{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:13:07Z","timestamp":1787029987945,"version":"build-2736575974"},"reference-count":51,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2020,3,29]],"date-time":"2020-03-29T00:00:00Z","timestamp":1585440000000},"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":["HHSN272201400021C"],"award-info":[{"award-number":["HHSN272201400021C"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["AI125190"],"award-info":[{"award-number":["AI125190"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["R44AI141282"],"award-info":[{"award-number":["R44AI141282"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxins"],"abstract":"<jats:p>PB10 IgG1, a monoclonal antibody (MAb) directed against an immunodominant epitope on the enzymatic subunit (RTA) of ricin toxin (RT), has been shown to passively protect mice and non-human primates from an aerosolized lethal-dose RT challenge. However, it was recently demonstrated that the therapeutic efficacy of PB10 IgG1 is significantly improved when co-administered with a second MAb, SylH3, targeting RT\u2019s binding subunit (RTB). Here we report that the PB10\/SylH3 cocktail is also superior to PB10 alone when used as a pre-exposure prophylactic (PrEP) in a mouse model of intranasal RT challenge. The benefit of the PB10\/SylH3 cocktail prompted us to engineer a humanized IgG1 version of SylH3 (huSylH3). The huPB10\/huSylH3 cocktail proved highly efficacious in the mouse model, thereby opening the door to future testing in non-human primates.<\/jats:p>","DOI":"10.3390\/toxins12040215","type":"journal-article","created":{"date-parts":[[2020,4,2]],"date-time":"2020-04-02T13:39:34Z","timestamp":1585834774000},"page":"215","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":22,"title":["A Humanized Monoclonal Antibody Cocktail to Prevent Pulmonary Ricin Intoxication"],"prefix":"10.3390","volume":"12","author":[{"given":"Yinghui","family":"Rong","sequence":"first","affiliation":[{"name":"Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michael","family":"Pauly","sequence":"additional","affiliation":[{"name":"Mapp Biopharmaceutical, Inc. 6160 Lusk Blvd, San Diego, CA 92121, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adrian","family":"Guthals","sequence":"additional","affiliation":[{"name":"Mapp Biopharmaceutical, Inc. 6160 Lusk Blvd, San Diego, CA 92121, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henry","family":"Pham","sequence":"additional","affiliation":[{"name":"Mapp Biopharmaceutical, Inc. 6160 Lusk Blvd, San Diego, CA 92121, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dylan","family":"Ehrbar","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6857-1024","authenticated-orcid":false,"given":"Larry","family":"Zeitlin","sequence":"additional","affiliation":[{"name":"Mapp Biopharmaceutical, Inc. 6160 Lusk Blvd, San Diego, CA 92121, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5083-8640","authenticated-orcid":false,"given":"Nicholas J.","family":"Mantis","sequence":"additional","affiliation":[{"name":"Division of Infectious Diseases, Wadsworth Center, New York State Department of Health, Albany, NY 12208, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,3,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e59","DOI":"10.1093\/milmed\/usx004","article-title":"Beyond the Dirty Dozen: A Proposed Methodology for Assessing Future Bioweapon Threats","volume":"183","author":"Cieslak","year":"2018","journal-title":"Mil. 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