{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,16]],"date-time":"2026-07-16T15:22:34Z","timestamp":1784215354156,"version":"3.55.0"},"reference-count":131,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2022,12,13]],"date-time":"2022-12-13T00:00:00Z","timestamp":1670889600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Immunol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Recovery from coronavirus disease 2019 (COVID-19) can be impaired by the persistence of symptoms or new-onset health complications, commonly referred to as Long COVID. In a subset of patients, Long COVID is associated with immune system perturbations of unknown etiology, which could be related to compromised immunoregulatory mechanisms.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>The objective of this scoping review was to summarize the existing literature regarding the frequency and functionality of Tregs in convalescent COVID-19 patients and to explore indications for their potential involvement in the development of Long COVID<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Design<\/jats:title>\n                    <jats:p>\n                      A systematic search of studies investigating Tregs during COVID-19 convalescence was conducted on MEDLINE (\n                      <jats:italic>via<\/jats:italic>\n                      Pubmed) and Web of Science.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>The literature search yielded 17 relevant studies, of which three included a distinct cohort of patients with Long COVID. The reviewed studies suggest that the Treg population of COVID-19 patients can reconstitute quantitatively and functionally during recovery. However, the comparison between recovered and seronegative controls revealed that an infection-induced dysregulation of the Treg compartment can be sustained for at least several months. The small number of studies investigating Tregs in Long COVID allowed no firm conclusions to be drawn about their involvement in the syndrome\u2019s etiology. Yet, even almost one year post-infection Long COVID patients exhibit significantly altered proportions of Tregs within the CD4+ T cell population.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Persistent alterations in cell frequency in Long COVID patients indicate that Treg dysregulation might be linked to immune system-associated sequelae. Future studies should aim to address the association of Treg adaptations with different symptom clusters and blood parameters beyond the sole quantification of cell frequencies while adhering to consensualized phenotyping strategies.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fimmu.2022.1070994","type":"journal-article","created":{"date-parts":[[2022,12,13]],"date-time":"2022-12-13T01:48:05Z","timestamp":1670896085000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":38,"title":["A scoping review of regulatory T cell dynamics in convalescent COVID-19 patients \u2013 indications for their potential involvement in the development of Long COVID?"],"prefix":"10.3389","volume":"13","author":[{"given":"Simon","family":"Haunhorst","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wilhelm","family":"Bloch","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florian","family":"Javelle","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karsten","family":"Kr\u00fcger","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sabine","family":"Baumgart","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sebastian","family":"Drube","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina","family":"Lemh\u00f6fer","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Philipp","family":"Reuken","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andreas","family":"Stallmach","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"M\u00fcller","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christina E.","family":"Zielinski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mathias W.","family":"Pletz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Holger H. W.","family":"Gabriel","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Christian","family":"Puta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2022,12,13]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"NEJMoa2002032","DOI":"10.1056\/nejmoa2002032","article-title":"Clinical characteristics of coronavirus disease 2019 in China","volume":"382","author":"Guan","year":"2020","journal-title":"New Engl J Med"},{"key":"B2","doi-asserted-by":"publisher","first-page":"497","DOI":"10.1016\/s0140-6736(20)30183-5","article-title":"Clinical features of patients infected with 2019 novel coronavirus in wuhan, China","volume":"395","author":"Huang","year":"2020","journal-title":"Lancet Lond Engl"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1038\/s41591-020-0968-3","article-title":"Extrapulmonary manifestations of COVID-19","volume":"26","author":"Gupta","year":"2020","journal-title":"Nat Med"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1080\/00325481.2020.1823094","article-title":"Multisystem effects of COVID-19: A concise review for practitioners","volume":"133","author":"White-Dzuro","year":"2020","journal-title":"Postgrad Med"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1056\/nejmoa2015432","article-title":"Pulmonary vascular endothelialitis, thrombosis, and angiogenesis in covid-19","volume":"383","author":"Ackermann","year":"2020","journal-title":"New Engl J Med"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1002\/art.41285","article-title":"On the alert for cytokine storm: Immunopathology in COVID-19","volume":"72","author":"Henderson","year":"2020","journal-title":"Arthritis Rheumatol Hoboken N J"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.00827","article-title":"Reduction and functional exhaustion of T cells in patients with coronavirus disease 2019 (COVID-19)","volume":"11","author":"Diao","year":"2020","journal-title":"Front Immunol"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1016\/j.cca.2020.05.019","article-title":"Decreased T cell populations contribute to the increased severity of COVID-19","volume":"508","author":"Liu","year":"2020","journal-title":"Clin Chimica Acta Int J Clin Chem"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1111\/cts.12805","article-title":"Clinical and autoimmune characteristics of severe and critical cases of COVID-19","volume":"13","author":"Zhou","year":"2020","journal-title":"Clin Transl Sci"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1016\/s0140-6736(22)01214-4","article-title":"Persistence of somatic symptoms after COVID-19 in the Netherlands: an observational cohort study","volume":"400","author":"Ballering","year":"2022","journal-title":"Lancet"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1016\/s1473-3099(21)00703-9","article-title":"Condition WCCDWG on p-C-19. A clinical case definition of post-COVID-19 condition by a delphi consensus","volume":"22","author":"Soriano","year":"2021","journal-title":"Lancet Infect Dis"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1016\/j.eclinm.2021.100899","article-title":"Characteristics and predictors of acute and chronic post-COVID syndrome: A systematic review and meta-analysis","volume":"36","author":"Iqbal","year":"2021","journal-title":"Eclinicalmedicine"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1016\/j.eclinm.2021.101019","article-title":"Characterizing long COVID in an international cohort: 7 months of symptoms and their impact","volume":"38","author":"Davis","year":"2021","journal-title":"Eclinicalmedicine"},{"key":"B14","doi-asserted-by":"publisher","first-page":"16144","DOI":"10.1038\/s41598-021-95565-8","article-title":"More than 50 long-term effects of COVID-19: A systematic review and meta-analysis","volume":"11","author":"Lopez-Leon","year":"2021","journal-title":"Sci Rep-uk"},{"key":"B15","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1007\/s15010-022-01886-9","article-title":"Post-COVID-19 condition is not only a question of persistent symptoms: structured screening including health-related quality of life reveals two separate clusters of post-COVID","author":"Giszas","year":"2022","journal-title":"Infection"},{"key":"B16","doi-asserted-by":"publisher","first-page":"22666","DOI":"10.1038\/s41598-021-01215-4","article-title":"Long-term sequelae are highly prevalent one year after hospitalization for severe COVID-19","volume":"11","author":"Bellan","year":"2021","journal-title":"Sci Rep-uk"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1016\/s0140-6736(21)01755-4","article-title":"1-year outcomes in hospital survivors with COVID-19: A longitudinal cohort study","volume":"398","author":"Huang","year":"2021","journal-title":"Lancet"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1093\/oxfimm\/iqac006","article-title":"Long COVID: a narrative review of the clinical aftermaths of COVID-19 with a focus on the putative pathophysiology and aspects of physical activity","volume":"3","author":"Haunhorst","year":"2022","journal-title":"Oxf Open Immunol"},{"key":"B19","doi-asserted-by":"publisher","first-page":"1957","DOI":"10.1038\/s41467-022-29521-z","article-title":"Persistent COVID-19 symptoms in a community study of 606,434 people in England","volume":"13","author":"Whitaker","year":"2022","journal-title":"Nat Commun"},{"key":"B20","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1038\/s41591-022-02051-3","article-title":"Acute and postacute sequelae associated with SARS-CoV-2 reinfection","volume":"28","author":"Bowe","year":"2022","journal-title":"Nat Med"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1126\/science.abm8108","article-title":"He immunology and immunopathology of COVID-19","volume":"375","author":"Merad","year":"2022","journal-title":"Sci New York N Y"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.3390\/cells10020386","article-title":"Characterization and biomarker analyses of post-COVID-19 complications and neurological manifestations","volume":"10","author":"Sun","year":"2021","journal-title":"Cells"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1093\/infdis\/jiab490","article-title":"Markers of immune activation and inflammation in individuals with postacute sequelae of severe acute respiratory syndrome coronavirus 2 infection","volume":"11","author":"Peluso","year":"2021","journal-title":"J Infect Dis"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1016\/j.xcrm.2022.100663","article-title":"The IL-1\u03b2, IL-6, and TNF cytokine triad is associated with post-acute sequelae of COVID-19","volume":"3","author":"Schulthei\u00df","year":"2022","journal-title":"Cell Rep Med"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1016\/j.jtauto.2021.100100","article-title":"Functional autoantibodies against g-protein coupled receptors in patients with persistent long-COVID-19 symptoms","volume":"4","author":"Wallukat","year":"2021","journal-title":"J Transl Autoimmun"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1038\/s41591-022-01766-7","article-title":"Studying severe long COVID to understand post-infectious disorders beyond COVID-19","volume":"28","author":"Brodin","year":"2022","journal-title":"Nat Med"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1038\/ni904","article-title":"Foxp3 programs the development and function of CD4+CD25+ regulatory T cells","volume":"4","author":"Fontenot","year":"2003","journal-title":"Nat Immunol"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1016\/j.cell.2008.05.009","article-title":"Regulatory T cells and immune tolerance","volume":"133","author":"Sakaguchi","year":"2008","journal-title":"Cell"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1038\/nri2189","article-title":"Regulatory T cells and infection: a dangerous necessity","volume":"7","author":"Belkaid","year":"2007","journal-title":"Nat Rev Immunol"},{"key":"B30","article-title":"The effect of exercise on regulatory T cells: A systematic review of human and animal studies with future perspectives and methodological recommendations","volume":"27","author":"Proschinger","year":"2021","journal-title":"Exerc Immunol Rev"},{"key":"B31","doi-asserted-by":"publisher","first-page":"7","DOI":"10.1038\/s41577-018-0083-6","article-title":"Central CD4+ T cell tolerance: deletion versus regulatory T cell differentiation","volume":"19","author":"Klein","year":"2019","journal-title":"Nat Rev Immunol"},{"key":"B32","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1146\/annurev-immunol-042718-041717","article-title":"Regulatory T cells and human disease","volume":"38","author":"Sakaguchi","year":"2020","journal-title":"Annu Rev Immunol"},{"key":"B33","doi-asserted-by":"publisher","first-page":"490","DOI":"10.1038\/nri2785","article-title":"FOXP3+ regulatory T cells in the human immune system","volume":"10","author":"Sakaguchi","year":"2010","journal-title":"Nat Rev Immunol"},{"key":"B34","doi-asserted-by":"publisher","first-page":"90","DOI":"10.1038\/nri.2015.1","article-title":"Regulatory T cell memory","volume":"16","author":"Rosenblum","year":"2016","journal-title":"Nat Rev Immunol"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.1038\/nri2343","article-title":"How regulatory T cells work","volume":"8","author":"Vignali","year":"2008","journal-title":"Nat Rev Immunol"},{"key":"B36","doi-asserted-by":"publisher","DOI":"10.1038\/s41590-018-0120-4","article-title":"Regulatory T cells in autoimmune disease","volume":"19","author":"Dominguez-Villar","year":"2018","journal-title":"Nat Immunol"},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.1016\/j.autrev.2011.05.004","article-title":"Human FoxP3+ regulatory T cells in systemic autoimmune diseases","volume":"10","author":"Miyara","year":"2011","journal-title":"Autoimmun Rev"},{"key":"B38","doi-asserted-by":"publisher","DOI":"10.14336\/ad.2021.0709","article-title":"Regulatory T cells in COVID-19","volume":"12","author":"Wang","year":"2021","journal-title":"Aging Dis"},{"key":"B39","doi-asserted-by":"publisher","DOI":"10.7150\/ijbs.59534","article-title":"The role of CD4+FoxP3+ regulatory T cells in the immunopathogenesis of COVID-19: implications for treatment","volume":"17","author":"Wang","year":"2021","journal-title":"Int J Biol Sci"},{"key":"B40","doi-asserted-by":"publisher","DOI":"10.1002\/jmv.26891","article-title":"Toward an understanding of regulatory T cells in COVID-19: A systematic review","volume":"93","author":"Rahimzadeh","year":"2021","journal-title":"J Med Virol"},{"key":"B41","doi-asserted-by":"publisher","DOI":"10.34172\/aim.2022.22","article-title":"Regulatory T cells in immunopathogenesis and severity of COVID-19: A systematic review","volume":"25","author":"Alahyari","year":"2021","journal-title":"Arch Iran Med"},{"key":"B42","doi-asserted-by":"publisher","DOI":"10.3390\/biology10080735","article-title":"Clinical outcome prediction in COVID-19 patients by lymphocyte subsets analysis and monocytes\u2019 iTNF-\u03b1 expression","volume":"10","author":"Madonna","year":"2021","journal-title":"Biology"},{"key":"B43","doi-asserted-by":"publisher","DOI":"10.1016\/j.cyto.2021.155439","article-title":"Characterizing the immune responses of those who survived or succumbed to COVID-19: Can immunological signatures predict outcome","volume":"140","author":"Sami","year":"2021","journal-title":"Cytokine"},{"key":"B44","doi-asserted-by":"publisher","DOI":"10.1002\/jcp.30047","article-title":"Th17 and treg cells function in SARS-CoV2 patients compared with healthy controls","volume":"236","author":"Sadeghi","year":"2021","journal-title":"J Cell Physiol"},{"key":"B45","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.789735","article-title":"Regulatory T cells as predictors of clinical course in hospitalised COVID-19 patients","volume":"12","author":"Caldrer","year":"2021","journal-title":"Front Immunol"},{"key":"B46","doi-asserted-by":"publisher","DOI":"10.1002\/jmv.27401","article-title":"Duration from onset to discharge is longer in COVID-19 patients with low blood regulatory T-cell counts","volume":"94","author":"Kaya","year":"2022","journal-title":"J Med Virol"},{"key":"B47","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.589380","article-title":"T-Cell hyperactivation and paralysis in severe COVID-19 infection revealed by single-cell analysis","volume":"11","author":"Kalfaoglu","year":"2020","journal-title":"Front Immunol"},{"key":"B48","doi-asserted-by":"publisher","first-page":"74","DOI":"10.1016\/j.virol.2021.08.012","article-title":"Upregulation of FOXP3 is associated with severity of hypoxia and poor outcomes in COVID-19 patients","volume":"563","author":"Abdelhafiz","year":"2021","journal-title":"Virology"},{"key":"B49","doi-asserted-by":"publisher","DOI":"10.22037\/ghfbb.v13i4.2157","article-title":"Significant changes of CD4, FOXP3, CD25, and IL6 expression level in Iranian COVID-19 patients","volume":"13","author":"Mohebbi","year":"2020","journal-title":"Gastroenterol Hepatol Bed Bench"},{"key":"B50","doi-asserted-by":"publisher","DOI":"10.1038\/s41591-022-01810-6","article-title":"Unexplained post-acute infection syndromes","volume":"28","author":"Choutka","year":"2022","journal-title":"Nat Med"},{"key":"B51","doi-asserted-by":"publisher","DOI":"10.7326\/m18-0850","article-title":"PRISMA extension for scoping reviews (PRISMA-ScR): Checklist and explanation","volume":"169","author":"Tricco","year":"2018","journal-title":"Ann Intern Med"},{"key":"B52","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2111315118","article-title":"Profound treg perturbations correlate with COVID-19 severity","volume":"118","author":"Galv\u00e1n-Pe\u00f1a","year":"2021","journal-title":"Proc Natl Acad Sci"},{"key":"B53","doi-asserted-by":"publisher","DOI":"10.3389\/fmed.2022.828678","article-title":"Hyperinflammatory state and low T1 adaptive immune response in severe and critical acute COVID-19 patients","volume":"9","author":"Garcia-Gasalla","year":"2022","journal-title":"Front Med"},{"key":"B54","doi-asserted-by":"publisher","DOI":"10.1101\/2022.03.26.485922","article-title":"Unique molecular signatures sustained in circulating monocytes and regulatory T cells in convalescent COVID-19 patients","author":"Hoffmann","year":"2022","journal-title":"Biorxiv"},{"key":"B55","doi-asserted-by":"publisher","DOI":"10.1016\/j.intimp.2021.107828","article-title":"Different T cell related immunological profiles in COVID-19 patients compared to healthy controls","volume":"97","author":"Khesht","year":"2021","journal-title":"Int Immunopharmacol"},{"key":"B56","doi-asserted-by":"publisher","DOI":"10.3390\/microorganisms9030546","article-title":"Recovery of innate immune cells and persisting alterations in adaptive immunity in the peripheral blood of convalescent plasma donors at eight months post SARS-CoV-2 infection","volume":"9","author":"Kostopoulos","year":"2021","journal-title":"Microorg"},{"key":"B57","doi-asserted-by":"publisher","DOI":"10.3390\/v13010026","article-title":"Peripheral blood immune profiling of convalescent plasma donors reveals alterations in specific immune subpopulations even at 2 months post SARS-CoV-2 infection","volume":"13","author":"Orologas-Stavrou","year":"2020","journal-title":"Viruses"},{"key":"B58","doi-asserted-by":"publisher","DOI":"10.1111\/all.14647","article-title":"Immunological imprint of COVID-19 on human peripheral blood leukocyte populations","volume":"76","author":"Kratzer","year":"2021","journal-title":"Allergy"},{"key":"B59","doi-asserted-by":"publisher","DOI":"10.1128\/mbio.00085-21","article-title":"Analysis of the long-term impact on cellular immunity in COVID-19-Recovered individuals reveals a profound NKT cell impairment","volume":"12","author":"Liu","year":"2021","journal-title":"Mbio"},{"key":"B60","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.741796","article-title":"Asymptomatic and mild SARS-CoV-2 infections elicit lower immune activation and higher specific neutralizing antibodies in children than in adults","volume":"12","author":"Petrara","year":"2021","journal-title":"Front Immunol"},{"key":"B61","doi-asserted-by":"publisher","DOI":"10.1002\/jlb.5cova0721-392rr","article-title":"Characterization of memory T cell subsets and common \u03b3\u2013chain cytokines in convalescent COVID-19 individuals","volume":"112","author":"Rajamanickam","year":"2022","journal-title":"J Leukocyte Biol"},{"key":"B62","doi-asserted-by":"publisher","first-page":"26","DOI":"10.1186\/s12916-021-02228-6","article-title":"Long-term perturbation of the peripheral immune system months after SARS-CoV-2 infection","volume":"20","author":"Ryan","year":"2022","journal-title":"BMC Med"},{"key":"B63","doi-asserted-by":"publisher","first-page":"720","DOI":"10.1016\/j.medj.2021.03.013","article-title":"Alterations in T and b cell function persist in convalescent COVID-19 patients","volume":"2","author":"Shuwa","year":"2021","journal-title":"Med"},{"key":"B64","doi-asserted-by":"publisher","DOI":"10.1111\/all.15372","article-title":"T-Cell recovery and evidence of persistent immune activation 12 months after severe COVID-19","volume":"77","author":"Taeschler","year":"2022","journal-title":"Allergy"},{"key":"B65","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2022.886431","article-title":"Remodeling of T cell dynamics during long COVID is dependent on severity of SARS-CoV-2 infection","volume":"13","author":"Wiech","year":"2022","journal-title":"Front Immunol"},{"key":"B66","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2022.848886","article-title":"Persistent overactive cytotoxic immune response in a Spanish cohort of individuals with long-COVID: Identification of diagnostic biomarkers","volume":"13","author":"Gal\u00e1n","year":"2022","journal-title":"Front Immunol"},{"key":"B67","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.700782","article-title":"Immune-based prediction of COVID-19 severity and chronicity decoded using machine learning","volume":"12","author":"Patterson","year":"2021","journal-title":"Front Immunol"},{"key":"B68","doi-asserted-by":"publisher","DOI":"10.3390\/biomedicines9111540","article-title":"A short corticosteroid course reduces symptoms and immunological alterations underlying long-COVID","volume":"9","author":"Utrero-Rico","year":"2021","journal-title":"Biomed"},{"key":"B69","doi-asserted-by":"publisher","DOI":"10.1152\/ajplung.00355.2020","article-title":"High-dimensional single-cell analysis reveals the immune characteristics of COVID-19","volume":"320","author":"Shi","year":"2021","journal-title":"Am J Physiol-lung C"},{"key":"B70","doi-asserted-by":"publisher","first-page":"1284","DOI":"10.1016\/j.immuni.2022.06.004","article-title":"Mass cytometry reveals a conserved immune trajectory of recovery in hospitalized COVID-19 patients","volume":"55","author":"Burnett","year":"2022","journal-title":"Immunity"},{"key":"B71","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.674279","article-title":"A virus-specific immune rheostat in the immunome of patients recovering from mild COVID-19","volume":"12","author":"Yeo","year":"2021","journal-title":"Front Immunol"},{"key":"B72","doi-asserted-by":"publisher","DOI":"10.1172\/jci137244","article-title":"Clinical and immunological features of severe and moderate coronavirus disease 2019","volume":"130","author":"Chen","year":"2020","journal-title":"J Clin Invest"},{"key":"B73","doi-asserted-by":"publisher","DOI":"10.1016\/j.jinf.2020.03.054","article-title":"Lymphocyte subset (CD4+, CD8+) counts reflect the severity of infection and predict the clinical outcomes in patients with COVID-19","volume":"81","author":"Liu","year":"2020","journal-title":"J Infection"},{"key":"B74","doi-asserted-by":"publisher","DOI":"10.1002\/cyto.a.24172","article-title":"Lymphocyte subset counts in COVID-19 patients: A meta-analysis","volume":"97","author":"Huang","year":"2020","journal-title":"Cytom Part A"},{"key":"B75","doi-asserted-by":"publisher","first-page":"3410","DOI":"10.1038\/s41467-020-17240-2","article-title":"Immunological and inflammatory profiles in mild and severe cases of COVID-19","volume":"11","author":"Song","year":"2020","journal-title":"Nat Commun"},{"key":"B76","doi-asserted-by":"publisher","DOI":"10.1172\/jci.insight.137799","article-title":"The laboratory tests and host immunity of COVID-19 patients with different severity of illness","volume":"5","author":"Wang","year":"2020","journal-title":"JCI Insight"},{"key":"B77","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciaa248","article-title":"Dysregulation of immune response in patients with coronavirus 2019 (COVID-19) in wuhan, China","volume":"71","author":"Qin","year":"2020","journal-title":"Clin Infect Dis Off Publ Infect Dis Soc Am"},{"key":"B78","doi-asserted-by":"publisher","DOI":"10.3390\/biomedicines9080917","article-title":"Innate and adaptive immune assessment at admission to predict clinical outcome in COVID-19 patients","volume":"9","author":"Segundo","year":"2021","journal-title":"Biomed"},{"key":"B79","doi-asserted-by":"publisher","DOI":"10.1111\/all.14866","article-title":"Profound dysregulation of T cell homeostasis and function in patients with severe COVID-19","volume":"76","author":"Adamo","year":"2021","journal-title":"Allergy"},{"key":"B80","doi-asserted-by":"publisher","first-page":"1607","DOI":"10.1016\/j.jaci.2015.10.035","article-title":"Physical exercise modulates the homeostasis of human regulatory T cells","volume":"137","author":"Weinhold","year":"2016","journal-title":"J Allergy Clin Immunol"},{"key":"B81","doi-asserted-by":"publisher","first-page":"1119","DOI":"10.1016\/j.immuni.2020.04.006","article-title":"Regulatory T cell-specific epigenomic region variants are a key determinant of susceptibility to common autoimmune diseases","volume":"52","author":"Ohkura","year":"2020","journal-title":"Immunity"},{"key":"B82","doi-asserted-by":"publisher","DOI":"10.1038\/s41422-020-0324-7","article-title":"Transcriptional and epigenetic basis of treg cell development and function: its genetic anomalies or variations in autoimmune diseases","volume":"30","author":"Ohkura","year":"2020","journal-title":"Cell Res"},{"key":"B83","doi-asserted-by":"publisher","DOI":"10.1016\/j.psyneuen.2021.105295","article-title":"Interleukin-6 as potential mediator of long-term neuropsychiatric symptoms of COVID-19","volume":"131","author":"Kappelmann","year":"2021","journal-title":"Psychoneuroendocrino"},{"key":"B84","doi-asserted-by":"publisher","DOI":"10.1038\/nature04753","article-title":"Reciprocal developmental pathways for the generation of pathogenic effector TH17 and regulatory T cells","volume":"441","author":"Bettelli","year":"2006","journal-title":"Nature"},{"key":"B85","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2020.596553","article-title":"Negative clinical evolution in COVID-19 patients is frequently accompanied with an increased proportion of undifferentiated Th cells and a strong underrepresentation of the Th1 subset","volume":"11","author":"Guti\u00e9rrez-Bautista","year":"2020","journal-title":"Front Immunol"},{"key":"B86","doi-asserted-by":"publisher","DOI":"10.1007\/s42000-022-00382-x","article-title":"Assessment of DHEAS, cortisol, and DHEAS\/cortisol ratio in patients with COVID-19: a pilot study","volume":"21","author":"Tomo","year":"2022","journal-title":"Hormones Athens Greece"},{"key":"B87","doi-asserted-by":"publisher","DOI":"10.1016\/j.cellsig.2021.110121","article-title":"A novel hypothesis for COVID-19 pathogenesis: Retinol depletion and retinoid signaling disorder","volume":"87","author":"Sarohan","year":"2021","journal-title":"Cell Signal"},{"key":"B88","doi-asserted-by":"publisher","DOI":"10.1002\/jmv.27222","article-title":"Post-COVID-19 complications: Multisystemic approach","volume":"93","author":"Suvvari","year":"2021","journal-title":"J Med Virol"},{"key":"B89","doi-asserted-by":"publisher","first-page":"e2289","DOI":"10.1002\/rmv.2289","article-title":"Long-term side effects and lingering symptoms post COVID-19 recovery","volume":"23","author":"Zarei","year":"2021","journal-title":"Rev Med Virol"},{"key":"B90","doi-asserted-by":"publisher","DOI":"10.1016\/j.amjmed.2021.07.004","article-title":"Post-COVID-19 tachycardia syndrome: A distinct phenotype of post-acute COVID-19 syndrome","volume":"134","author":"St\u00e5hlberg","year":"2021","journal-title":"Am J Med"},{"key":"B91","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijid.2020.09.016","article-title":"Covid-19 hyperinflammation and post-Covid-19 illness may be rooted in mast cell activation syndrome","volume":"100","author":"Afrin","year":"2020","journal-title":"Int J Infect Dis"},{"key":"B92","doi-asserted-by":"publisher","DOI":"10.1016\/j.hep.2003.09.026","article-title":"Suppression of HCV-specific T cells without differential hierarchy demonstrated ex vivo in persistent HCV infection","volume":"38","author":"Sugimoto","year":"2003","journal-title":"Hepatology"},{"key":"B93","doi-asserted-by":"publisher","DOI":"10.1038\/ni1181","article-title":"Natural regulatory T cells in infectious disease","volume":"6","author":"Belkaid","year":"2005","journal-title":"Nat Immunol"},{"key":"B94","doi-asserted-by":"publisher","DOI":"10.1182\/blood-2003-07-2598","article-title":"CD4+CD25+ regulatory T-cell deficiency in patients with hepatitis c-mixed cryoglobulinemia vasculitis","volume":"103","author":"Boyer","year":"2004","journal-title":"Blood"},{"key":"B95","doi-asserted-by":"publisher","DOI":"10.1093\/infdis\/jiac017","article-title":"Persistent autoimmune activation and proinflammatory state in post-coronavirus disease 2019 syndrome","volume":"225","author":"Acosta-Ampudia","year":"2022","journal-title":"J Infect Dis"},{"key":"B96","doi-asserted-by":"publisher","DOI":"10.1093\/cid\/ciab611","article-title":"Persistent symptoms in adult patients 1 year after coronavirus disease 2019 (COVID-19): A prospective cohort study","volume":"74","author":"See\u00dfle","year":"2021","journal-title":"Clin Infect Dis Off Publ Infect Dis Soc Am"},{"key":"B97","doi-asserted-by":"publisher","DOI":"10.1186\/s12967-022-03328-4","article-title":"Autoimmunity is a hallmark of post-COVID syndrome","volume":"20","author":"Rojas","year":"2022","journal-title":"J Transl Med"},{"key":"B98","doi-asserted-by":"publisher","DOI":"10.3389\/fmed.2021.754667","article-title":"Case report: Neutralization of autoantibodies targeting G-Protein-Coupled receptors improves capillary impairment and fatigue symptoms after COVID-19 infection","volume":"8","author":"Hohberger","year":"2021","journal-title":"Front Med"},{"key":"B99","doi-asserted-by":"publisher","DOI":"10.1038\/s41375-021-01175-8","article-title":"Severe clinical relapse in an immunocompromised host with persistent SARS-CoV-2 infection","volume":"35","author":"Reuken","year":"2021","journal-title":"Leukemia"},{"key":"B100","doi-asserted-by":"publisher","first-page":"NEJMc2031364","DOI":"10.1056\/nejmc2031364","article-title":"Persistence and evolution of SARS-CoV-2 in an immunocompromised host","volume":"383","author":"Choi","year":"2020","journal-title":"New Engl J Med"},{"key":"B101","doi-asserted-by":"publisher","DOI":"10.1097\/pg9.0000000000000152","article-title":"Persistent SARS-CoV-2 nucleocapsid protein presence in the intestinal epithelium of a pediatric patient 3 months after acute infection","volume":"3","author":"Arostegui","year":"2021","journal-title":"Jpgn Rep"},{"key":"B102","doi-asserted-by":"publisher","DOI":"10.1016\/s2213-2600(21)00240-x","article-title":"Persistence of SARS-CoV-2 RNA in lung tissue after mild COVID-19","volume":"9","author":"Ceulemans","year":"2021","journal-title":"Lancet Respir Med"},{"key":"B103","doi-asserted-by":"publisher","DOI":"10.1101\/2022.06.14.22276401","article-title":"Persistent circulating SARS-CoV-2 spike is associated with post-acute COVID-19 sequelae","volume":"2022","author":"Swank","year":"2022","journal-title":"Medrxiv"},{"key":"B104","doi-asserted-by":"publisher","first-page":"211","DOI":"10.1186\/s12879-022-07153-4","article-title":"Post-COVID-19 syndrome. SARS-CoV-2 RNA detection in plasma, stool, and urine in patients with persistent symptoms after COVID-19","volume":"22","author":"Tejerina","year":"2022","journal-title":"BMC Infect Dis"},{"key":"B105","doi-asserted-by":"publisher","DOI":"10.1177\/20499361211048572","article-title":"SARS-CoV-2 RNA in the cerebrospinal fluid of a patient with long COVID","volume":"8","author":"Viszlayov\u00e1","year":"2021","journal-title":"Ther Adv Infect Dis"},{"key":"B106","doi-asserted-by":"publisher","first-page":"3501","DOI":"10.1038\/s41467-021-23621-y","article-title":"Clinical and molecular characteristics of COVID-19 patients with persistent SARS-CoV-2 infection","volume":"12","author":"Yang","year":"2021","journal-title":"Nat Commun"},{"key":"B107","doi-asserted-by":"publisher","DOI":"10.1002\/cti2.1259","article-title":"Characteristics of T-cell responses in COVID-19 patients with prolonged SARS-CoV-2 positivity \u2013 a cohort study","volume":"10","author":"Yang","year":"2021","journal-title":"Clin Transl Immunol"},{"key":"B108","doi-asserted-by":"publisher","first-page":"70","DOI":"10.1038\/s41421-022-00441-y","article-title":"Enhanced inflammation and suppressed adaptive immunity in COVID-19 with prolonged RNA shedding","volume":"8","author":"Tang","year":"2022","journal-title":"Cell Discovery"},{"key":"B109","doi-asserted-by":"publisher","DOI":"10.1038\/s41586-018-0846-z","article-title":"Mitochondrial complex III is essential for suppressive function of regulatory T cells","volume":"565","author":"Weinberg","year":"2019","journal-title":"Nature"},{"key":"B110","doi-asserted-by":"publisher","DOI":"10.4049\/jimmunol.1600242","article-title":"Role of metabolism in the immunobiology of regulatory T cells","volume":"197","author":"Galgani","year":"2016","journal-title":"J Immunol"},{"key":"B111","doi-asserted-by":"publisher","DOI":"10.1002\/jlb.3ma0322-279rrr","article-title":"Loss of mitochondrial membrane potential (\u0394\u03a8 m) in leucocytes as post-COVID-19 sequelae","volume":"112","author":"D\u00edaz-Resendiz","year":"2022","journal-title":"J Leukocyte Biol"},{"key":"B112","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.202108-1903le","article-title":"Decreased fatty acid oxidation and altered lactate production during exercise in patients with post-acute COVID-19 syndrome","volume":"205","author":"de Boer","year":"2021","journal-title":"Am J Resp Crit Care"},{"key":"B113","doi-asserted-by":"publisher","DOI":"10.1016\/j.isci.2020.101631","article-title":"Mitochondria: In the cross fire of SARS-CoV-2 and immunity","volume":"23","author":"Burtscher","year":"2020","journal-title":"Iscience"},{"key":"B114","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.2024358118","article-title":"Redox imbalance links COVID-19 and myalgic encephalomyelitis\/chronic fatigue syndrome","volume":"118","author":"Paul","year":"2021","journal-title":"Proc Natl Acad Sci"},{"key":"B115","doi-asserted-by":"publisher","DOI":"10.1038\/nm1564","article-title":"Myelin-specific regulatory T cells accumulate in the CNS but fail to control autoimmune inflammation","volume":"13","author":"Korn","year":"2007","journal-title":"Nat Med"},{"key":"B116","doi-asserted-by":"publisher","DOI":"10.1038\/icb.2014.117","article-title":"Controlling the fire \u2014 tissue-specific mechanisms of effector regulatory T-cell homing","volume":"93","author":"Chow","year":"2015","journal-title":"Immunol Cell Biol"},{"key":"B117","doi-asserted-by":"publisher","DOI":"10.1164\/rccm.201202-0261oc","article-title":"BLT1-dependent alveolar recruitment of CD4+CD25+ Foxp3+ regulatory T cells is important for resolution of acute lung injury","volume":"186","author":"Wang","year":"2012","journal-title":"Am J Resp Crit Care"},{"key":"B118","doi-asserted-by":"publisher","DOI":"10.1016\/j.cell.2013.10.054","article-title":"A special population of regulatory T cells potentiates muscle repair","volume":"155","author":"Burzyn","year":"2013","journal-title":"Cell"},{"key":"B119","doi-asserted-by":"publisher","DOI":"10.1093\/eurheartj\/ehac031","article-title":"Long COVID: post-acute sequelae of COVID-19 with a cardiovascular focus","volume":"43","author":"Raman","year":"2022","journal-title":"Eur Heart J"},{"key":"B120","doi-asserted-by":"publisher","DOI":"10.1001\/jamacardio.2020.3557","article-title":"Outcomes of cardiovascular magnetic resonance imaging in patients recently recovered from coronavirus disease 2019 (COVID-19)","volume":"5","author":"Puntmann","year":"2020","journal-title":"JAMA Cardiol"},{"key":"B121","doi-asserted-by":"publisher","first-page":"11548","DOI":"10.1038\/s41598-020-68509-x","article-title":"CT features of COVID-19 patients with two consecutive negative RT-PCR tests after treatment","volume":"10","author":"Fu","year":"2020","journal-title":"Sci Rep-uk"},{"key":"B122","doi-asserted-by":"publisher","DOI":"10.1101\/2020.07.12.20151316","article-title":"Pericarditis and myocarditis long after SARS-CoV-2 infection: a cross-sectional descriptive study in health-care workers","volume":"2020","author":"Eiros","year":"2020","journal-title":"Medrxiv"},{"key":"B123","doi-asserted-by":"publisher","DOI":"10.3389\/fimmu.2021.763098","article-title":"Vascular damage, thromboinflammation, plasmablast activation, T-cell dysregulation and pathological histiocytic response in pulmonary draining lymph nodes of COVID-19","volume":"12","author":"Haslbauer","year":"2021","journal-title":"Front Immunol"},{"key":"B124","doi-asserted-by":"publisher","DOI":"10.1111\/imm.13603","article-title":"Dysfunctional phenotype of systemic and pulmonary regulatory T cells associates with lethal COVID-19 cases","author":"Gon\u00e7alves-Pereira","year":"2022","journal-title":"Immunology"},{"key":"B125","doi-asserted-by":"publisher","first-page":"81","DOI":"10.1016\/j.jaci.2020.09.009","article-title":"Compartmental immunophenotyping in COVID-19 ARDS: A case series","volume":"147","author":"Ronit","year":"2021","journal-title":"J Allergy Clin Immunol"},{"key":"B126","doi-asserted-by":"publisher","DOI":"10.1002\/cyto.a.23853","article-title":"OMIP-060: 30-parameter flow cytometry panel to assess T cell effector functions and regulatory T cells","volume":"95","author":"Liechti","year":"2019","journal-title":"Cytom Part A"},{"key":"B127","doi-asserted-by":"publisher","DOI":"10.1007\/s00262-015-1729-x","article-title":"Monitoring regulatory T cells in clinical samples: consensus on an essential marker set and gating strategy for regulatory T cell analysis by flow cytometry","volume":"64","author":"Santegoets","year":"2015","journal-title":"Cancer Immunol Immunother"},{"key":"B128","doi-asserted-by":"publisher","DOI":"10.1126\/scitranslmed.abn4338","article-title":"Elevated risk of infection with SARS-CoV-2 beta, gamma, and delta variant compared to alpha variant in vaccinated individuals","author":"Andeweg","year":"2022","journal-title":"Sci Transl Med"},{"key":"B129","doi-asserted-by":"publisher","DOI":"10.1126\/science.abn8652","article-title":"Structural basis of SARS-CoV-2 omicron immune evasion and receptor engagement","volume":"375","author":"McCallum","year":"2022","journal-title":"Science"},{"key":"B130","doi-asserted-by":"publisher","DOI":"10.1038\/s41586-021-04386-2","article-title":"Broadly neutralizing antibodies overcome SARS-CoV-2 omicron antigenic shift","volume":"602","author":"Cameroni","year":"2022","journal-title":"Nature"},{"key":"B131","doi-asserted-by":"publisher","DOI":"10.1126\/science.abm0811","article-title":"Heterologous infection and vaccination shapes immunity against SARS-CoV-2 variants","volume":"375","author":"Reynolds","year":"2022","journal-title":"Science"}],"container-title":["Frontiers in Immunology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fimmu.2022.1070994\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2022,12,13]],"date-time":"2022-12-13T01:48:11Z","timestamp":1670896091000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fimmu.2022.1070994\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2022,12,13]]},"references-count":131,"alternative-id":["10.3389\/fimmu.2022.1070994"],"URL":"https:\/\/doi.org\/10.3389\/fimmu.2022.1070994","relation":{"has-preprint":[{"id-type":"doi","id":"10.1101\/2022.10.04.22280642","asserted-by":"object"}]},"ISSN":["1664-3224"],"issn-type":[{"value":"1664-3224","type":"electronic"}],"subject":[],"published":{"date-parts":[[2022,12,13]]},"article-number":"1070994"}}