{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T06:28:49Z","timestamp":1775111329490,"version":"3.50.1"},"reference-count":30,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2019,7,8]],"date-time":"2019-07-08T00:00:00Z","timestamp":1562544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["31730029"],"award-info":[{"award-number":["31730029"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"The Major Infectious Disease Project","award":["2018ZX10101001-002"],"award-info":[{"award-number":["2018ZX10101001-002"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Background: To date, there is no licensed vaccine available to prevent respiratory syncytial virus (RSV) infection. The valuable pre-fusion conformation of the fusion protein (pre-F) is prone to lose high neutralizing antigenic sites. The goals of this study were to stabilize pre-F protein by fixatives and try to find the possibility of developing an inactivated RSV vaccine. Methods: The screen of the optimal fixative condition was performed with flow cytometry. BALB\/c mice were immunized intramuscularly with different immunogens. The serum neutralizing antibody titers of immunized mice were determined by neutralization assay. The protection and safety of these immunogens were assessed. Results: Fixation in an optimal concentration of formaldehyde (0.0244%\u20130.0977%) or paraformaldehyde (0.0625%\u20131%) was able to stabilize pre-F. Additionally, BALB\/c mice inoculated with optimally stabilized pre-F protein (opti-fixed) induced a higher anti-RSV neutralization (9.7 log2, mean value of dilution rate) than those inoculated with unstable (unfixed, 8.91 log2, p &lt; 0.01) or excessively fixed (exce-fixed, 7.28 log2, p &lt; 0.01) pre-F protein. Furthermore, the opti-fixed immunogen did not induce enhanced RSV disease. Conclusions: Only the proper concentration of fixatives could stabilize pre-F and the optimal formaldehyde condition provides a potential reference for development of an inactivated RSV vaccine.<\/jats:p>","DOI":"10.3390\/v11070628","type":"journal-article","created":{"date-parts":[[2019,7,8]],"date-time":"2019-07-08T11:02:37Z","timestamp":1562583757000},"page":"628","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["The Optimal Concentration of Formaldehyde is Key to Stabilizing the Pre-Fusion Conformation of Respiratory Syncytial Virus Fusion Protein"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7462-8763","authenticated-orcid":false,"given":"Wei","family":"Zhang","sequence":"first","affiliation":[{"name":"National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lu-Jing","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lu-Ting","family":"Zhan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min","family":"Zhao","sequence":"additional","affiliation":[{"name":"National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Guang-Hua","family":"Wu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun-Yu","family":"Si","sequence":"additional","affiliation":[{"name":"National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Li","family":"Chen","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xue","family":"Lin","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yong-Peng","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Min","family":"Lin","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chao","family":"Yu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mu-Jin","family":"Fang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ying-Bin","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0099-4212","authenticated-orcid":false,"given":"Zi-Zheng","family":"Zheng","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0179-5266","authenticated-orcid":false,"given":"Ning-Shao","family":"Xia","sequence":"additional","affiliation":[{"name":"National Institute of Diagnostics and Vaccine Development in Infectious Diseases, School of Life Sciences, Xiamen University, Xiamen, Fujian 361005, China"},{"name":"State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics, School of Public Health, Xiamen University, Xiamen, Fujian 361005, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,7,8]]},"reference":[{"key":"ref_1","first-page":"39","article-title":"Clinical and epidemiologic features of respiratory syncytial virus","volume":"372","author":"Hall","year":"2013","journal-title":"Curr. 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