{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,13]],"date-time":"2026-10-13T12:35:38Z","timestamp":1791894938247,"version":"4.3.4"},"reference-count":45,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2025,9,24]],"date-time":"2025-09-24T00:00:00Z","timestamp":1758672000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o de Apoio \u00e0 Pesquisa e Extens\u00e3o","award":["310058\/2022-8"],"award-info":[{"award-number":["310058\/2022-8"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Toxoplasmosis is a relevant parasitic infection in sheep, with ovine meat an important source of human exposure. Accurate detection of the early immune response to Toxoplasma gondii is essential for preventing reproductive losses and improving diagnostic strategies. This study evaluated the kinetics of the acute immune response in eighteen sheep experimentally exposed to live tachyzoites or immunized with parasite-derived glycoconjugates (GlyC). Animals were divided into three groups and injected with saline solution, tachyzoites, or glycoconjugates combined with an adjuvant. Infected sheep developed specific IgM antibodies against both lysate and glycoconjugate antigens from day 4, and IgG against glycoconjugates from day 12 post-infection. Glycoconjugate-immunized sheep produced IgM against lysate antigens from day 4, and IgG against both antigens from day 12. Flow cytometry revealed a significant increase in circulating CD8+ T cells and a reduction in MHC class II+ cells on day 60 in the infected group. These findings demonstrate the early humoral and cellular immune response profiles following infection or GlyC immunization. This supports their future application in diagnostic tests or as vaccine candidates against toxoplasmosis in sheep.<\/jats:p>","DOI":"10.3390\/vetsci12100928","type":"journal-article","created":{"date-parts":[[2025,9,24]],"date-time":"2025-09-24T10:39:42Z","timestamp":1758710382000},"page":"928","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["The Acute Immune Response in Sheep Following Immunization with Toxoplasma gondii Tachyzoites or Parasite-Derived Glycoconjugates"],"prefix":"10.3390","volume":"12","author":[{"given":"Patr\u00edcia Oliveira","family":"Meira-Santos","sequence":"first","affiliation":[{"name":"Veterinary Medicine Department, Universidade Federal de Sergipe, S\u00e3o Crist\u00f3v\u00e3o 49107-230, SE, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela Cruz","family":"Piedade","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria Tereza","family":"Guedes","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dan","family":"Loureiro","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2771-0235","authenticated-orcid":false,"given":"Jos\u00e9 Tadeu","family":"Raynal","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roberto","family":"Meyer","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5138-9894","authenticated-orcid":false,"given":"Let\u00edcia","family":"Vicentini","sequence":"additional","affiliation":[{"name":"Tropical Medicine Unit, Health Sciences Center, Universidade Federal do Esp\u00edrito Santo, Vit\u00f3ria 29047-105, ES, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9021-2397","authenticated-orcid":false,"given":"Luiz","family":"Soares","sequence":"additional","affiliation":[{"name":"Tropical Medicine Unit, Health Sciences Center, Universidade Federal do Esp\u00edrito Santo, Vit\u00f3ria 29047-105, ES, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Blima","family":"Fux","sequence":"additional","affiliation":[{"name":"Tropical Medicine Unit, Health Sciences Center, Universidade Federal do Esp\u00edrito Santo, Vit\u00f3ria 29047-105, ES, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9095-776X","authenticated-orcid":false,"given":"Ricardo Wagner","family":"Portela","sequence":"additional","affiliation":[{"name":"Laboratory of Immunology and Molecular Biology, Health Sciences Institute, Universidade Federal da Bahia, Salvador 40110-100, BA, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"106432","DOI":"10.1016\/j.actatropica.2022.106432","article-title":"Toxoplasmosis in Human and Animals Around the World: Diagnosis and Perspectives in the One Health Approach","volume":"231","author":"Torrecilhas","year":"2022","journal-title":"Acta Trop."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"041","DOI":"10.4025\/revcivet.v6i1.41361","article-title":"Meta-an\u00e1lise da preval\u00eancia de toxoplasmose em gatos e ovinos no Brasil","volume":"6","author":"Lugoch","year":"2018","journal-title":"Rev. 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