疫系統(tǒng)中發(fā)揮重要作用的蛋白,也是連接先天免疫與適應性免疫的關(guān)鍵橋梁。當微生物突破機體物理屏障時,TLR能夠迅速識別并結(jié)合相應的PAMP(病原體相關(guān)分子模式),啟動信號傳導,誘導促炎細胞因子和趨化因子的表達,引發(fā)炎癥反應。除PAMP外,TLR還能夠識別內(nèi)源性危險信號(Damage-Associated Molecular Patterns, DAMP),如組織損傷時釋放的熱休克蛋白、透明質(zhì)酸降解產(chǎn)物等。這一功能使得TLR在組織修復、自身免疫疾病、腫瘤等生理病理過程中也發(fā)揮著重要的作用。
TLR廣泛分布于多種免疫細胞的表面或胞內(nèi),根據(jù)其結(jié)構(gòu)和功能可分為兩大類:細胞表面TLR和胞內(nèi)TLR,細胞表面TLR包括TLR1、TLR2、TLR4、TLR5、TLR6和TLR10,主要識別細菌、真菌或寄生蟲的膜成分。胞內(nèi)TLR包括TLR3、TLR7、TLR8和TLR9,位于細胞器膜上,負責識別核酸類分子。TLR作為免疫調(diào)節(jié)的關(guān)鍵靶點,其激動劑和抑制劑在動物炎癥模型研究和疫苗研發(fā)中具有重要的應用前景。
AbMole為全球科研客戶提供高純度、高生物活性的抑制劑、細胞因子、人源單抗、天然產(chǎn)物、熒光染料、多肽、靶點蛋白、化合物庫、抗生素等科研試劑,全球大量文獻專利引用。
圖 1. TLR signaling pathway in innate immune cells[1].
1. Resatorvid
Resatorvid(TAK-242,AbMole,M4838)是一種選擇性Toll樣受體4(TLR4)抑制劑,可通過直接結(jié)合TLR4的細胞內(nèi)結(jié)構(gòu)域,阻斷其與下游銜接蛋白(如MyD88和TRIF)的相互作用,從而抑制TLR4介導的NF-κB和促炎細胞因子(如TNF-α和IL-6)的釋放[2]。Resatorvid在RAW264.7巨噬細胞中,能顯著降低)
LPS(AbMole,M9524,Lipopolysaccharides,脂多糖)誘導的TNF-α和IL-6水平,證實其通過TLR4依賴性途徑抑制炎癥反應。也有研究表明Resatorvid(CAS No.:243984-11-4)可能通過誘導TLR4的內(nèi)吞,減少細胞膜上TLR4的可用性,從而下調(diào)下游信號通路的激活[3]。在動物實驗的應用中,Resatorvid在膿毒癥小鼠模型中通過抑制TLR4信號通路,減輕了過度炎癥反應導致的器官損傷。
圖 2.實驗人員使用AbMole的Resatorvid(TAK-242,AbMole,M4838)作為陽性對照驗證NSC23766下調(diào)巨噬細胞中炎癥因子的表達[4]。
2. TLR2-IN-C29(C29)
TLR2-IN-C29(C29,AbMole,M9063)是一種特異性TLR2抑制劑,可通過直接抑制TLR2受體活性,阻斷下游信號傳導。實驗表明,C29能顯著降低TLR2介導的NF-κB/NLRP3炎癥小體激活通路,從而抑制炎癥因子(如IL-1β)的產(chǎn)生[5]。在細菌感染模型中,C29的處理可減少病原體(如肺炎克雷伯菌)對肺泡上皮細胞(A549)的侵襲能力[6]。此外,C29可逆轉(zhuǎn)脂多糖(LPS)誘導的巨噬細胞M1型極化(促炎表型),同時促進M2型極化(抗炎表型),這一效應與抑制NAMPT/TLR2/CCR1軸相關(guān)[7]。動物層面上,TLR2-IN-C29(CAS No.:363600-92-4)已被用于急性肺損傷(ALI)、腫瘤微環(huán)境調(diào)控(在腫瘤相關(guān)腹膜間皮細胞HPMCs中,C29阻斷外泌體ANXA2誘導的TLR2激活,進而抑制腫瘤細胞遷移)、代謝疾病等動物模型。
圖 3. AbMole的TLR2-IN-C29(C29,AbMole,M9063)被用于驗證TLR2對小鼠胰腺炎的影響[8]。
3. Resiquimod(R848)
Resiquimod(R848,AbMole,M7189)是一種強效的TLR7/TLR8雙重激動劑,具有顯著的免疫調(diào)節(jié)和抗腫瘤活性。Resiquimod通過激活TLR7/8-MyD88信號通路,誘導免疫細胞的活化,增加促炎細胞因子(如IFN-α)的釋放。Resiquimod還能激活PI3K-Akt-mTOR通路,這一通路的激活與免疫細胞的增殖和功能調(diào)控密切相關(guān)[9]。Resiquimod還可促進抗原呈遞細胞(APCs)的成熟,并減少抑制性APCs的數(shù)量,從而增強免疫應答。在腫瘤研究中,Resiquimod(CAS No.:144875-48-9)被證實可激活機體的免疫系統(tǒng),例如將MDSCs(髓系來源的抑制細胞)和M2巨噬細胞轉(zhuǎn)化為抗腫瘤的免疫表型[10]。
4. Imiquimod(R 837)
Imiquimod(R 837,IMQ,AbMole,M2227)是一種TLR7激動劑,具有廣泛免疫調(diào)節(jié)活性。Imiquimod通過激活TLR7,觸發(fā)MyD88依賴的信號通路,誘導I型干擾素(如IFN-β)和促炎細胞因子(如IL-6、IL-12、TNF-α)的分泌。這一機制在抗病毒、抗寄生蟲及抗腫瘤免疫中發(fā)揮核心作用[11]。Imiquimod還是目前研究動物(小鼠、大鼠)銀屑病發(fā)病機制和藥物篩選的重要實驗工具。有研究發(fā)現(xiàn)通過每日局部涂抹Imiquimod于剃毛的小鼠背部皮膚,持續(xù)6—9天,可成功誘導銀屑病樣皮炎[12]。Imiquimod同樣可調(diào)節(jié)腫瘤的免疫微環(huán)境,例如Imiquimod(CAS No.:99011-02-6)在骨髓源性DC疫苗的抗腫瘤研究中,局部應用可誘導皮膚炎癥但會增強抗黑色素瘤效果,提示其能改善腫瘤局部免疫抑制狀態(tài)[13]。
2014年,AbMole的兩款抑制劑分別被西班牙國家心血管研究中心和美國哥倫比亞大學用于動物體內(nèi)實驗,相關(guān)科研成果發(fā)表于頂刊 Nature 和 Nature Medicine。
5. RS 09
RS 09(AbMole,M11423)是一種LPS模擬物和TLR4激動劑,可模擬LPS的結(jié)構(gòu),與TLR4/MD-2復合物結(jié)合,從而激活TLR4信號通路。研究表明,TLR4/MD-2復合物是炎癥反應的關(guān)鍵調(diào)控靶點,RS 09的結(jié)合可通過穩(wěn)定TLR4/MD-2異源四聚體的構(gòu)象,促進下游信號通路的激活[14]。RS 09還可通過激活TLR4,進一步激活NF-κB信號通路,促進促炎細胞因子(如IL-6)的釋放。例如,在巨噬細胞中,RS 09能夠上調(diào)M1型巨噬細胞標志物(如CD11c和IL-6)的表達,增強其對病原體(如鼠傷寒沙門氏菌)的免疫應答[15]。RS 09作為TLR4激動劑,常用于模擬炎癥反應,研究TLR4信號通路在疾病中的作用。例如,,RS 09(CAS No.:1449566-36-2)被用于驗證TLR4/NF-κB通路在潰瘍性結(jié)腸炎和心臟肥大小鼠模型中的作用[16]。
6. Vesatolimod (GS-9620)
Vesatolimod (GS-9620,AbMole,M2728)是一種TLR7激動劑,通過激活先天性和適應性免疫反應發(fā)揮作用,在動物實驗中具有口服活性。Vesatolimod具有較強的免疫激活能力,可刺激漿細胞樣樹突狀細胞(pDCs)和B淋巴細胞,并促進細胞因子(如干擾素)的產(chǎn)生和免疫系統(tǒng)激活[17]。Vesatolimod還具有抗病毒作用,可抑制EV-D68、HIV、HBV等病毒的復制[18]。Vesatolimod可用于神經(jīng)炎癥相關(guān)的研究,例如在MOG35-55(髓鞘少突膠質(zhì)細胞糖蛋白)誘導的自身免疫性腦脊髓炎(EAE)小鼠模型中,Vesatolimod(CAS No.:1228585-88-3)顯著改善了小鼠癥狀[19]。
7. Enpatoran(M5049)
Enpatoran(CAS No.:2101938-42-3,AbMole,M11434)是一種新型、高選擇性、強效的雙重TLR7和TLR8抑制劑,目前已被用于研究系統(tǒng)性紅斑狼瘡(SLE)、皮膚紅斑狼瘡(CLE)、皮肌炎等自身免疫疾病的動物模型。Enpatoran的作用機理主要是通過與TLR7/8的配體結(jié)合口袋結(jié)合,從而阻斷TLR7/8介導的信號傳導,減少促炎細胞因子和I型干擾素的產(chǎn)生,抑制過度激活的免疫反應[20]。
8. Motolimod(VTX-2337,VTX-378)
Motolimod(VTX-2337,AbMole,M5800)是一種TLR8的激動劑,比作用于TLR7的選擇性高50倍以上?杉せ钕忍烀庖吆瓦m應性免疫反應。在細胞實驗中,Motolimod(CAS No.:926927-61-9)可刺激人外周血單核細胞(PBMCs)產(chǎn)生TNFα和IL-12,并通過激活NF-κB通路,在單核細胞和髓樣樹突狀細胞(mDCs)中選擇性誘導TNFα和IL-12的產(chǎn)生。此外,Motolimod還能刺激自然殺傷(NK)細胞產(chǎn)生IFNγ,增強NK細胞的細胞毒性和抗體依賴的細胞介導的細胞毒性作用(ADCC)[21]。在動物實驗中,Motolimod在小鼠卵巢癌模型中可增強阿霉素(Doxorubicin)的效果[22];在獼猴實驗中,皮下注射Motolimod可顯著提高IL-1β和IL-18的血漿水平[23]。
9. CU-T12-9
CU-T12-9(AbMole,M11026)是一種高選擇性的Toll樣受體1/2(TLR1/2)異二聚體的激動劑,其EC50值為52.9 nM,對TLR1/2異二聚體具有高度特異性,而對TLR2/6沒有明顯作用。在細胞實驗中,CU-T12-9(CAS No.:1821387-73-8)通過與TLR1和TLR2結(jié)合,促進TLR1/2異二聚體復合物的形成,進而激活NF-κB信號通路,誘導下游效應分子TNF-α、IL-10和iNOS的表達[24]。在動物實驗中,CU-T12-9可同時激活先天免疫系統(tǒng)和適應性免疫系統(tǒng),提高機體的免疫反應。
圖 4. CU-T12-9的作用機理和抑制活性測試[24]
10. TLR4-IN-C34(C34)
TLR4-IN-C34(C34,AbMole,M9651)是一種強效且特異性的TLR4抑制劑,可通過直接結(jié)合TLR4并抑制其信號傳導。在細胞實驗中,TLR4-IN-C34可抑制LPS誘導的NF-κB信號通路激活,減少促炎細胞因子如TNF-α、IL-1β和IL-6的產(chǎn)生[25]。TLR4-IN-C34(CAS No.:40592-88-9)在BV2小膠質(zhì)細胞中,可顯著降低TLR4、MyD88、NLRP3的表達水平以及NF-κB和IκBα蛋白的磷酸化水平,同時減少NO的產(chǎn)生和iNOS、COX-2的表達。TLR4-IN-C34在大鼠急性腎損傷模型中,降低了血清肌酐水平,并減輕腎組織病理損傷,減少腎組織中MAPK和MyD88的表達以及炎癥因子IL-8、IL-1β和IL-12的含量[26]。
11. TH1020
TH1020(AbMole,M7408)是一種高特異性Toll樣受體5(TLR5)抑制劑,通過直接結(jié)合TLR5受體的胞外域,選擇性阻斷TLR5與鞭毛蛋白(Flagellin)的相互作用。鞭毛蛋白是細菌鞭毛的主要結(jié)構(gòu)蛋白,鞭毛蛋白與TLR5的相互作用是宿主識別細菌感染的重要機制之一。在分子機制上,TH1020(CAS No.:1841460-82-9)通過競爭性抑制鞭毛蛋白與TLR5的結(jié)合,阻斷MyD88依賴型信號通路,減少IκBα磷酸化及NF-κB p65亞基核轉(zhuǎn)位,同時抑制MAPK(p38/ERK)磷酸化,從而下調(diào)促炎細胞因子(TNF-α、IL-8)的表達[27]。
12. ODN 1826(CpG 1826)
ODN 1826(CpG 1826,AbMole,M9904)是一種含有CpG基序的寡脫氧核苷酸,可通過激活Toll樣受體9(TLR9)通路,從而調(diào)控免疫反應和細胞信號傳導。在科研應用中,ODN 1826(CAS No.:202668-42-6)被廣泛用于激發(fā)Th1型免疫反應。例如,在倉鼠模型中,ODN 1826與寄生蟲抗原(CSAg)聯(lián)合使用時,顯著增強了宿主對寄生蟲的清除能力,寄生蟲減少率分別達到32.95%(ODN 1826 + CSAg)和21.49%(ODN 1826單獨使用),表明其能夠通過Th1樣反應增強宿主的防御能力[28]。此外,ODN 1826還被用于三組分疫苗的構(gòu)建,例如與半抗原(GNE)和載體蛋白(OVA)共價連接,在小鼠模型中成功誘導了高特異性抗體產(chǎn)生[29]。
| 品名 |
目錄號 |
靶點 |
| Resatorvid |
M4838 |
TLR4抑制劑 |
| C29 |
M9063 |
TLR2抑制劑 |
| Resiquimod |
M7189 |
TLR7/TLR8雙重激動劑 |
| Imiquimod |
M2227 |
TLR7激動劑 |
| RS 09 |
M11423 |
TLR4 激動劑 |
| Vesatolimod |
M2728 |
TLR7激動劑 |
| Enpatoran |
M11434 |
TLR7/TLR8雙重抑制劑 |
| Motolimod |
M5800 |
TLR8激動劑 |
| CU-T12-9 |
M11026 |
TLR1/2 異二聚體激動劑 |
| TLR4-IN-C34 |
M9651 |
TLR4抑制劑 |
| TH 1020 |
M7408 |
TLR5抑制劑 |
| ODN 1826 |
M9904 |
TLR9激動劑 |
| Diprovocim |
M25485 |
TLR1/2 異二聚體激動劑 |
| E6446 |
M11308 |
TLR7/9抑制劑 |
| CU-CPT 4a |
M6637 |
TLR3抑制劑 |
| Hydroxychloroquine |
M11408 |
TLR7/9抑制劑 |
| Chloroquine |
M9559 |
TLR3/7/8/9抑制劑 |
表 1. 常用的TLRs抑制劑和激動劑
*本文所述產(chǎn)品僅供科研使用
參考文獻及鳴謝
[1] Duan, T.; Du, Y.; Xing, C.; et al. Toll-like receptor signaling and its role in cell-mediated immunity. 2022,
13, 812774.
[2] Bian, B.; Miao, X.; Zhao, X.; et al. Impacts of monosaccharide composition on immunomodulation by cello-pentaose, manno-pentaose, and xylo-pentaose: Unraveling the underlying molecular mechanisms.
Carbohydrate polymers 2024,
334, 122006.
[3] Geng, X.; Xia, X.; Liang, Z.; et al. Tropomodulin1 exacerbates inflammatory response in macrophages by negatively regulating LPS-induced TLR4 endocytosis.
Cellular and molecular life sciences : CMLS 2024,
81 (1), 402.
[4] Fu, H.; Zhang, P.; Zhao, X. D.; et al. Interfering with Rac1-activation during neonatal monocyte-macrophage differentiation influences the inflammatory responses of M1 macrophages.
Cell death & disease 2023,
14 (9), 619.
[5] Gan, A.; Chen, H.; Lin, F.; et al. Sanzi Yangqin Decoction improved acute lung injury by regulating the TLR2-mediated NF-kappaB/NLRP3 signaling pathway and inhibiting the activation of NLRP3 inflammasome.
Phytomedicine : international journal of phytotherapy and phytopharmacology 2025,
139, 156438.
[6] Ding, R.; Yu, J.; Ke, W.; et al. TLR2 regulates Moraxella catarrhalis adhesion to and invasion into alveolar epithelial cells and mediates inflammatory responses.
Virulence 2024,
15 (1), 2298548.
[7] Wang, L.; Wang, J.; Han, L.; et al. Palmatine Attenuated Lipopolysaccharide-Induced Acute Lung Injury by Inhibiting M1 Phenotype Macrophage Polarization via NAMPT/TLR2/CCR1 Signaling.
Journal of agricultural and food chemistry 2024.
[8] Li, L.; Liu, Q.; Le, C.; et al. Toll-like receptor 2 deficiency alleviates acute pancreatitis by inactivating the NF-κB/NLRP3 pathway.
International immunopharmacology 2023,
121, 110547.
[9] Wang, H.; Chen, H.; Liu, S.; et al. Costimulation of gammadeltaTCR and TLR7/8 promotes Vdelta2 T-cell antitumor activity by modulating mTOR pathway and APC function.
Journal for immunotherapy of cancer 2021,
9 (12).
[10] Liang, X.; Li, X.; Wu, R.; et al. Breaking the Tumor Chronic Inflammation Balance with a Programmable Release and Multi-Stimulation Engineering Scaffold for Potent Immunotherapy.
Advanced science (Weinheim, Baden-Wurttemberg, Germany) 2024,
11 (28), e2401377.
[11] Hamie, M.; Najm, R.; Deleuze-Masquefa, C.; et al. Imiquimod Targets Toxoplasmosis Through Modulating Host Toll-Like Receptor-MyD88 Signaling.
Frontiers in immunology 2021,
12, 629917.
[12] Wu, X.; Yin, Q.; Wang, J.; et al. Novel RNA polymerase I inhibitor CX-5461 suppresses imiquimod-induced experimental psoriasis.
Experimental dermatology 2023,
32 (1), 91-99.
[13] Ren, S.; Wang, Q.; Zhang, Y.; et al. Imiquimod enhances the potency of an exogenous BM-DC based vaccine against mouse melanoma.
International immunopharmacology 2018,
64, 69-77.
[14] Zhang, X.; Wang, Y.; Wang, H.; et al. Exploring Methamphetamine Nonenantioselectively Targeting Toll-like Receptor 4/Myeloid Differentiation Protein 2 by in Silico Simulations and Wet-Lab Techniques.
Journal of chemical information and modeling 2020,
60 (3), 1607-1613.
[15] Zhao, C.; Chen, H.; Liang, H.; et al. Lactobacillus plantarum RS-09 Induces M1-Type Macrophage Immunity Against Salmonella Typhimurium Challenge via the TLR2/NF-kappaB Signalling Pathway.
Frontiers in pharmacology 2022,
13, 832245.
[16] Liu, B.; Yu, J.; Zhang, J.; et al. TLR4/NF-κB-mediated M1 macrophage polarization contributes to the promotive effects of ETS2 on ulcerative colitis.
European journal of medical research 2025,
30 (1), 668.
[17] SenGupta, D.; Brinson, C.; DeJesus, E.; et al. The TLR7 agonist vesatolimod induced a modest delay in viral rebound in HIV controllers after cessation of antiretroviral therapy.
Science translational medicine 2021,
13 (599).
[18] Lee, G.; Kang, H. R.; Kim, A.; et al. Antiviral effect of vesatolimod (GS-9620) against foot-and-mouth disease virus both in vitro and invivo.
Antiviral research 2022,
205, 105384.
[19] Jiang, X.; Song, Y.; Fang, J.; et al. Neuroprotective effect of Vesatolimod in an experimental autoimmune encephalomyelitis mice model.
International immunopharmacology 2023,
116, 109717.
[20] Klopp-Schulze, L.; Gopalakrishnan, S.; Yalkinoglu, O.; et al. Asia-Inclusive Global Development of Enpatoran: Results of an Ethno-Bridging Study, Intrinsic/Extrinsic Factor Assessments and Disease Trajectory Modeling to Inform Design of a Phase II Multiregional Clinical Trial.
Clinical pharmacology and therapeutics 2024,
115 (6), 1346-1357.
[21] Lu, H.; Dietsch, G. N.; Matthews, M. A.; et al. VTX-2337 is a novel TLR8 agonist that activates NK cells and augments ADCC.
Clinical cancer research : an official journal of the American Association for Cancer Research 2012,
18 (2), 499-509.
[22] Monk, B. J.; Brady, M. F.; Aghajanian, C.; et al. A phase 2, randomized, double-blind, placebo- controlled study of chemo-immunotherapy combination using motolimod with pegylated liposomal doxorubicin in recurrent or persistent ovarian cancer: a Gynecologic Oncology Group partners study.
Annals of oncology : official journal of the European Society for Medical Oncology 2017,
28 (5), 996-1004.
[23] Dietsch, G. N.; Lu, H.; Yang, Y.; et al. Coordinated Activation of Toll-Like Receptor8 (TLR8) and NLRP3 by the TLR8 Agonist, VTX-2337, Ignites Tumoricidal Natural Killer Cell Activity.
PloS one 2016,
11 (2), e0148764.
[24] Cheng, K.; Gao, M.; Godfroy, J. I.; et al. Specific activation of the TLR1-TLR2 heterodimer by small-molecule agonists. 2015,
1 (3), e1400139.
[25] 張姍姍; 劉漫; 劉冬妮; et al. TLR4-IN-C34通過抑制TLR4/MyD88/NF-κB/NLRP3信號通路減輕脂多糖誘導的BV2小膠質(zhì)細胞炎癥反應. 2021.
[26] Abdelsalam, H. M.; Helal, M. G.; Abu-Elsaad, N. M. J. I. j. o. b. m. s. TLR4‐IN‐C34 protects against acute kidney injury via modulating TLR4/MyD88/NF-κb axis, MAPK, and apoptosis. 2022,
25 (11), 1334.
[27] Yan, L.; Liang, J.; Yao, C.; et al. Pyrimidine triazole thioether derivatives as Toll‐like receptor 5 (TLR5)/flagellin complex inhibitors. 2016,
11 (8), 822-826.
[28] Kaewraemruaen, C.; Sermswan, R. W.; Wongratanacheewin, S. CpG oligodeoxynucleotides with crude parasite antigens reduce worm recovery in Opisthorchis viverrini infected hamsters.
Acta tropica 2016,
164, 395-401.
[29] Kimishima, A.; Olson, M. E.; Janda, K. D. Investigations into the efficacy of multi-component cocaine vaccines.
Bioorganic & medicinal chemistry letters 2018,
28 (16), 2779-2783.