{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,19]],"date-time":"2026-05-19T04:18:19Z","timestamp":1779164299187,"version":"3.51.4"},"reference-count":41,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T00:00:00Z","timestamp":1768003200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"crossref","award":["NRF2018R1A6A1A03025124"],"award-info":[{"award-number":["NRF2018R1A6A1A03025124"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"crossref","award":["RS-2025-25442355"],"award-info":[{"award-number":["RS-2025-25442355"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100002597","name":"Kyung Hee University","doi-asserted-by":"crossref","award":["KHU-20242268"],"award-info":[{"award-number":["KHU-20242268"]}],"id":[{"id":"10.13039\/501100002597","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Background\/Objectives: Toxoplasma gondii (T. gondii) dense granule antigen 14 (GRA14) is a parasitophorous vacuole membrane protein that plays a critical role in the development of chronic-stage cysts. However, its potential as a vaccine antigen and long-term immunity have not been evaluated using a virus-like particle (VLP) platform. Methods: influenza matrix protein (M1)-based VLPs displaying GRA14 were generated. Female BALB\/c mice were intranasally immunized with the VLP vaccine and orally challenged with lethal ME49 cysts either 10 weeks or 32 weeks after prime vaccination for short-term and long-term immunity evaluation, respectively. Results: GRA14 VLP vaccination elicited higher levels of T. gondii-specific IgG, IgG1, and IgG2a antibody responses in sera compared to non-immunized controls. Upon challenge infection, elevated IgG- and IgA-secreting plasma cells, germinal center B cells, and memory B cells were observed, and CD4+, CD8+ T-cells, as well as both Th1 (IFN-\u03b3) and Th2 (IL-4, IL-5) cytokines, were also increased. For the short-term immunity study, vaccinated mice exhibited suppressed cerebral inflammation, significantly reduced brain cyst burdens, maintained stable body weight, and achieved 100% survival. For the long-term study, GRA14 VLPs sustained elevated IgG and IgG1 levels as well as conferred partial yet significant protection, with lower cyst loads and 83% survival. Conclusions: GRA14 VLPs induce durable, balanced humoral and cellular immunity and provide both short-term and long-term protection against lethal chronic toxoplasmosis, supporting their potential as promising vaccine candidates.<\/jats:p>","DOI":"10.3390\/pharmaceutics18010093","type":"journal-article","created":{"date-parts":[[2026,1,12]],"date-time":"2026-01-12T10:25:23Z","timestamp":1768213523000},"page":"93","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Protection Against Toxoplasma gondii Lethal ME49 Challenge Induced by Influenza Virus-like Particles Containing Dense Granule Protein 14"],"prefix":"10.3390","volume":"18","author":[{"given":"Jie","family":"Mao","sequence":"first","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hae-Ji","family":"Kang","sequence":"additional","affiliation":[{"name":"Department of Microbiology, Dongguk University College of Medicine, Gyeongju 38066, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gi-Deok","family":"Eom","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Su In","family":"Heo","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hynnu","family":"Nam","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ji-Hyun","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Department of Biology, Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ki-Ho","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Infectious Diseases, Kyung Hee University Hospital, Kyung Hee University School of Medicine, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mi Suk","family":"Lee","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Department of Internal Medicine, Kyung Hee University College of Medicine, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6817-7668","authenticated-orcid":false,"given":"Sung Soo","family":"Kim","sequence":"additional","affiliation":[{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0419-9339","authenticated-orcid":false,"given":"Fu-Shi","family":"Quan","sequence":"additional","affiliation":[{"name":"Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, Core Research Institute (CRI), Kyung Hee University, Seoul 02447, Republic of Korea"},{"name":"Department of Medical Zoology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,10]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"944","DOI":"10.1016\/j.pt.2019.07.001","article-title":"Toxoplasma gondii","volume":"35","author":"Lourido","year":"2019","journal-title":"Trends Parasitol."},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Daher, D., Shaghlil, A., Sobh, E., Hamie, M., Hassan, M.E., Moumneh, M.B., Itani, S., El Hajj, R., Tawk, L., and El Sabban, M. 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