{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,3]],"date-time":"2026-07-03T18:07:25Z","timestamp":1783102045170,"version":"3.54.6"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,12]],"date-time":"2025-09-12T00:00:00Z","timestamp":1757635200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan","award":["AP14870256"],"award-info":[{"award-number":["AP14870256"]}]},{"name":"Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan","award":["AP23487566"],"award-info":[{"award-number":["AP23487566"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Rabies remains a fatal zoonotic disease, necessitating effective and affordable vaccines. While current vaccines are effective, they require multiple doses and may not induce long-lasting immunity in all settings. The rabies virus glycoprotein (RABV-G) is the principal antigen responsible for eliciting virus-neutralizing antibodies, but its recombinant monomeric forms often suffer from poor immunogenicity due to misfolding and aggregation. Methods: A recombinant trimeric RABV-G ectodomain (rRABV-G-XVIII) was engineered by fusing it to a human collagen XVIII-derived trimerization domain. The protein was expressed in E. coli, purified under denaturing conditions, and refolded. Trimer formation was verified using size-exclusion chromatography. Mice were immunized with rRABV-G-XVIII, with or without adjuvant, and compared to a monomeric form (rRABV-GE). Antigen-specific antibody responses were measured by ELISA, neutralizing activity was assessed, and protective efficacy was evaluated via intracerebral challenge with the CVS-27 rabies strain. Results: rRABV-G-XVIII formed stable trimers and induced strong humoral immune responses, with high ELISA titers and virus-neutralizing activity comparable to an inactivated rabies vaccine. Mice immunized with rRABV-GE showed lower antibody responses and partial protection, which improved with adjuvant. All rRABV-G-XVIII-immunized mice were fully protected against rabies challenge, independent of adjuvant use. Conclusions: Stabilization of RABV-G in its native trimeric conformation markedly improves immunogenicity and protective efficacy. This approach offers a promising strategy for the development of rabies subunit vac-cines with simplified formulations and potential for cost-effective production in bacterial systems.<\/jats:p>","DOI":"10.3390\/vaccines13090971","type":"journal-article","created":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T08:56:46Z","timestamp":1758013006000},"page":"971","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Immunogenicity and Antigenicity of the Recombinant Ectodomain of Rabies Virus Glycoprotein Containing the Human Collagen XVIII Trimerization Domain"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7739-7777","authenticated-orcid":false,"given":"Izat","family":"Smekenov","sequence":"first","affiliation":[{"name":"Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"},{"name":"Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gulshat","family":"Bayandy","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"},{"name":"Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7909-1835","authenticated-orcid":false,"given":"Sanzhar","family":"Alybayev","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"},{"name":"Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2827-644X","authenticated-orcid":false,"given":"Nuraiym","family":"Baltakhozha","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"},{"name":"Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhanat","family":"Batanova","sequence":"additional","affiliation":[{"name":"LLP Research and Production Enterprise \u201cAntigen\u201d, Almaty 040905, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nurlan","family":"Akhmetsadykov","sequence":"additional","affiliation":[{"name":"LLP Research and Production Enterprise \u201cAntigen\u201d, Almaty 040905, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7837-8685","authenticated-orcid":false,"given":"Amangeldy","family":"Bissenbaev","sequence":"additional","affiliation":[{"name":"Department of Molecular Biology and Genetics, Faculty of Biology and Biotechnology, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"},{"name":"Scientific Research Institute of Biology and Biotechnology Problems, Al-Farabi Kazakh National University, Almaty 050040, Kazakhstan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"001689","DOI":"10.1099\/jgv.0.001689","article-title":"ICTV virus taxonomy profile: Rhabdoviridae 2022","volume":"103","author":"Walker","year":"2022","journal-title":"J. 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