{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T15:43:17Z","timestamp":1782402197650,"version":"3.54.5"},"reference-count":98,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2022,9,27]],"date-time":"2022-09-27T00:00:00Z","timestamp":1664236800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Orthodontically induced inflammatory root resorption (OIIRR) is considered an undesired and inevitable complication induced by orthodontic forces. This inflammatory mechanism is regulated by immune cells that precede orthodontic tooth movement (OTM) and can influence the severity of OIIRR. The process of OIIRR is based on an immune response. On some occasions, the immune system attacks the dentition by inflammatory processes during orthodontic treatment. Studies on the involvement of the PD-1\/PD-L1 immune checkpoint have demonstrated its role in evading immune responses, aiming to identify possible novel therapeutic approaches for periodontitis. In the field of orthodontics, the important question arises of whether PD-L1 has a role in the development of OIIRR to amplify the amount of resorption. We hypothesize that blocking of the PD-L1 immune checkpoint could be a suitable procedure to reduce the process of OIIRR during orthodontic tooth movement. This review attempts to shed light on the regulation of immune mechanisms and inflammatory responses that could influence the pathogenesis of OIIRR and to acquire knowledge about the role of PD-L1 in the immunomodulation involved in OIIRR. Possible clinical outcomes will be discussed in relation to PD-L1 expression and immunologic changes throughout the resorption process.<\/jats:p>","DOI":"10.3390\/ijms231911405","type":"journal-article","created":{"date-parts":[[2022,9,27]],"date-time":"2022-09-27T23:12:12Z","timestamp":1664320332000},"page":"11405","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["PD-L1, a Potential Immunomodulator Linking Immunology and Orthodontically Induced Inflammatory Root Resorption (OIIRR): Friend or Foe?"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3021-075X","authenticated-orcid":false,"given":"Jiawen","family":"Yong","sequence":"first","affiliation":[{"name":"Department of Orthodontics, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"},{"name":"Department of Periodontology, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"},{"name":"Stomatology Hospital, School of Stomatology, Zhejiang University School of Medicine, Zhejiang Provincial Clinical Research Center for Oral Diseases, Key Laboratory of Oral Biomedical Research of Zhejiang Province, Cancer Center of Zhejiang University, Hangzhou 310003, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine","family":"Gr\u00f6ger","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia","family":"von Bremen","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0495-6926","authenticated-orcid":false,"given":"Joerg","family":"Meyle","sequence":"additional","affiliation":[{"name":"Department of Periodontology, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine","family":"Ruf","sequence":"additional","affiliation":[{"name":"Department of Orthodontics, Faculty of Medicine, Justus Liebig University Giessen, 35392 Giessen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,9,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"54","DOI":"10.31083\/j.fbl2702054","article-title":"MAPK and \u03b2-Catenin signaling: Implication and interplay in orthodontic tooth movement","volume":"27","author":"Yong","year":"2022","journal-title":"Front. Biosci. (Landmark Ed.)"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"430","DOI":"10.1007\/s00056-014-0237-5","article-title":"Compression of human primary cementoblasts leads to apoptosis: A possible cause of dental root resorption?","volume":"75","author":"Diercke","year":"2014","journal-title":"J. Orofac. Orthop."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"645005","DOI":"10.3389\/fcell.2021.645005","article-title":"Adiponectin as Well as Compressive Forces Regulate in vitro beta-Catenin Expression on Cementoblasts via Mitogen-Activated Protein Kinase Signaling Activation","volume":"9","author":"Yong","year":"2021","journal-title":"Front. Cell Dev. Biol."},{"key":"ref_4","first-page":"175","article-title":"Orthodontically induced inflammatory root resorption. Part I: The basic science aspects","volume":"72","author":"Brezniak","year":"2002","journal-title":"Angle Orthod."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"448","DOI":"10.1016\/j.ajodo.2007.06.012","article-title":"Identification of orthodontic patients at risk of severe apical root resorption","volume":"135","author":"Artun","year":"2009","journal-title":"Am. J. Orthod. Dentofac. Orthop."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"340","DOI":"10.4103\/0970-9290.44539","article-title":"Immunology of root resorption: A literature review","volume":"19","author":"Silva","year":"2008","journal-title":"Indian J. Dent. Res."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1007\/s00441-003-0753-x","article-title":"Sympathectomy causes increased root resorption after orthodontic tooth movement in rats: Immunohistochemical study","volume":"313","author":"Haug","year":"2003","journal-title":"Cell Tissue Res."},{"key":"ref_8","first-page":"100","article-title":"CD40-CD40L expression during orthodontic tooth movement in rats","volume":"74","author":"Alhashimi","year":"2004","journal-title":"Angle Orthod."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1463","DOI":"10.1177\/0022034515595003","article-title":"T Cells Are Required for Orthodontic Tooth Movement","volume":"94","author":"Yan","year":"2015","journal-title":"J. Dent. Res."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"104884","DOI":"10.1016\/j.archoralbio.2020.104884","article-title":"Global gene expression profile of periodontal ligament cells submitted to mechanical loading: A systematic review","volume":"118","author":"Spitz","year":"2020","journal-title":"Arch. Oral. Biol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1177\/0022034516677539","article-title":"Cellular and Molecular Pathways Leading to External Root Resorption","volume":"96","author":"Hartsfield","year":"2017","journal-title":"J. Dent. Res."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"63","DOI":"10.1016\/j.jdsr.2016.04.002","article-title":"Histology of human cementum: Its structure, function, and development","volume":"52","author":"Yamamoto","year":"2016","journal-title":"Jpn. Dent. Sci. Rev."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"585346","DOI":"10.3389\/fphar.2020.585346","article-title":"Adiponectin Interacts In-Vitro with Cementoblasts Influencing Cell Migration, Proliferation and Cementogenesis Partly Through the MAPK Signaling Pathway","volume":"11","author":"Yong","year":"2020","journal-title":"Front. Pharmacol."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"8172","DOI":"10.1038\/s41598-020-65089-8","article-title":"Immunorthodontics: In vivo gene expression of orthodontic tooth movement","volume":"10","author":"Klein","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"651","DOI":"10.1002\/dvdy.10404","article-title":"Role of Hertwig\u2019s epithelial root sheath cells in tooth root development","volume":"228","author":"Oishi","year":"2003","journal-title":"Dev. Dyn."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"218","DOI":"10.1111\/j.1600-9657.2005.00296.x","article-title":"Humoral immune response of patients with dental trauma and consequent replacement resorption","volume":"21","author":"Hidalgo","year":"2005","journal-title":"Dent. Traumatol."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1016\/j.neo.2017.02.006","article-title":"Identifying Regulatory Posttranslational Modifications of PD-L1: A Focus on Monoubiquitinaton","volume":"19","author":"Horita","year":"2017","journal-title":"Neoplasia"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"1027","DOI":"10.1084\/jem.192.7.1027","article-title":"Engagement of the PD-1 immunoinhibitory receptor by a novel B7 family member leads to negative regulation of lymphocyte activation","volume":"192","author":"Freeman","year":"2000","journal-title":"J. Exp. Med."},{"key":"ref_19","first-page":"5399","article-title":"PD-L1 expression levels on tumor cells affect their immunosuppressive activity","volume":"18","author":"Zheng","year":"2019","journal-title":"Oncol. Lett."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"99","DOI":"10.1007\/s12253-016-0100-7","article-title":"Oral Squamous Carcinoma Cells Express B7-H1 and B7-DC Receptors in Vivo","volume":"23","author":"Groeger","year":"2017","journal-title":"Pathol. Oncol. Res."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"172","DOI":"10.1111\/omi.12332","article-title":"Porphyromonas gingivalis induced up-regulation of PD-L1 in colon carcinoma cells","volume":"36","author":"Groeger","year":"2021","journal-title":"Mol. Oral. Microbiol."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"935806","DOI":"10.3389\/fcimb.2022.935806","article-title":"PD-L1 Up-Regulation in Prostate Cancer Cells by Porphyromonas gingivalis","volume":"12","author":"Groeger","year":"2022","journal-title":"Front. Cell Infect. Microbiol."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"895","DOI":"10.1084\/jem.20160801","article-title":"PD-L1 on tumor cells is sufficient for immune evasion in immunogenic tumors and inhibits CD8 T cell cytotoxicity","volume":"214","author":"Juneja","year":"2017","journal-title":"J. Exp. Med."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1016\/j.jdsr.2020.04.002","article-title":"The implication of the PD-1\/PD-L1 checkpoint in chronic periodontitis suggests novel therapeutic opportunities with natural products","volume":"56","author":"Bailly","year":"2020","journal-title":"Jpn. Dent. Sci. Rev."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"350","DOI":"10.1093\/ejo\/cjr018","article-title":"Association between root resorption incident to orthodontic treatment and treatment factors","volume":"34","author":"Motokawa","year":"2012","journal-title":"Eur. J. Orthod."},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Yamaguchi, M., and Fukasawa, S. (2021). Is Inflammation a Friend or Foe for Orthodontic Treatment?: Inflammation in Orthodontically Induced Inflammatory Root Resorption and Accelerating Tooth Movement. Int. J. Mol. Sci., 22.","DOI":"10.3390\/ijms22052388"},{"key":"ref_27","first-page":"6767","article-title":"Physiological Role of Immune System Elements in Orthodontic Treatment","volume":"20","author":"Mohammed","year":"2020","journal-title":"Med.-Leg. Update"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1111\/j.1365-2591.1985.tb00426.x","article-title":"General morphological aspects of resorption of teeth and alveolar bone","volume":"18","author":"Hammarstrom","year":"1985","journal-title":"Int. Endod. J."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"71","DOI":"10.1111\/adj.12483","article-title":"Root Resorption with Orthodontic Mechanics: Pertinent Areas Revisited","volume":"62","author":"Krishnan","year":"2017","journal-title":"Aust. Dent. J."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1908","DOI":"10.1177\/00220345920710121001","article-title":"Histomorphometric study of the periodontal vasculature of the rat incisor","volume":"71","author":"Blaushild","year":"1992","journal-title":"J. Dent. Res."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1111\/iej.12450","article-title":"A novel multimodular methodology to investigate external cervical tooth resorption","volume":"49","author":"Mavridou","year":"2016","journal-title":"Int. Endod. J."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Galler, K.M., Gratz, E.M., Widbiller, M., Buchalla, W., and Knuttel, H. (2021). Pathophysiological mechanisms of root resorption after dental trauma: A systematic scoping review. BMC Oral. Health, 21.","DOI":"10.1186\/s12903-021-01510-6"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"249","DOI":"10.1093\/ejo\/15.4.249","article-title":"The initial phase of orthodontic root resorption incident to local compression of the periodontal ligament","volume":"15","author":"Brudvik","year":"1993","journal-title":"Eur. J. Orthod."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"21","DOI":"10.1093\/ejo\/14.1.21","article-title":"The effects of horizontal tooth loading on the circulation and width of the periodontal ligament\u2014An experimental study on beagle dogs","volume":"14","author":"Goz","year":"1992","journal-title":"Eur. J. Orthod."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1093\/ejo\/18.1.11","article-title":"The hyaline zone and associated root surface changes in experimental orthodontics in rats: A light and scanning electron microscope study","volume":"18","author":"Hellsing","year":"1996","journal-title":"Eur. J. Orthod."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"191","DOI":"10.4161\/cam.27840","article-title":"Podosome organization drives osteoclast-mediated bone resorption","volume":"8","author":"Georgess","year":"2014","journal-title":"Cell Adhes. Migr."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"346","DOI":"10.1093\/ejo\/cjp020","article-title":"Dynamics of orthodontic root resorption and repair in human premolars: A light microscopy study","volume":"31","author":"Winter","year":"2009","journal-title":"Eur. J. Orthod."},{"key":"ref_38","first-page":"180","article-title":"Orthodontically induced inflammatory root resorption. Part II: The clinical aspects","volume":"72","author":"Brezniak","year":"2002","journal-title":"Ang. Orthod."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"e495","DOI":"10.1016\/j.ajodo.2010.01.036","article-title":"Physical properties of root cementum: Part 18. The extent of root resorption after the application of light and heavy controlled rotational orthodontic forces for 4 weeks: A microcomputed tomography study","volume":"139","author":"Wu","year":"2011","journal-title":"Am. J. Orthod. Dentofac. Orthop."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1111\/j.1601-0825.2010.01718.x","article-title":"Osteoclasts and odontoclasts: Signaling pathways to development and disease","volume":"17","author":"Wang","year":"2011","journal-title":"Oral. Dis."},{"key":"ref_41","first-page":"826","article-title":"Molecular mechanisms in dental hard tissue mineralization","volume":"1","author":"Limeback","year":"1991","journal-title":"Curr. Opin. Dent."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"228","DOI":"10.4103\/0973-029X.119736","article-title":"An insight into the regulatory mechanisms of cells involved in resorption of dental hard tissues","volume":"17","author":"Kamat","year":"2013","journal-title":"J. Oral. Maxillofac. Pathol."},{"key":"ref_43","unstructured":"Kumar, G. (2015). Orban\u2019s Oral Histology & Embryology-E-BOOK, Elsevier Health Sciences."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"11","DOI":"10.1177\/00220345211016285","article-title":"Immune Changes Induced by Orthodontic Forces: A Critical Review","volume":"101","author":"Chaushu","year":"2022","journal-title":"J. Dent. Res."},{"key":"ref_45","first-page":"9","article-title":"Tooth resorption","volume":"30","author":"Ne","year":"1999","journal-title":"Quintessence Int."},{"key":"ref_46","unstructured":"Nanci, A. (2007). Physiologic tooth movement: Eruption and shedding. Ten Cate\u2019s Oral Histology\u2014Development, Structure, and Function, Elsevier."},{"key":"ref_47","unstructured":"Hidalgo, M. (2001). Study About the Immunogenic Potential of Dentin: A Contribution to the Etiopathogeny of Root Resorption. [Ph.D. Thesis, Faculdade de Odontologia de Bauru, Universidade de S\u00e3o Paulo]."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"435","DOI":"10.1093\/ejo\/18.1.435","article-title":"Healing of the root surface-associated periodontium: An immunohistochemical study of orthodontic root resorption in man","volume":"18","author":"Sismanidou","year":"1996","journal-title":"Eur. J. Orthod."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1093\/ejo\/17.3.177","article-title":"Transition and determinants of orthodontic root resorption-repair sequence","volume":"17","author":"Brudvik","year":"1995","journal-title":"Eur. J. Orthod."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"189","DOI":"10.1093\/ejo\/17.3.189","article-title":"The repair of orthodontic root resorption: An ultrastructural study","volume":"17","author":"Brudvik","year":"1995","journal-title":"Eur. J. Orthod."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1093\/ejo\/cjn012","article-title":"Cellular and extracellular factors in early root resorption repair in the rat","volume":"30","author":"Jager","year":"2008","journal-title":"Eur. J. Orthod."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"462","DOI":"10.1016\/j.ajodo.2009.06.021","article-title":"Root resorption associated with orthodontic tooth movement: A systematic review","volume":"137","author":"Weltman","year":"2010","journal-title":"Am. J. Orthod. Dentofac. Orthop."},{"key":"ref_53","first-page":"143.e15","article-title":"Evaluation of root resorption after open bite treatment with and without extractions","volume":"132","author":"Beltrao","year":"2007","journal-title":"Am. J. Orthod. Dentofac. Orthop."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"731","DOI":"10.1177\/0022034520984774","article-title":"\u03b3\u03b4T Cells Are Essential for Orthodontic Tooth Movement","volume":"100","author":"Wald","year":"2021","journal-title":"J. Dent. Res."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"1352","DOI":"10.1016\/j.ajpath.2013.06.034","article-title":"Phenotypic transitions of macrophages orchestrate tissue repair","volume":"183","author":"Novak","year":"2013","journal-title":"Am. J. Pathol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"1286","DOI":"10.1177\/0022034515589714","article-title":"M1-like Macrophage Polarization Promotes Orthodontic Tooth Movement","volume":"94","author":"He","year":"2015","journal-title":"J. Dent. Res."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"129","DOI":"10.1177\/0022034514553817","article-title":"Enhanced M1\/M2 macrophage ratio promotes orthodontic root resorption","volume":"94","author":"He","year":"2015","journal-title":"J. Dent. Res."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1111\/j.1600-0722.1997.tb00178.x","article-title":"Immunocompetent cells in rat periodontal ligament and their recruitment incident to experimental orthodontic tooth movement","volume":"105","author":"Kvinnsland","year":"1997","journal-title":"Eur. J. Oral. Sci."},{"key":"ref_59","first-page":"2814015","article-title":"Effects of Compressive and Tensile Strain on Macrophages during Simulated Orthodontic Tooth Movement","volume":"2020","author":"Schroder","year":"2020","journal-title":"Mediat. Inflamm."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.1053\/j.gastro.2009.12.041","article-title":"In vitro-derived alternatively activated macrophages reduce colonic inflammation in mice","volume":"138","author":"Hunter","year":"2010","journal-title":"Gastroenterology"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"1447","DOI":"10.1177\/00220345820610121501","article-title":"Behavior of mast cells in periodontal ligament associated with experimental tooth movement in rats","volume":"61","author":"Yamasaki","year":"1982","journal-title":"J. Dent. Res."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"15327","DOI":"10.1096\/fj.202001078R","article-title":"T cells participate in bone remodeling during the rapid palatal expansion","volume":"34","author":"Li","year":"2020","journal-title":"FASEB J."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"2891","DOI":"10.1002\/jcb.23205","article-title":"Human periodontal ligament fibroblasts stimulate osteoclastogenesis in response to compression force through TNF-alpha-mediated activation of CD4+ T cells","volume":"112","author":"Kook","year":"2011","journal-title":"J. Cell. Biochem."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"190","DOI":"10.3389\/fimmu.2015.00190","article-title":"Editorial: Secretion of cytokines and chemokines by innate immune cells","volume":"6","author":"Lacy","year":"2015","journal-title":"Front. Immunol."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"e5","DOI":"10.1038\/ijos.2017.45","article-title":"Interleukin-1beta induces human cementoblasts to support osteoclastogenesis","volume":"9","author":"Huynh","year":"2017","journal-title":"Int. J. Oral. Sci."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"257","DOI":"10.1053\/j.sodo.2012.06.004","article-title":"Inflammation and Tooth Movement: The Role of Cytokines, Chemokines, and Growth Factors","volume":"18","author":"Andrade","year":"2012","journal-title":"Semin. Orthod."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"153","DOI":"10.1016\/j.ajodo.2011.07.019","article-title":"Role of CCR2 in orthodontic tooth movement","volume":"141","author":"Taddei","year":"2012","journal-title":"Am. J. Orthod. Dentofac. Orthop."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1053\/j.sodo.2015.06.001","article-title":"Biological principles behind accelerated tooth movement","volume":"21","author":"Alansari","year":"2015","journal-title":"Semin. Orthod."},{"key":"ref_69","doi-asserted-by":"crossref","unstructured":"Yong, J., Groeger, S., von Bremen, J., and Ruf, S. (2022). Ciliary Neurotrophic Factor (CNTF) and Its Receptors Signal Regulate Cementoblasts Apoptosis through a Mechanism of ERK1\/2 and Caspases Signaling. Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms23158335"},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1016\/j.coi.2007.04.012","article-title":"PD-1 and its ligands in T-cell immunity","volume":"19","author":"Keir","year":"2007","journal-title":"Curr. Opin. Immunol."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"1302","DOI":"10.1016\/j.imbio.2011.05.005","article-title":"B7-H1 and B7-DC receptors of oral squamous carcinoma cells are upregulated by Porphyromonas gingivalis","volume":"216","author":"Groeger","year":"2011","journal-title":"Immunobiology"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1016\/j.imbio.2016.10.011","article-title":"Induction of B7-H1 receptor by bacterial cells fractions of Porphyromonas gingivalis on human oral epithelial cells: B7-H1 induction by Porphyromonas gingivalis fractions","volume":"222","author":"Groeger","year":"2017","journal-title":"Immunobiology"},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"650","DOI":"10.1038\/mi.2016.89","article-title":"Unique B7-H1 expression on masticatory mucosae in the oral cavity and trans-coinhibition by B7-H1-expressing keratinocytes regulating CD4(+) T cell-mediated mucosal tissue inflammation","volume":"10","author":"Kang","year":"2017","journal-title":"Mucosal Immunol."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"690","DOI":"10.1158\/2326-6066.CIR-13-0224","article-title":"Programmed cell death ligand 1 expression in osteosarcoma","volume":"2","author":"Shen","year":"2014","journal-title":"Cancer Immunol. Res."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"3603","DOI":"10.1172\/JCI133334","article-title":"PD-1 blockade inhibits osteoclast formation and murine bone cancer pain","volume":"130","author":"Wang","year":"2020","journal-title":"J. Clin. Investig."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"2423","DOI":"10.3892\/mmr.2016.4824","article-title":"Expression of programmed death 1 ligand 1 on periodontal tissue cells as a possible protective feedback mechanism against periodontal tissue destruction","volume":"13","author":"Zhang","year":"2016","journal-title":"Mol. Med. Rep."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"105161","DOI":"10.1016\/j.archoralbio.2021.105161","article-title":"LPS Stimulates Gingival Fibroblasts to Express PD-L1 via the p38 Pathway under Periodontal Inflammatory Conditions","volume":"129","author":"Zhou","year":"2021","journal-title":"Arch. Oral. Biol."},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1186\/s13045-016-0277-y","article-title":"Current status and perspectives in translational biomarker research for PD-1\/PD-L1 immune checkpoint blockade therapy","volume":"9","author":"Ma","year":"2016","journal-title":"J. Hematol. Oncol."},{"key":"ref_79","first-page":"3635","article-title":"B7-H1 Receptor Induced T-Helper Cell Differentiation in vitro","volume":"111","author":"Meyle","year":"2008","journal-title":"Blood"},{"key":"ref_80","first-page":"216","article-title":"Expression of programmed death-1 and programmed death ligand-1 in the peripheral T-lymphocytes from patients with chronic periodontitis","volume":"49","author":"Zhu","year":"2014","journal-title":"Zhonghua Kou Qiang Yi Xue Za Zhi Zhonghua Kouqiang Yixue Zazhi Chin. J. Stomatol."},{"key":"ref_81","first-page":"3","article-title":"Programmed death 1 (PD-1) and PD-1 ligand (PD-L1) expression in chronic apical periodontitis","volume":"4","author":"Delgado","year":"2019","journal-title":"Eur. Endod. J."},{"key":"ref_82","doi-asserted-by":"crossref","unstructured":"la Rosa-Ruiz, D., del Pilar, M., \u00c1lvarez-P\u00e9rez, M.A., Cort\u00e9s-Morales, V.A., Monroy-Garc\u00eda, A., Mayani, H., Fragoso-Gonz\u00e1lez, G., Caballero-Chac\u00f3n, S., Diaz, D., and Candanedo-Gonz\u00e1lez, F. (2019). Mesenchymal stem\/stromal cells derived from dental tissues: A comparative in vitro evaluation of their immunoregulatory properties against T cells. Cells, 8.","DOI":"10.3390\/cells8121491"},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"221","DOI":"10.1016\/j.oraloncology.2014.11.014","article-title":"Intrinsic and extrinsic control of expression of the immunoregulatory molecule PD-L1 in epithelial cells and squamous cell carcinoma","volume":"51","author":"Ritprajak","year":"2015","journal-title":"Oral. Oncol."},{"key":"ref_84","doi-asserted-by":"crossref","unstructured":"Yong, J., Gr\u00f6ger, S., Meyle, J., and Ruf, S. (2022). Immunorthodontics: Role of HIF-1\u03b1 in the Regulation of (Peptidoglycan-Induced) PD-L1 Expression in Cementoblasts under Compressive Force. Int. J. Mol. Sci., 23.","DOI":"10.3390\/ijms23136977"},{"key":"ref_85","doi-asserted-by":"crossref","unstructured":"Yong, J., Gr\u00f6ger, S., von Bremen, J., Meyle, J., and Ruf, S. (2022). Immunorthodontics: PD-L1, a Novel Immunomodulator in Cementoblasts, Is Regulated by HIF-1\u03b1 under Hypoxia. Cells, 11.","DOI":"10.3390\/cells11152350"},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"396","DOI":"10.1002\/ijc.30077","article-title":"PD-L1 expression is regulated by hypoxia inducible factor in clear cell renal cell carcinoma","volume":"139","author":"Ruf","year":"2016","journal-title":"Int. J. Cancer"},{"key":"ref_87","doi-asserted-by":"crossref","unstructured":"Shelby, A., Pendleton, C., Thayer, E., Johnson, G.K., Xie, X.J., and Brogden, K.A. (2020). PD-L1 correlates with chemokines and cytokines in gingival crevicular fluid from healthy and diseased sites in subjects with periodontitis. BMC Res. Notes, 13.","DOI":"10.1186\/s13104-020-05376-9"},{"key":"ref_88","doi-asserted-by":"crossref","first-page":"146","DOI":"10.1002\/JPER.21-0017","article-title":"Overexpression of PD-L1 in gingival basal keratinocytes reduces periodontal inflammation in a ligature-induced periodontitis model","volume":"93","author":"Wongtim","year":"2021","journal-title":"J. Periodontol."},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"1919082","DOI":"10.1155\/2019\/1919082","article-title":"Beyond T Cells: Understanding the Role of PD-1\/PD-L1 in Tumor-Associated Macrophages","volume":"2019","author":"Lu","year":"2019","journal-title":"J. Immunol. Res."},{"key":"ref_90","doi-asserted-by":"crossref","unstructured":"Seliger, B. (2019). Basis of PD1\/PD-L1 Therapies. J. Clin. Med., 8.","DOI":"10.3390\/jcm8122168"},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"275","DOI":"10.1038\/nrc.2016.36","article-title":"Mechanism-driven biomarkers to guide immune checkpoint blockade in cancer therapy","volume":"16","author":"Topalian","year":"2016","journal-title":"Nat. Rev. Cancer"},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1016\/j.coi.2011.12.009","article-title":"Targeting the PD-1\/B7-H1(PD-L1) pathway to activate anti-tumor immunity","volume":"24","author":"Topalian","year":"2012","journal-title":"Curr. Opin. Immunol."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"225","DOI":"10.14740\/jocmr3750","article-title":"Adverse Effects of Immune Checkpoint Inhibitors (Programmed Death-1 Inhibitors and Cytotoxic T-Lymphocyte-Associated Protein-4 Inhibitors): Results of a Retrospective Study","volume":"11","author":"Bajwa","year":"2019","journal-title":"J. Clin. Med. Res."},{"key":"ref_94","first-page":"17","article-title":"Anti PD-1 immunotherapy related interstitial lung disease presenting as respiratory failure\u2014A review with case series","volume":"26","author":"Akella","year":"2019","journal-title":"Respir. Med. Case Rep."},{"key":"ref_95","first-page":"3406437","article-title":"Anti-PD-1 Therapy-Associated Perforating Colitis","volume":"2018","author":"Celli","year":"2018","journal-title":"Case Rep. Gastrointest. Med."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"92.e1","DOI":"10.1016\/j.cjca.2017.09.025","article-title":"Immune Checkpoint Inhibitor-Associated Myocarditis: A New Challenge for Cardiologists","volume":"34","author":"Frigeri","year":"2018","journal-title":"Can. J. Cardiol."},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"363","DOI":"10.1530\/EJE-19-0291","article-title":"Immune checkpoint inhibitors and type 1 diabetes mellitus: A case report and systematic review","volume":"181","author":"Pen","year":"2019","journal-title":"Eur. J. Endocrinol."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"e464","DOI":"10.1111\/jdv.14284","article-title":"Oral lichenoid reactions associated with anti-PD-1\/PD-L1 therapies: Clinicopathological findings","volume":"31","author":"Sibaud","year":"2017","journal-title":"J. Eur. Acad. Dermatol. 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