{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,21]],"date-time":"2026-06-21T05:55:05Z","timestamp":1782021305689,"version":"3.54.5"},"reference-count":45,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2024,9,30]],"date-time":"2024-09-30T00:00:00Z","timestamp":1727654400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Fundamental Research Grant Scheme, Malaysia Ministry of Higher Education (MoHE)","award":["FRGS\/1\/2021\/STG03\/UKM\/02\/2"],"award-info":[{"award-number":["FRGS\/1\/2021\/STG03\/UKM\/02\/2"]}]},{"name":"Fundamental Research Grant Scheme, Malaysia Ministry of Higher Education (MoHE)","award":["NMRR ID-22-01257-WCO"],"award-info":[{"award-number":["NMRR ID-22-01257-WCO"]}]},{"name":"Ministry of Health, Malaysia (MOH)","award":["FRGS\/1\/2021\/STG03\/UKM\/02\/2"],"award-info":[{"award-number":["FRGS\/1\/2021\/STG03\/UKM\/02\/2"]}]},{"name":"Ministry of Health, Malaysia (MOH)","award":["NMRR ID-22-01257-WCO"],"award-info":[{"award-number":["NMRR ID-22-01257-WCO"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Comprehending the replication kinetics of SARS-CoV-2 variants helps explain why certain variants spread more easily, are more contagious, and pose a significant health menace to global populations. The replication kinetics of the Malaysian isolates of Alpha, Beta, Delta, and Omicron variants were studied in the Vero E6 cell line. Their replication kinetics were determined using the plaque assay, quantitative real-time PCR (qRT-PCR), and the viral growth curve. The Beta variant exhibited the highest replication rate at 24 h post-infection (h.p.i), as evidenced by the highest viral titers and lowest viral RNA multiplication threshold. The plaque phenotypes also varied among the variants, in which the Beta and Omicron variants formed the largest and smallest plaques, respectively. All studied variants showed strong cytopathic effects after 48 h.p.i. The whole-genome sequencing highlighted cell-culture adaptation, where the Beta, Delta, and Omicron variants acquired mutations at the multibasic cleavage site after three cycles of passaging. The findings suggest a strong link between the replication rates and their respective transmissibility and pathogenicity. This is essential in predicting the impacts of the upcoming variants on the local and global populations and is useful in designing preventive measures to curb virus outbreaks.<\/jats:p>","DOI":"10.3390\/ijms251910541","type":"journal-article","created":{"date-parts":[[2024,9,30]],"date-time":"2024-09-30T05:45:27Z","timestamp":1727675127000},"page":"10541","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Insights into the Replication Kinetics Profiles of Malaysian SARS-CoV-2 Variant Alpha, Beta, Delta, and Omicron in Vero E6 Cell Line"],"prefix":"10.3390","volume":"25","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5727-7359","authenticated-orcid":false,"given":"Zarina","family":"Mohd Zawawi","sequence":"first","affiliation":[{"name":"Virology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health, Shah Alam 40170, Malaysia"},{"name":"Center for Toxicology and Health Risk Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-1555-1507","authenticated-orcid":false,"given":"Jeevanathan","family":"Kalyanasundram","sequence":"additional","affiliation":[{"name":"Virology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rozainanee","family":"Mohd Zain","sequence":"additional","affiliation":[{"name":"Virology Unit, Infectious Disease Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5690-8008","authenticated-orcid":false,"given":"Adiratna","family":"Mat Ripen","sequence":"additional","affiliation":[{"name":"Cancer Research Centre, Institute for Medical Research, National Institutes of Health, Ministry of Health, Shah Alam 40170, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dayang Fredalina","family":"Basri","sequence":"additional","affiliation":[{"name":"Center for Diagnostic, Therapeutic and Investigative Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2449-8395","authenticated-orcid":false,"given":"Wei Boon","family":"Yap","sequence":"additional","affiliation":[{"name":"Center for Toxicology and Health Risk Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur 50300, Malaysia"},{"name":"One Health UKM, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,9,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"107365","DOI":"10.1016\/j.intimp.2021.107365","article-title":"An overview of Betacoronaviruses-associated severe respiratory syndromes, focusing on sex-type-specific immune responses","volume":"92","author":"Rahimi","year":"2021","journal-title":"Int. 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