{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,27]],"date-time":"2026-02-27T17:19:28Z","timestamp":1772212768412,"version":"3.50.1"},"reference-count":28,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T00:00:00Z","timestamp":1639094400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Provosts Academic Priorities Fund, The Aga Khan University"},{"DOI":"10.13039\/501100007601","name":"Horizon 2020","doi-asserted-by":"publisher","award":["667824 \u2013 EXCELLtoINNOV"],"award-info":[{"award-number":["667824 \u2013 EXCELLtoINNOV"]}],"id":[{"id":"10.13039\/501100007601","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Individuals recovering from COVID-19 are known to have antibodies against the Spike and other structural proteins. Antibodies against Spike have been shown to display viral neutralization. However, not all antibodies against Spike have neutralizing ability although they may be cross-reactive. There is a need for easy-to-use SARS-CoV-2 neutralizing assays for the determination of virus-neutralizing activity in sera of individuals. Here we describe a PCR-based micro\u2010neutralization assay that can be used to evaluate the viral neutralization titers of serum from SARS-CoV-2 infected individuals.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec002\">\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>The SARS-CoV-2 strain used was isolated from a nasopharyngeal specimen of a COVID-19 case. The limiting dilution method was used to obtain a 50% tissue culture infective dose (TCID50) of Vero cells. For the micro\u2010neutralization assay, 19 serum samples, with positive IgG titers against Spike Receptor-Binding Domain (RBD) were tested. After 24 hours, infected cells were inspected for the presence of a cytopathic effect, lysed and RNA RT-PCR conducted for SARS-CoV-2. PCR target Ct values were used to calculate percent neutralization\/inhibition of SARS-CoV-2.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec003\">\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Out of 19 samples, 13 samples gave 100% neutralization at all dilutions, 1 sample showed neutralization at the first dilution, 4 samples showed neutralization at lower dilutions, while one sample did not demonstrate any neutralization. The RBD ODs and neutralization potential percentages were found to be positively correlated.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec id=\"sec004\">\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>We describe a rapid RT-PCR-based SARS-CoV-2 microneutralization assay for the detection of neutralizing antibodies. This can effectively be used to test the antiviral activity of serum antibodies for the investigation of both disease-driven and vaccine-induced responses.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1371\/journal.pone.0259551","type":"journal-article","created":{"date-parts":[[2021,12,10]],"date-time":"2021-12-10T13:34:36Z","timestamp":1639143276000},"page":"e0259551","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":13,"title":["A rapid real-time polymerase chain reaction-based live virus microneutralization assay for detection of neutralizing antibodies against SARS-CoV-2 in blood\/serum"],"prefix":"10.1371","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9497-0902","authenticated-orcid":true,"given":"Syed Hani","family":"Abidi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kehkashan","family":"Imtiaz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Akbar","family":"Kanji","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shama","family":"Qaiser","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Erum","family":"Khan","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kiran","family":"Iqbal","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Marc","family":"Veldhoen","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kulsoom","family":"Ghias","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"J. 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