{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T12:12:55Z","timestamp":1785413575902,"version":"3.56.0"},"reference-count":44,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T00:00:00Z","timestamp":1782345600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundamental Research Program of Shanxi Province","award":["202403021212085"],"award-info":[{"award-number":["202403021212085"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["32402912"],"award-info":[{"award-number":["32402912"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"award":["32402912"],"award-info":[{"award-number":["32402912"]}],"id":[{"id":"https:\/\/ror.org\/01h0zpd94","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Science and Technology Innovation Program of Shanxi Agricultural University","award":["2023BQ62"],"award-info":[{"award-number":["2023BQ62"]}]},{"award":["2023BQ62"],"award-info":[{"award-number":["2023BQ62"]}],"id":[{"id":"https:\/\/ror.org\/05e9f5362","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Shanxi Province Excellent Doctoral Work Award-Scientific Research Project","award":["SXBYKY2024025"],"award-info":[{"award-number":["SXBYKY2024025"]}]},{"name":"Special Research Fund of Shanxi Agricultural University for High-level Talents","award":["2021XG001"],"award-info":[{"award-number":["2021XG001"]}]},{"award":["2021XG001"],"award-info":[{"award-number":["2021XG001"]}],"id":[{"id":"https:\/\/ror.org\/05e9f5362","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control","award":["202504010931010"],"award-info":[{"award-number":["202504010931010"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>Toxoplasma gondii is an apicomplexan parasite that causes toxoplasmosis, a widespread zoonotic disease leading to serious public health concerns and economic losses to animal husbandry. Currently, highly effective vaccines against toxoplasmosis remain unavailable. This study aimed to investigate the safety, immunogenicity, and protective efficacy of the gra47-deficient mutant strain Pru\u0394gra47 as a live-attenuated vaccine candidate. We evaluated the virulence of Pru\u0394gra47 in a mouse model, determined the optimal immunization dose, and measured serum antibody levels and cytokine profiles. Then, mice immunized with Pru\u0394gra47 were challenged with different T. gondii strains to assess protection against acute and chronic infection. Pru\u0394gra47 displayed significantly attenuated virulence and its ability to form cysts was weakened. Vaccination with 5 \u00d7 106 tachyzoites elicited predominantly Th1-skewed immune responses. Immunization with Pru\u0394gra47 provided complete protection against challenge infection with relatively low-virulent PYS strain and homologous Pru strain, prolonged survival against the highly virulent RH strain, and achieved a 90% survival rate with reduced brain cyst burden under chronic challenge. In conclusion, Pru\u0394gra47 is relatively safe and immunogenic in the murine model, and is worth being evaluated in food-producing animals and cats.<\/jats:p>","DOI":"10.3390\/ani16131964","type":"journal-article","created":{"date-parts":[[2026,6,25]],"date-time":"2026-06-25T12:37:55Z","timestamp":1782391075000},"page":"1964","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["The Live-Attenuated Pru\u0394gra47 Strain of Toxoplasma gondii Confers Protective Immunity Against Acute and Chronic Toxoplasmosis in Mice"],"prefix":"10.3390","volume":"16","author":[{"given":"Chen-Ran","family":"Tian","sequence":"first","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-4013-8520","authenticated-orcid":false,"given":"Xing","family":"Tian","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shu-Min","family":"Zhao","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhi","family":"Zheng","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wen-Bo","family":"Hao","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2530-4628","authenticated-orcid":false,"given":"Xing-Quan","family":"Zhu","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-6224-3603","authenticated-orcid":false,"given":"Xiao-Nan","family":"Zheng","sequence":"additional","affiliation":[{"name":"Shanxi Key Laboratory of Animal Disease Research, Prevention and Control, College of Veterinary Medicine, Shanxi Agricultural University, Jinzhong 030801, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,25]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e00115-19","DOI":"10.1128\/CMR.00115-19","article-title":"Epidemiology, pathophysiology, diagnosis, and management of cerebral toxoplasmosis","volume":"34","author":"Elsheikha","year":"2021","journal-title":"Clin. 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