Myeloid-derived suppressor cells (MDSC) are a heterogeneous group of mononuclear and polymorphonuclear myeloid cells, which are present at very low numbers in healthy subjects, but can expand substantially under disease conditions. Depending on disease type and stage, MDSC comprise varying amounts of immature and mature differentiation stages of myeloid cells. Validated unique phenotypic markers for MDSC are still lacking. Therefore, the functional analysis of these cells is of central importance for their identification and characterization. Various disease-promoting and immunosuppressive functions of MDSC are reported in the literature. Among those, the capacity to modulate the activity of T cells is by far the most often used and best-established read-out system. In this review, we critically evaluate the assays available for the functional analysis of human and murine MDSC under in vitro and in vivo conditions. We also discuss critical issues and controls associated with those assays. We aim at providing suggestions and recommendations useful for the contemporary biological characterization of MDSC.

Cellular and Molecular Immunology Lab Vrije Universiteit Brussel Brussels Belgium

Centro Integrativo de Biología y Química Aplicada Universidad Bernardo O'Higgins Santiago Chile

Department of Basic Oncology Hacettepe University Cancer Institute Ankara Turkey

e Duve Institute Université catholique de Louvain Avenue Hippocrate 74 1200 Brussels Belgium

Institute of Experimental Pharmacology and Toxicology Slovak Academy of Sciences Dubravska cesta 9 841 04 Bratislava Slovak Republic

Institute of Immunology Friedrich Loeffler Institut Federal Research Institute for Animal Health Greifswald Insel Riems Germany and Faculty of Mathematics and Natural Sciences University of Greifswald Greifswald Germany

Institute of Immunology University of Münster Münster Germany

Instituto de Biologia Molecular e Celular University of Porto Porto Portugal

Instituto de Investigação e Inovação em Saúde University of Porto Porto Portugal

Laboratory of Molecular and Cellular Immunology Institute of Molecular Genetics AS CR Videnska 1083 142 20 Prague 4 Czech Republic

Molecular Oncology group Institute for Medical Research University of Belgrade Belgrade Republic of Serbia

Myeloid Cell Immunology Lab VIB Center for Inflammation Research Brussels Belgium

Research Division Department of Otorhinolaryngology West German Cancer Center University Hospital Essen Hufelandstrasse 55 45122 Essen Germany

See more in PubMed

Pradeu T, Cooper EL. The danger theory: 20 years later. Front Immunol. 2012;3:287. doi: 10.3389/fimmu.2012.00287. PubMed DOI PMC

Libby P. Inflammatory mechanisms: the molecular basis of inflammation and disease. Nutr Rev. 2007;65:S140-6. doi: 10.1301/nr.2007.dec.S140-S146. PubMed DOI

Iqbal AJ, Fisher EA, Greaves DR. Inflammation-a critical appreciation of the role of myeloid cells. Microbiol Spectr. 2016 doi: 10.1128/microbiolspec.MCHD-0027-2016. PubMed DOI PMC

Gabrilovich DI. Myeloid-derived suppressor cells. Cancer Immunol Res. 2017;5:3–8. doi: 10.1158/2326-6066.CIR-16-0297. PubMed DOI PMC

Bronte V, Brandau S, Chen S-H, Colombo MP, Frey AB, Greten TF, Mandruzzato S, Murray PJ, Ochoa A, Ostrand-Rosenberg S, Rodriguez PC, Sica A, Umansky V, Vonderheide RH, Gabrilovich DI. Recommendations for myeloid-derived suppressor cell nomenclature and characterization standards. Nat Commun. 2016;7:12150. doi: 10.1038/ncomms12150. PubMed DOI PMC

Haile LA, Greten TF, Korangy F. Immune suppression: the hallmark of myeloid derived suppressor cells. Immunol Invest. 2012;41:581–594. doi: 10.3109/08820139.2012.680635. PubMed DOI PMC

Weber J, Gibney G, Kudchadkar R, Yu B, Cheng P, Martinez AJ, Kroeger J, Richards A, McCormick L, Moberg V, Cronin H, Zhao X, Schell M, Chen YA. Phase I/II Study of metastatic melanoma patients treated with nivolumab who had progressed after ipilimumab. Cancer Immunol Res. 2016;4:345–353. doi: 10.1158/2326-6066.CIR-15-0193. PubMed DOI PMC

de Coana YP, Wolodarski M, Poschke I, Yoshimoto Y, Yang Y, Nystrom M, Edback U, Brage SE, Lundqvist A, Masucci GV, Hansson J, Kiessling R. Ipilimumab treatment decreases monocytic MDSCs and increases CD8 effector memory T cells in long-term survivors with advanced melanoma. Oncotarget. 2017;8:21539–21553. doi: 10.18632/oncotarget.15368. PubMed DOI PMC

Chesney JA, Mitchell RA, Yaddanapudi K. Myeloid-derived suppressor cells-a new therapeutic target to overcome resistance to cancer immunotherapy. J Leukoc Biol. 2017;102:727–740. doi: 10.1189/jlb.5VMR1116-458RRR. PubMed DOI PMC

Monu NR, Frey AB. Myeloid-derived suppressor cells and anti-tumor T cells: a complex relationship. Immunol Invest. 2012;41:595–613. doi: 10.3109/08820139.2012.673191. PubMed DOI PMC

Srivastava MK, Sinha P, Clements VK, Rodriguez P, Ostrand-Rosenberg S. Myeloid-derived suppressor cells inhibit T-cell activation by depleting cystine and cysteine. Cancer Res. 2010;70:68–77. doi: 10.1158/0008-5472.CAN-09-2587. PubMed DOI PMC

Raber PL, Thevenot P, Sierra R, Wyczechowska D, Halle D, Ramirez ME, Ochoa AC, Fletcher M, Velasco C, Wilk A, Reiss K, Rodriguez PC. Subpopulations of myeloid-derived suppressor cells impair T cell responses through independent nitric oxide-related pathways. Int J Cancer. 2014;134:2853–2864. doi: 10.1002/ijc.28622. PubMed DOI PMC

Youn J-I, Collazo M, Shalova IN, Biswas SK, Gabrilovich DI. Characterization of the nature of granulocytic myeloid-derived suppressor cells in tumor-bearing mice. J Leukoc Biol. 2012;91:167–181. doi: 10.1189/jlb.0311177. PubMed DOI PMC

Liu C, Yu S, Kappes J, Wang J, Grizzle WE, Zinn KR, Zhang H-G. Expansion of spleen myeloid suppressor cells represses NK cell cytotoxicity in tumor-bearing host. Blood. 2007;109:4336–4342. doi: 10.1182/blood-2006-09-046201. PubMed DOI PMC

Knaul JK, Jörg S, Oberbeck-Mueller D, Heinemann E, Scheuermann L, Brinkmann V, Mollenkopf H-J, Yeremeev V, Kaufmann SHE, Dorhoi A. Lung-residing myeloid-derived suppressors display dual functionality in murine pulmonary tuberculosis. Am J Respir Crit Care Med. 2014;190:1053–1066. doi: 10.1164/rccm.201405-0828OC. PubMed DOI

Li H, Han Y, Guo Q, Zhang M, Cao X. Cancer-expanded myeloid-derived suppressor cells induce anergy of NK cells through membrane-bound TGF-beta 1. J Immunol. 2009;182:240–249. doi: 10.4049/jimmunol.182.1.240. PubMed DOI

Rieber N, Singh A, Öz H, Carevic M, Bouzani M, Amich J, Ost M, Ye Z, Ballbach M, Schäfer I, Mezger M, Klimosch SN, Weber ANR, Handgretinger R, Krappmann S, Liese J, Engeholm M, Schüle R, Salih HR, et al. Pathogenic fungi regulate immunity by inducing neutrophilic myeloid-derived suppressor cells. Cell Host Microbe. 2015;17:507–514. doi: 10.1016/j.chom.2015.02.007. PubMed DOI PMC

Gabrilovich DI, Nagaraj S. Myeloid-derived suppressor cells as regulators of the immune system. Nat Rev Immunol. 2009;9:162–174. doi: 10.1038/nri2506. PubMed DOI PMC

Kusmartsev S, Nefedova Y, Yoder D, Gabrilovich DI. Antigen-specific inhibition of CD8+ T cell response by immature myeloid cells in cancer is mediated by reactive oxygen species. J Immunol. 2004;172:989–999. doi: 10.4049/jimmunol.172.2.989. PubMed DOI

Nagaraj S, Gupta K, Pisarev V, Kinarsky L, Sherman S, Kang L, Herber DL, Schneck J, Gabrilovich DI. Altered recognition of antigen is a mechanism of CD8+ T cell tolerance in cancer. Nat Med. 2007;13:828–835. doi: 10.1038/nm1609. PubMed DOI PMC

Youn J-I, Nagaraj S, Collazo M, Gabrilovich DI. Subsets of myeloid-derived suppressor cells in tumor-bearing mice. J Immunol. 2008;181:5791–5802. doi: 10.4049/jimmunol.181.8.5791. PubMed DOI PMC

Huang B, Pan P-Y, Li Q, Sato AI, Levy DE, Bromberg J, Divino CM, Chen S-H. Gr-1+ CD115+ immature myeloid suppressor cells mediate the development of tumor-induced T regulatory cells and T-cell anergy in tumor-bearing host. Cancer Res. 2006;66:1123–1131. doi: 10.1158/0008-5472.CAN-05-1299. PubMed DOI

Hanson EM, Clements VK, Sinha P, Ilkovitch D, Ostrand-Rosenberg S. Myeloid-derived suppressor cells down-regulate L-selectin expression on CD4+ and CD8+ T cells. J Immunol. 2009;183:937–944. doi: 10.4049/jimmunol.0804253. PubMed DOI PMC

Schmid M, Zimara N, Wege AK, Ritter U. Myeloid-derived suppressor cell functionality and interaction with Leishmania major parasites differ in C57BL/6 and BALB/c mice. Eur J Immunol. 2014;44:3295–3306. doi: 10.1002/eji.201344335. PubMed DOI

Su N, Yue Y, Xiong S. Monocytic myeloid-derived suppressor cells from females, but not males, alleviate CVB3-induced myocarditis by increasing regulatory and CD4(+)IL-10(+) T cells. Sci Rep. 2016;6:22658. doi: 10.1038/srep22658. PubMed DOI PMC

Carretero-Iglesia L, Bouchet-Delbos L, Louvet C, Drujont L, Segovia M, Merieau E, Chiffoleau E, Josien R, Hill M, Cuturi M-C, Moreau A. Comparative study of the immunoregulatory capacity of in vitro generated tolerogenic dendritic cells, suppressor macrophages, and myeloid-derived suppressor cells. Transplantation. 2016;100:2079–2089. doi: 10.1097/TP.0000000000001315. PubMed DOI

Sierra RA, Thevenot P, Raber PL, Cui Y, Parsons C, Ochoa AC, Trillo-Tinoco J, Del Valle L, Rodriguez PC. Rescue of notch-1 signaling in antigen-specific CD8+ T cells overcomes tumor-induced T-cell suppression and enhances immunotherapy in cancer. Cancer Immunol Res. 2014;2:800–811. doi: 10.1158/2326-6066.CIR-14-0021. PubMed DOI PMC

Corzo CA, Condamine T, Lu L, Cotter MJ, Youn J-I, Cheng P, Cho H-I, Celis E, Quiceno DG, Padhya T, McCaffrey TV, McCaffrey JC, Gabrilovich DI. HIF-1α regulates function and differentiation of myeloid-derived suppressor cells in the tumor microenvironment. J Exp Med. 2010;207:2439–2453. doi: 10.1084/jem.20100587. PubMed DOI PMC

Bronte V, Wang M, Overwijk WW, Surman DR, Pericle F, Rosenberg SA, Restifo NP. Apoptotic death of CD8+ T lymphocytes after immunization: induction of a suppressive population of Mac-1+/Gr-1+ cells. J Immunol. 1998;161:5313–5320. PubMed PMC

Moses K, Klein JC, Männ L, Klingberg A, Gunzer M, Brandau S. Survival of residual neutrophils and accelerated myelopoiesis limit the efficacy of antibody-mediated depletion of Ly-6G+ cells in tumor-bearing mice. J Leukoc Biol. 2016;99:811–823. doi: 10.1189/jlb.1HI0715-289R. PubMed DOI

Clavijo PE, Moore EC, Chen J, Davis RJ, Friedman J, Kim Y, Van Waes C, Chen Z, Allen CT. Resistance to CTLA-4 checkpoint inhibition reversed through selective elimination of granulocytic myeloid cells. Oncotarget. 2017;8:55804–55820. doi: 10.18632/oncotarget.18437. PubMed DOI PMC

Vincent J, Mignot G, Chalmin F, Ladoire S, Bruchard M, Chevriaux A, Martin F, Apetoh L, Rébé C, Ghiringhelli F. 5-Fluorouracil selectively kills tumor-associated myeloid-derived suppressor cells resulting in enhanced T cell-dependent antitumor immunity. Cancer Res. 2010;70:3052–3061. doi: 10.1158/0008-5472.CAN-09-3690. PubMed DOI

Highfill SL, Cui Y, Giles AJ, Smith JP, Zhang H, Morse E, Kaplan RN, Mackall CL. Disruption of CXCR2-mediated MDSC tumor trafficking enhances anti-PD1 efficacy. Sci Transl Med. 2014;6:237ra67. doi: 10.1126/scitranslmed.3007974. PubMed DOI PMC

Nefedova Y, Fishman M, Sherman S, Wang X, Beg AA, Gabrilovich DI. Mechanism of all-trans retinoic acid effect on tumor-associated myeloid-derived suppressor cells. Cancer Res. 2007;67:11021–11028. doi: 10.1158/0008-5472.CAN-07-2593. PubMed DOI

Serafini P, Meckel K, Kelso M, Noonan K, Califano J, Koch W, Dolcetti L, Bronte V, Borrello I. Phosphodiesterase-5 inhibition augments endogenous antitumor immunity by reducing myeloid-derived suppressor cell function. J Exp Med. 2006;203:2691–2702. doi: 10.1084/jem.20061104. PubMed DOI PMC

De Santo C, Serafini P, Marigo I, Dolcetti L, Bolla M, Del Soldato P, Melani C, Guiducci C, Colombo MP, Iezzi M, Musiani P, Zanovello P, Bronte V. Nitroaspirin corrects immune dysfunction in tumor-bearing hosts and promotes tumor eradication by cancer vaccination. Proc Natl Acad Sci USA. 2005;102:4185–4190. doi: 10.1073/pnas.0409783102. PubMed DOI PMC

Nagaraj S, Youn J-I, Weber H, Iclozan C, Lu L, Cotter MJ, Meyer C, Becerra CR, Fishman M, Antonia S, Sporn MB, Liby KT, Rawal B, Lee J-H, Gabrilovich DI. Anti-inflammatory triterpenoid blocks immune suppressive function of MDSCs and improves immune response in cancer. Clin Cancer Res. 2010;16:1812–1823. doi: 10.1158/1078-0432.CCR-09-3272. PubMed DOI PMC

Yu J, Du W, Yan F, Wang Y, Li H, Cao S, Yu W, Shen C, Liu J, Ren X. Myeloid-derived suppressor cells suppress antitumor immune responses through IDO expression and correlate with lymph node metastasis in patients with breast cancer. J Immunol. 2013;190:3783–3797. doi: 10.4049/jimmunol.1201449. PubMed DOI

Hoechst B, Ormandy LA, Ballmaier M, Lehner F, Krüger C, Manns MP, Greten TF, Korangy F. A new population of myeloid-derived suppressor cells in hepatocellular carcinoma patients induces CD4(+)CD25(+)Foxp3(+) T cells. Gastroenterology. 2008;135:234–243. doi: 10.1053/j.gastro.2008.03.020. PubMed DOI

Brandau S, Trellakis S, Bruderek K, Schmaltz D, Steller G, Elian M, Suttmann H, Schenck M, Welling J, Zabel P, Lang S. Myeloid-derived suppressor cells in the peripheral blood of cancer patients contain a subset of immature neutrophils with impaired migratory properties. J Leukoc Biol. 2011;89:311–317. doi: 10.1189/jlb.0310162. PubMed DOI

Obermajer N, Muthuswamy R, Lesnock J, Edwards RP, Kalinski P. Positive feedback between PGE2 and COX2 redirects the differentiation of human dendritic cells toward stable myeloid-derived suppressor cells. Blood. 2011;118:5498–5505. doi: 10.1182/blood-2011-07-365825. PubMed DOI PMC

Pinton L, Solito S, Damuzzo V, Francescato S, Pozzuoli A, Berizzi A, Mocellin S, Rossi CR, Bronte V, Mandruzzato S. Activated T cells sustain myeloid-derived suppressor cell-mediated immune suppression. Oncotarget. 2016;7:1168–1184. doi: 10.18632/oncotarget.6662. PubMed DOI PMC

Jordan KR, Kapoor P, Spongberg E, Tobin RP, Gao D, Borges VF, McCarter MD. Immunosuppressive myeloid-derived suppressor cells are increased in splenocytes from cancer patients. Cancer Immunol Immunother. 2017;66:503–513. doi: 10.1007/s00262-016-1953-z. PubMed DOI PMC

Lechner MG, Liebertz DJ, Epstein AL. Characterization of cytokine-induced myeloid-derived suppressor cells from normal human peripheral blood mononuclear cells. J Immunol. 2010;185:2273–2284. doi: 10.4049/jimmunol.1000901. PubMed DOI PMC

Mandruzzato S, Brandau S, Britten CM, Bronte V, Damuzzo V, Gouttefangeas C, Maurer D, Ottensmeier C, van der Burg SH, Welters MJP, Walter S. Toward harmonized phenotyping of human myeloid-derived suppressor cells by flow cytometry: results from an interim study. Cancer Immunol Immunother. 2016;65:161–169. doi: 10.1007/s00262-015-1782-5. PubMed DOI PMC

Dumitru CA, Moses K, Trellakis S, Lang S, Brandau S. Neutrophils and granulocytic myeloid-derived suppressor cells: immunophenotyping, cell biology and clinical relevance in human oncology. Cancer Immunol Immunother. 2012;61:1155–1167. doi: 10.1007/s00262-012-1294-5. PubMed DOI PMC

Kusmartsev S, Nagaraj S, Gabrilovich DI. Tumor-associated CD8+ T cell tolerance induced by bone marrow-derived immature myeloid cells. J Immunol. 2005;175:4583–4592. doi: 10.4049/jimmunol.175.7.4583. PubMed DOI PMC

Heuvers ME, Muskens F, Bezemer K, Lambers M, Dingemans A-MC, Groen HJM, Smit EF, Hoogsteden HC, Hegmans JPJJ, Aerts JGJV. Arginase-1 mRNA expression correlates with myeloid-derived suppressor cell levels in peripheral blood of NSCLC patients. Lung Cancer. 2013;81:468–474. doi: 10.1016/j.lungcan.2013.06.005. PubMed DOI

Rodriguez PC, Hernandez CP, Quiceno D, Dubinett SM, Zabaleta J, Ochoa JB, Gilbert J, Ochoa AC. Arginase I in myeloid suppressor cells is induced by COX-2 in lung carcinoma. J Exp Med. 2005;202:931–939. doi: 10.1084/jem.20050715. PubMed DOI PMC

Rodriguez PC, Ernstoff MS, Hernandez C, Atkins M, Zabaleta J, Sierra R, Ochoa AC. Arginase I-producing myeloid-derived suppressor cells in renal cell carcinoma are a subpopulation of activated granulocytes. Cancer Res. 2009;69:1553–1560. doi: 10.1158/0008-5472.CAN-08-1921. PubMed DOI PMC

Liu C-Y, Wang Y-M, Wang C-L, Feng P-H, Ko H-W, Liu Y-H, Wu Y-C, Chu Y, Chung F-T, Kuo C-H, Lee K-Y, Lin S-M, Lin H-C, Wang C-H, Yu C-T, Kuo H-P. Population alterations of l-arginase- and inducible nitric oxide synthase-expressed CD11b+/CD14/CD15+/CD33+ myeloid-derived suppressor cells and CD8+ T lymphocytes in patients with advanced-stage non-small cell lung cancer. J Cancer Res Clin Oncol. 2010;136:35–45. doi: 10.1007/s00432-009-0634-0. PubMed DOI PMC

Toor SM, Syed Khaja AS, El Salhat H, Bekdache O, Kanbar J, Jaloudi M, Elkord E. Increased levels of circulating and tumor-infiltrating granulocytic myeloid cells in colorectal cancer patients. Front Immunol. 2016;7:560. doi: 10.3389/fimmu.2016.00560. PubMed DOI PMC

Munn DH, Shafizadeh E, Attwood JT, Bondarev I, Pashine A, Mellor AL. Inhibition of T cell proliferation by macrophage tryptophan catabolism. J Exp Med. 1999;189:1363–1372. doi: 10.1084/jem.189.9.1363. PubMed DOI PMC

Toor SM, Syed Khaja AS, El Salhat H, Faour I, Kanbar J, Quadri AA, Albashir M, Elkord E. Myeloid cells in circulation and tumor microenvironment of breast cancer patients. Cancer Immunol Immunother. 2017;66:753–764. doi: 10.1007/s00262-017-1977-z. PubMed DOI PMC

Cao LY, Chung J-S, Teshima T, Feigenbaum L, Cruz PD, Jacobe HT, Chong BF, Ariizumi K. Myeloid-derived suppressor cells in psoriasis are an expanded population exhibiting diverse T-cell-suppressor mechanisms. J Invest Dermatol. 2016;136:1801–1810. doi: 10.1016/j.jid.2016.02.816. PubMed DOI PMC

Wesolowski R, Markowitz J, Carson WE. Myeloid derived suppressor cells—a new therapeutic target in the treatment of cancer. J Immunother Cancer. 2013;1:10. doi: 10.1186/2051-1426-1-10. PubMed DOI PMC

Luyckx A, Schouppe E, Rutgeerts O, Lenaerts C, Fevery S, Devos T, Dierickx D, Waer M, Van Ginderachter JA, Billiau AD. G-CSF stem cell mobilization in human donors induces polymorphonuclear and mononuclear myeloid-derived suppressor cells. Clin Immunol. 2012;143:83–87. doi: 10.1016/j.clim.2012.01.011. PubMed DOI

Walsh NC, Kenney LL, Jangalwe S, Aryee K-E, Greiner DL, Brehm MA, Shultz LD. Humanized mouse models of clinical disease. Annu Rev Pathol. 2017;12:187–215. doi: 10.1146/annurev-pathol-052016-100332. PubMed DOI PMC

Wu H, Zhen Y, Ma Z, Li H, Yu J, Xu Z-G, Wang X-Y, Yi H, Yang Y-G. Arginase-1-dependent promotion of TH17 differentiation and disease progression by MDSCs in systemic lupus erythematosus. Sci Transl Med. 2016;8:331ra40. doi: 10.1126/scitranslmed.aae0482. PubMed DOI PMC

Liu G, Hu Y, Xiao J, Li X, Li Y, Tan H, Zhao Y, Cheng D, Shi H. 99mTc-labelled anti-CD11b SPECT/CT imaging allows detection of plaque destabilization tightly linked to inflammation. Sci Rep. 2016;6:20900. doi: 10.1038/srep20900. PubMed DOI PMC

Eisenblaetter M, Flores-Borja F, Lee JJ, Wefers C, Smith H, Hueting R, Cooper MS, Blower PJ, Patel D, Rodriguez-Justo M, Milewicz H, Vogl T, Roth J, Tutt A, Schaeffter T, Ng T. Visualization of tumor-immune interaction—target-specific imaging of S100A8/A9 reveals pre-metastatic niche establishment. Theranostics. 2017;7:2392–2401. doi: 10.7150/thno.17138. PubMed DOI PMC

Moses K, Brandau S. Human neutrophils: their role in cancer and relation to myeloid-derived suppressor cells. Semin Immunol. 2016;28:187–196. doi: 10.1016/j.smim.2016.03.018. PubMed DOI

Condamine T, Dominguez GA, Youn J-I, Kossenkov AV, Mony S, Alicea-Torres K, Tcyganov E, Hashimoto A, Nefedova Y, Lin C, Partlova S, Garfall A, Vogl DT, Xu X, Knight SC, Malietzis G, Lee GH, Eruslanov E, Albelda SM, et al. Lectin-type oxidized LDL receptor-1 distinguishes population of human polymorphonuclear myeloid-derived suppressor cells in cancer patients. Sci Immunol. 2016;1:aaf8943. doi: 10.1126/sciimmunol.aaf8943. PubMed DOI PMC

Trellakis S, Bruderek K, Hütte J, Elian M, Hoffmann TK, Lang S, Brandau S. Granulocytic myeloid-derived suppressor cells are cryosensitive and their frequency does not correlate with serum concentrations of colony-stimulating factors in head and neck cancer. Innate Immun. 2013;19:328–336. doi: 10.1177/1753425912463618. PubMed DOI

Gregori S, Tomasoni D, Pacciani V, Scirpoli M, Battaglia M, Magnani CF, Hauben E, Roncarolo M-G. Differentiation of type 1 T regulatory cells (Tr1) by tolerogenic DC-10 requires the IL-10-dependent ILT4/HLA-G pathway. Blood. 2010;116:935–944. doi: 10.1182/blood-2009-07-234872. PubMed DOI

Stiff A, Trikha P, Mundy-Bosse BL, McMichael EL, Mace TA, Benner B, Kendra K, Campbell A, Gautam S, Abood D, Landi I, Hsu V, Duggan MC, Wesolowski R, Old M, Howard JH, Yu L, Stasik N, Olencki T, et al. Nitric oxide production by myeloid derived suppressor cells plays a role in impairing Fc receptor-mediated natural killer cell function. Clin Cancer Res. 2018 doi: 10.1158/1078-0432.CCR-17-0691. PubMed DOI PMC

Mao Y, Sarhan D, Steven A, Seliger B, Kiessling R, Lundqvist A. Inhibition of tumor-derived prostaglandin-e2 blocks the induction of myeloid-derived suppressor cells and recovers natural killer cell activity. Clin Cancer Res. 2014;20:4096–4106. doi: 10.1158/1078-0432.CCR-14-0635. PubMed DOI

Goh CC, Roggerson KM, Lee H-C, Golden-Mason L, Rosen HR, Hahn YS. Hepatitis C virus-induced myeloid-derived suppressor cells suppress NK Cell IFN-γ production by altering cellular metabolism via arginase-1. J Immunol. 2016;196:2283–2292. doi: 10.4049/jimmunol.1501881. PubMed DOI PMC

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