ABSTRACT Myeloid-derived suppressor cells (MDSCs) are pathologically activated neutrophils and monocytes with potent immunosuppressive activity. They are implicated in the regulation of

immune responses in many pathological conditions and are closely associated with poor clinical outcomes in cancer. Recent studies have indicated key distinctions between MDSCs and classical

neutrophils and monocytes, and, in this Review, we discuss new data on the major genomic and metabolic characteristics of MDSCs. We explain how these characteristics shape MDSC function and

could facilitate therapeutic targeting of these cells, particularly in cancer and in autoimmune diseases. Additionally, we briefly discuss emerging data on MDSC involvement in pregnancy,

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SIMILAR CONTENT BEING VIEWED BY OTHERS MYELOID-DERIVED SUPPRESSOR CELLS AS IMMUNOSUPPRESSIVE REGULATORS AND THERAPEUTIC TARGETS IN CANCER Article Open access 07 October 2021 NEUTROPHILS AND

POLYMORPHONUCLEAR MYELOID-DERIVED SUPPRESSOR CELLS: AN EMERGING BATTLEGROUND IN CANCER THERAPY Article Open access 03 May 2022 MYELOID-DERIVED SUPPRESSOR CELLS IN CANCER AND CANCER THERAPY

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Central  Google Scholar  Download references ACKNOWLEDGEMENTS The authors thank S. Gabrilovich, Rutgers New Jersey Medical School, for help with editing the manuscript. AUTHOR INFORMATION

Author notes * These authors contributed equally: Filippo Veglia, Emilio Sanseviero. AUTHORS AND AFFILIATIONS * H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA Filippo

Veglia * Wistar Institute, Philadelphia, PA, USA Emilio Sanseviero * AstraZeneca, Gaithersburg, MD, USA Dmitry I. Gabrilovich Authors * Filippo Veglia View author publications You can also

search for this author inPubMed Google Scholar * Emilio Sanseviero View author publications You can also search for this author inPubMed Google Scholar * Dmitry I. Gabrilovich View author

publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS The authors contributed equally to all aspects of the article. CORRESPONDING AUTHOR Correspondence to

Dmitry I. Gabrilovich. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION PEER REVIEW INFORMATION _Nature Reviews Immunology_ thanks

the anonymous, reviewers for their contribution to the peer review of this work. PUBLISHER’S NOTE Springer Nature remains neutral with regard to jurisdictional claims in published maps and

institutional affiliations. GLOSSARY * Monocyte-like precursor of granulocytes Recently identified population of monocytic precursors of granulocytes (primarily polymorphonuclear

myeloid-derived suppressor cells (MDSCs)) accumulated in tumour-bearing hosts. * S100A8/A9 Heterodimer, calcium binding pro-inflammatory protein that presents in neutrophils and monocytes

and greatly accumulates in MDSCs; it is considered as one of the hallmarks of these cells. * M1/M2 polarized macrophages ‘M1’ and ‘M2’ are classifications historically used to define

macrophages activated in vitro as pro-inflammatory (when ‘classically’ activated with IFNγ and lipopolysaccharides) or anti-inflammatory (when ‘alternatively’ activated with IL-4 or IL-10),

respectively. However, in vivo macrophages are highly specialized, transcriptomically dynamic and extremely heterogeneous with regards to their phenotypes and functions, which are

continuously shaped by their tissue microenvironment. Therefore, the M1 or M2 classification is too simplistic to explain the true nature of in vivo macrophages, although these terms are

still often used to indicate whether the macrophages in question are more pro-inflammatory or anti-inflammatory. * Methylglyoxal CH3C(O)CHO is a reduced derivative of pyruvic acid involved

in the formation of advanced glycation end products. * STING Stimulator of interferon genes (STING) induces type I interferon production. * Lactoferrin A globular glycoprotein from the

transferrin family widely expressed in various secretory fluids such as milk, saliva, tears and nasal secretions. RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS

ARTICLE Veglia, F., Sanseviero, E. & Gabrilovich, D.I. Myeloid-derived suppressor cells in the era of increasing myeloid cell diversity. _Nat Rev Immunol_ 21, 485–498 (2021).

https://doi.org/10.1038/s41577-020-00490-y Download citation * Accepted: 14 December 2020 * Published: 01 February 2021 * Issue Date: August 2021 * DOI:

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