{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:21:54Z","timestamp":1760239314790,"version":"build-2065373602"},"reference-count":49,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2020,10,19]],"date-time":"2020-10-19T00:00:00Z","timestamp":1603065600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Health and Welfare","award":["HI15C2928"],"award-info":[{"award-number":["HI15C2928"]}]},{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2018R1A2B6003535","2018R1A6A1A03025124"],"award-info":[{"award-number":["2018R1A2B6003535","2018R1A6A1A03025124"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pharmaceutics"],"abstract":"<jats:p>Successful vaccines against specific pathogens often require multiple immunizations and adjuvant usage. Yet, assessing the protective efficacy of different immunization regimens with adjuvanted Toxoplasma gondii vaccines remains elusive. In this study, we investigated the vaccine efficacy induced by CpG-ODN-adjuvanted T. gondii virus-like particles (VLPs) after challenge infection with T. gondii (ME49) in mice (BALB\/c) upon one, two, and three immunizations. Immunization with adjuvanted T. gondii VLPs induced higher levels of T. gondii-specific IgG and\/or IgA antibody responses, germinal center (GC) B cells, total B cells, and CD4+ and CD8+ T cells compared with unadjuvanted VLPs. Increasing the number of immunizations was strongly correlated with enhanced protective immunity against T. gondii in mice, with the highest protection being demonstrated in mice thrice-immunized with either adjuvanted T. gondii VLPs or VLPs alone. Notably, lesser bodyweight reductions and cerebral cyst counts were observed in mice receiving multiple immunizations with the adjuvanted VLPs, thereby confirming the effectiveness of adjuvanted boost immunizations. These results demonstrated that multiple immunizations with T. gondii VLPs is an effective approach, and the CpG-ODN can be developed as an effective adjuvant for T. gondii VLP vaccines.<\/jats:p>","DOI":"10.3390\/pharmaceutics12100989","type":"journal-article","created":{"date-parts":[[2020,10,19]],"date-time":"2020-10-19T09:36:28Z","timestamp":1603100188000},"page":"989","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Evaluation of CpG-ODN-Adjuvanted Toxoplasma gondii Virus-Like Particle Vaccine upon One, Two, and Three Immunizations"],"prefix":"10.3390","volume":"12","author":[{"given":"Hae-Ji","family":"Kang","sequence":"first","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ki-Back","family":"Chu","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min-Ju","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul 02447, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyunwoo","family":"Park","sequence":"additional","affiliation":[{"name":"Health Park Co., Ltd., Seoul 06627, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hui","family":"Jin","sequence":"additional","affiliation":[{"name":"Health Park Co., Ltd., Seoul 06627, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Su-Hwa","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eun-Kyung","family":"Moon","sequence":"additional","affiliation":[{"name":"Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, 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":"Department of Medical Zoology, Kyung Hee University School of Medicine, Seoul 02447, Korea"},{"name":"Department of Medical Research Center for Bioreaction to Reactive Oxygen Species and Biomedical Science Institute, School of Medicine, Graduate School, Kyung Hee University, Seoul 02447, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2020,10,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"607","DOI":"10.1128\/MMBR.64.3.607-623.2000","article-title":"Lytic Cycle of Toxoplasma gondii","volume":"64","author":"Black","year":"2000","journal-title":"Microbiol. 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