{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T13:28:24Z","timestamp":1790947704967,"version":"4.1.0"},"reference-count":47,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2026,5,30]],"date-time":"2026-05-30T00:00:00Z","timestamp":1780099200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"ILiAD Biotechnologies"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background\/Objectives: Pertussis, caused by Bordetella pertussis, remains a global health problem, despite high vaccine coverage. In countries with high acellular pertussis vaccine (aPV) coverage, pertactin-negative B. pertussis strains emerged due to vaccine pressure on the sole bactericidal target of aPVs. In contrast, the live attenuated intranasal vaccine BPZE1 induces bactericidal antibodies to multiple antigenic targets that kill pertactin-positive and pertactin-negative B. pertussis strains. Here, we developed two high-throughput human complement-mediated serum bactericidal assays (SBA) using clinical samples to demonstrate bactericidal activity against B. pertussis. Methods: Assay accuracy, precision, linearity, range and robustness of the SBAs against pertactin-positive and pertactin-negative B. pertussis strain B1917 were determined using a panel of commercial and clinical trial samples. The assay was used to analyze a cohort of BPZE1 and tetanus\u2013diphtheria\u2013acellular pertussis (Tdap) vaccinee samples at baseline and 28 days post-vaccination from a phase 2b clinical trial. Results: Inter- and intra-assay variability of both assays had coefficients of variation for repeatability &lt; 20% and for intermediate precision of &lt;30%. The assays measured titers ranging from ~8 to ~20,000 and showed high linearity (R2 &gt; 0.98) between bactericidal titers and serum dilutions. On clinical samples, BPZE1 induced similar bactericidal activity as Tdap against pertactin-positive B. pertussis, despite inducing lower anti-aP antigen IgG concentrations than Tdap. Additionally, BPZE1 induced serum bactericidal activity against pertactin-negative B. pertussis, while Tdap did not. Conclusions: High-throughput SBAs were developed and qualified against pertactin-positive and pertactin-negative B. pertussis, enabling measurement of 120 samples per day per analyst. These assays will support clinical development of next-generation pertussis vaccines, including BPZE1.<\/jats:p>","DOI":"10.3390\/vaccines14060492","type":"journal-article","created":{"date-parts":[[2026,6,2]],"date-time":"2026-06-02T12:45:08Z","timestamp":1780404308000},"page":"492","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Development of High-Throughput Serum Bactericidal Assays for Bordetella pertussis to Evaluate BPZE1"],"prefix":"10.3390","volume":"14","author":[{"given":"Peter","family":"Goldstein","sequence":"first","affiliation":[{"name":"ILiAD Biotechnologies, Inc., Weston, FL 33331, USA"},{"name":"Department of Biomedical Engineering, University of Miami, Miami, FL 33146, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tania","family":"Gensale","sequence":"additional","affiliation":[{"name":"IQVIA Laboratories, Laval, QC H7V 3S8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9354-0748","authenticated-orcid":false,"given":"Shannon","family":"Harris","sequence":"additional","affiliation":[{"name":"ILiAD Biotechnologies, Inc., Weston, FL 33331, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tina M.","family":"Green","sequence":"additional","affiliation":[{"name":"ILiAD Biotechnologies, Inc., Weston, FL 33331, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephanie","family":"Noviello","sequence":"additional","affiliation":[{"name":"ILiAD Biotechnologies, Inc., Weston, FL 33331, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Keith","family":"Rubin","sequence":"additional","affiliation":[{"name":"ILiAD Biotechnologies, Inc., Weston, FL 33331, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7295-7336","authenticated-orcid":false,"given":"Camille","family":"Locht","sequence":"additional","affiliation":[{"name":"CNRS, Inserm, CHU Lille, Institut Pasteur de Lille, U1019-UMR9017\u2013CIIL\u2014Centre for Infection and Immunity of Lille, University of Lille, F-59000 Lille, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Breeze","family":"Cavell","sequence":"additional","affiliation":[{"name":"UK Health Security Agency, Porton Down SP4 0JG, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2193-7954","authenticated-orcid":false,"given":"Andrew","family":"Gorringe","sequence":"additional","affiliation":[{"name":"UK Health Security Agency, Porton Down SP4 0JG, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Luc","family":"Gagnon","sequence":"additional","affiliation":[{"name":"IQVIA Laboratories, Laval, QC H7V 3S8, Canada"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,5,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"974","DOI":"10.1016\/S1473-3099(17)30390-0","article-title":"An Update of the Global Burden of Pertussis in Children Younger than 5 Years: A Modelling Study","volume":"17","author":"Yeung","year":"2017","journal-title":"Lancet Infect. 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