{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:09:26Z","timestamp":1792789766148,"version":"4.5.0"},"reference-count":56,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T00:00:00Z","timestamp":1762387200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Brazilian Federal Government"},{"name":"Ministry of Health"}],"content-domain":{"domain":["www.mdpi.com"],"crossmark-restriction":true},"short-container-title":["Pathogens"],"abstract":"<jats:p>Neutralizing antibodies (nAbs) are key indicators of protection against SARS-CoV-2, and their measurement remains essential for monitoring vaccine responses and population immunity. While the plaque reduction neutralization test (PRNT) is the gold standard, it relies on replicative viruses and is not suited for high-throughput applications. Here, both an in-house and a commercial pseudovirus-based neutralization (PBN) assay were standardized and compared with PRNT to assess performance and concordance. The in-house PBN employed a VSV-\u0394G pseudovirus encoding NanoLuc and displaying the SARS-CoV-2 Spike from the Wuhan or Omicron BA.1 variants in HEK293T-hACE2 cells, whereas the commercial assay (Integral Molecular, Philadelphia, PA, USA) used a lentiviral backbone with Renilla or GFP reporters and Wuhan or Omicron XBB.1.5\/XBB.1.9 Spikes in Vero E6-ACE2-TMPRSS2 cells. Both assays showed strong correlations with PRNT, the commercial assay; moreover, they offered superior reproducibility and scalability, while the in-house version provided a cost-effective alternative suitable for BSL-2 settings. A total of 600 serum samples from vaccinated individuals were analyzed by commercial PBN at collection time points, from pre-vaccination to twelve months post\u2013second dose, enabling large-scale screening, revealing marked differences in neutralization between Wuhan and Omicron XBB.1.5\/1.9, and allowing unbiased classification of low, medium, and high responders using k-means clustering. The geometric mean titers (log10 GMT) highlighted a ~1.5 log10 (eightfold) reduction in neutralizing activity against Omicron, reflecting antibody waning and antigenic drift. Altogether, this study integrates assay standardization, PRNT comparison, and large-scale immune profiling, establishing a robust framework for harmonized pseudovirus-based neutralization testing.<\/jats:p>","DOI":"10.3390\/pathogens14111129","type":"journal-article","created":{"date-parts":[[2025,11,6]],"date-time":"2025-11-06T10:08:51Z","timestamp":1762423731000},"page":"1129","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Pseudovirus-Based Neutralization Assays as Customizable and Scalable Tools for Serological Surveillance and Immune Profiling"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0625-5827","authenticated-orcid":false,"given":"Caio Bidueira","family":"Denani","sequence":"first","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"},{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Medicina Tropical, Instituto Oswaldo Cruz (IOC), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bruno Pimenta","family":"Setatino","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Denise","family":"Pereira","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0889-6991","authenticated-orcid":false,"given":"Ingrid Siciliano","family":"Horbach","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7401-5107","authenticated-orcid":false,"given":"Adriana Souza","family":"Azevedo","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gabriela","family":"Coutinho","sequence":"additional","affiliation":[{"name":"Departamento de Desenvolvimento Experimental e Pr\u00e9-Cl\u00ednico (DEDEP), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clara Lucy","family":"Ferroco","sequence":"additional","affiliation":[{"name":"Departamento de Assuntos M\u00e9dicos, Estudos Cl\u00ednicos e Vigil\u00e2ncia P\u00f3s-Registro (DEAME), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7686-6490","authenticated-orcid":false,"given":"Jana\u00edna","family":"Xavier","sequence":"additional","affiliation":[{"name":"Departamento de Assuntos M\u00e9dicos, Estudos Cl\u00ednicos e Vigil\u00e2ncia P\u00f3s-Registro (DEAME), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-8099-1899","authenticated-orcid":false,"given":"Robson","family":"Leite","sequence":"additional","affiliation":[{"name":"Departamento de Assuntos M\u00e9dicos, Estudos Cl\u00ednicos e Vigil\u00e2ncia P\u00f3s-Registro (DEAME), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ewerton","family":"Santos","sequence":"additional","affiliation":[{"name":"Departamento de Assuntos M\u00e9dicos, Estudos Cl\u00ednicos e Vigil\u00e2ncia P\u00f3s-Registro (DEAME), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria de Lourdes","family":"Maia","sequence":"additional","affiliation":[{"name":"Departamento de Assuntos M\u00e9dicos, Estudos Cl\u00ednicos e Vigil\u00e2ncia P\u00f3s-Registro (DEAME), Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8095-8846","authenticated-orcid":false,"given":"Waleska Dias","family":"Schwarcz","sequence":"additional","affiliation":[{"name":"Laborat\u00f3rio de An\u00e1lise Imunomolecular, Instituto de Tecnologia em Imunobiol\u00f3gicos (Bio-Manguinhos), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1840-3302","authenticated-orcid":false,"given":"Ivanildo Pedro","family":"Sousa","sequence":"additional","affiliation":[{"name":"Programa de P\u00f3s-Gradua\u00e7\u00e3o em Medicina Tropical, Instituto Oswaldo Cruz (IOC), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"},{"name":"Laborat\u00f3rio de Virologia e Parasitologia Molecular, Instituto Oswaldo Cruz (IOC), Funda\u00e7\u00e3o Oswaldo Cruz, Rio de Janeiro 21040-360, Brazil"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,11,6]]},"reference":[{"key":"ref_1","unstructured":"(2025, August 07). 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