{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,16]],"date-time":"2026-05-16T02:52:39Z","timestamp":1778899959118,"version":"3.51.4"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T00:00:00Z","timestamp":1672099200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["TropicalMed"],"abstract":"<jats:p>High IL-10 levels are pivotal to parasite survival in visceral leishmaniasis (VL). Antigenic stimuli induce IL-10 expression and release of adenosine by CD39\/CD73. Due their intrinsic ability to express IL-10 and produce adenosine from extracellular ATP, we evaluated the IL-10, CD39, and CD73 expression by Regulatory T cells (Treg) correlated with VL pathology. Using flow cytometry, Treg cells was analyzed in peripheral blood samples from VL patients (in the presence and absence of Leishmania infantum soluble antigen (SLA)) and healthy individuals (negative endemic control\u2014NEC group), without any treatment. Additionally, IL-10 levels in leukocytes culture supernatant were measured in all groups by ELISA assay. VL patients presented more Treg frequency than NEC group, independently of stimulation. ELISA results demonstrated that SLA induced higher IL-10 expression in the VL group. However, the NEC group had a higher Treg IL-10+ compared to the VL group without stimulation and SLA restored the IL-10 in Treg. Additionally, an increase in Treg CD73+ in the VL group independently of stimuli compared to that in the NEC group was observed. We suggest that Treg are not the main source of IL-10, while the CD73 pathway may be an attempt to modulate the exacerbation of immune response in VL disease.<\/jats:p>","DOI":"10.3390\/tropicalmed8010018","type":"journal-article","created":{"date-parts":[[2022,12,27]],"date-time":"2022-12-27T02:55:07Z","timestamp":1672109707000},"page":"18","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Characterization of Regulatory T Cells in Patients Infected by Leishmania Infantum"],"prefix":"10.3390","volume":"8","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1060-4740","authenticated-orcid":false,"given":"Rephany F.","family":"Peixoto","sequence":"first","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bruna M.","family":"Gois","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marineuma","family":"Martins","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9323-7677","authenticated-orcid":false,"given":"Pedro Henrique S.","family":"Palmeira","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Juliana C.","family":"Rocha","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8332-2907","authenticated-orcid":false,"given":"Juliana A. S.","family":"Gomes","sequence":"additional","affiliation":[{"name":"Department of Morphology, Institute of Biological Sciences, Federal University of Minas Gerais, Pampulha, Belo Horizonte 31270-901, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"F\u00e1tima L. A. A.","family":"Azevedo","sequence":"additional","affiliation":[{"name":"Research Institute for Drugs and Medicines, Federal University of Para\u00edba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2083-6898","authenticated-orcid":false,"given":"Robson C.","family":"Veras","sequence":"additional","affiliation":[{"name":"Research Institute for Drugs and Medicines, Federal University of Para\u00edba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isac A.","family":"de Medeiros","sequence":"additional","affiliation":[{"name":"Research Institute for Drugs and Medicines, Federal University of Para\u00edba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Teresa C. S. L.","family":"Grisi","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dem\u00e9trius A. M.","family":"de Ara\u00fajo","sequence":"additional","affiliation":[{"name":"Department of Biotechnology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1923-6219","authenticated-orcid":false,"given":"Ian P. G.","family":"Amaral","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0964-389X","authenticated-orcid":false,"given":"Tatjana S. L.","family":"Keesen","sequence":"additional","affiliation":[{"name":"Immunology of Infectious Diseases Laboratory, Department of Cellular and Molecular Biology, Federal University of Paraiba, Jo\u00e3o Pessoa 58051-900, Brazil"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,12,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"25","DOI":"10.2147\/DDDT.S146521","article-title":"Leishmaniasis in humans: Drug or vaccine therapy?","volume":"12","author":"Ghorbani","year":"2018","journal-title":"Drug. Des. Devel. Ther."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"833","DOI":"10.1007\/s00104-019-0994-1","article-title":"Viszerale Leishmaniose","volume":"90","author":"Wilhelm","year":"2019","journal-title":"Der. 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