{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T19:05:37Z","timestamp":1791140737497,"version":"4.1.0"},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,7,17]],"date-time":"2018-07-17T00:00:00Z","timestamp":1531785600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R01AI110627"],"award-info":[{"award-number":["R01AI110627"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100010269","name":"Wellcome Trust","doi-asserted-by":"publisher","award":["Strategic Translation Grant"],"award-info":[{"award-number":["Strategic Translation Grant"]}],"id":[{"id":"10.13039\/100010269","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>Typhoid fever due to Salmonella Typhi and invasive nontyphoidal Salmonella (iNTS) infections caused by serovars Enteritidis (SE) and Typhimurium (STm) are major pediatric health problems in sub-Saharan Africa. Typhoid has high complication rates, and iNTS infections have high case fatality rates; moreover, emerging antimicrobial resistance is diminishing treatment options. Vi capsule-based typhoid conjugate vaccine (Typbar-TCV\u2122), licensed in India and pre-qualified by the World Health Organization, elicits durable immunity when administered to infants, but no iNTS vaccines are licensed or imminent. We have developed monovalent SE and STm glycoconjugate vaccines based on coupling lipopolysaccharide-derived core-O polysaccharide (COPS) to phase 1 flagellin protein (FliC) from the homologous serovar. Herein, we report the immunogenicity of multivalent formulations of iNTS COPS:FliC conjugates with Typbar-TCV\u2122. Rabbits immunized with the trivalent typhoid-iNTS glycoconjugate vaccine generated high titers of serum IgG antibody to all three polysaccharide antigens for which anti-COPS IgG antibodies were directed primarily against serogroup-specific OPS epitopes. Responses to SE and STm FliC were lower relative to anti-COPS titers. Post-vaccination rabbit sera mediated bactericidal activity in-vitro, and protected mice after passive transfer against challenge with virulent SE or STm Malian blood isolates. These results support accelerated progression to clinical trials.<\/jats:p>","DOI":"10.3390\/molecules23071749","type":"journal-article","created":{"date-parts":[[2018,7,18]],"date-time":"2018-07-18T08:45:42Z","timestamp":1531903542000},"page":"1749","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":33,"title":["Immunogenicity and Induction of Functional Antibodies in Rabbits Immunized with a Trivalent Typhoid-Invasive Nontyphoidal Salmonella Glycoconjugate Formulation"],"prefix":"10.3390","volume":"23","author":[{"given":"Scott M.","family":"Baliban","sequence":"first","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jessica C.","family":"Allen","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Brittany","family":"Curtis","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed N.","family":"Amin","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andrew","family":"Lees","sequence":"additional","affiliation":[{"name":"Fina Biosolutions LLC, 9430 Key West Ave. Suite 200, Rockville, MD 20850, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"R. Nageswara","family":"Rao","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gangadhara","family":"Naidu","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ramasamy","family":"Venkatesan","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D. Yogeswara","family":"Rao","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Vadrevu Krishna","family":"Mohan","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Krishna M.","family":"Ella","sequence":"additional","affiliation":[{"name":"Bharat Biotech International Limited, Hyderabad 500 078, Telangana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Myron M.","family":"Levine","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Raphael","family":"Simon","sequence":"additional","affiliation":[{"name":"Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2018,7,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/S0580-9517(08)70457-4","article-title":"Serology of Salmonella","volume":"Volume 15","author":"Bergan","year":"1984","journal-title":"Methods in Microbiology"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"e310","DOI":"10.1016\/S2214-109X(17)30022-0","article-title":"Incidence of invasive Salmonella disease in sub-Saharan Africa: a multicentre population-based surveillance study","volume":"5","author":"Marks","year":"2017","journal-title":"Lancet Glob. 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