Acta NaturaeActa NaturaeActa Naturae2075-8251Acta Naturae Ltd2787410.32607/actanaturae.27874Research ArticlesЭкспериментальные статьиResearch ArticleIsolation of monoclonal neutralizing single-domain antibodies against Clostridioides difficile toxin BПолучение моноклональных однодоменных антител, нейтрализующих действие токсина B Clostridioides difficileAlekseevaI. A.АлексееваИ. А.
Russian Federation
favorskaya@gamaleya.orgUngurA. S.УнгурА. С.
Russian Federation
favorskaya@gamaleya.orgFavorskayaI. A.ФаворскаяИ. А.
Russian Federation
favorskaya@gamaleya.orgTukhvatulinA. I.ТухватулинА. И.
Russian Federation
favorskaya@gamaleya.orgShcheblyakovD. V.ЩебляковД. В.
Russian Federation
favorskaya@gamaleya.orgKorobkovaA. I.КоробковаА. И.
Russian Federation
favorskaya@gamaleya.orgKomyakovaM. E.КомяковаМ. Е.
Russian Federation
favorskaya@gamaleya.orgVoroninaO. L.ВоронинаО. Л.
Russian Federation
favorskaya@gamaleya.orgRyzhovaN. N.РыжоваН. Н.
Russian Federation
favorskaya@gamaleya.orgErmolovaE. I.ЕрмоловаЕ. И.
Russian Federation
favorskaya@gamaleya.orgKundaM. S.КундаМ. С.
Russian Federation
favorskaya@gamaleya.orgLogunovD. Yu.ЛогуновД. Ю.
Russian Federation
favorskaya@gamaleya.orgBobrovaM. M.БоброваМ. М.
Russian Federation
favorskaya@gamaleya.orgMakarovV. V.МакаровВ. В.
Russian Federation
favorskaya@gamaleya.orgYudinS. M.ЮдинС. М.
Russian Federation
favorskaya@gamaleya.orgGintsburgA. L.ГинцбургА. Л.
Russian Federation
favorskaya@gamaleya.orgGamaleya National Research Center of Epidemiology and Microbiology of the Ministry of Health of the Russian FederationФедеральное государственное бюджетное учреждение «Национальный исследовательский центр эпидемиологии и микробиологии имени почетного академика Н.Ф. Гамалеи» Минздрава РоссииCentre for Strategic Planning and Management of Biomedical Health Risks of the Federal Medical and Biological AgencyФедеральное государственное бюджетное учреждение «Центр стратегического планирования и управления медико-биологическими рисками здоровью» Федерального медико-биологического агентства2307202618236440111202517042026Copyright ©; 2026, Alekseeva I.A., Ungur A.S., Favorskaya I.A., Tukhvatulin A.I., Shcheblyakov D.V., Korobkova A.I., Komyakova M.E., Voronina O.L., Ryzhova N.N., Ermolova E.I., Kunda M.S., Logunov D.Y., Bobrova M.M., Makarov V.V., Yudin S.M., Gintsburg A.L.Copyright ©; 2026, Алексеева И.А., Унгур А.С., Фаворская И.А., Тухватулин А.И., Щебляков Д.В., Коробкова А.И., Комякова М.Е., Воронина О.Л., Рыжова Н.Н., Ермолова Е.И., Кунда М.С., Логунов Д.Ю., Боброва М.М., Макаров В.В., Юдин С.М., Гинцбург А.Л.2026Alekseeva I.A., Ungur A.S., Favorskaya I.A., Tukhvatulin A.I., Shcheblyakov D.V., Korobkova A.I., Komyakova M.E., Voronina O.L., Ryzhova N.N., Ermolova E.I., Kunda M.S., Logunov D.Y., Bobrova M.M., Makarov V.V., Yudin S.M., Gintsburg A.L.Алексеева И.А., Унгур А.С., Фаворская И.А., Тухватулин А.И., Щебляков Д.В., Коробкова А.И., Комякова М.Е., Воронина О.Л., Рыжова Н.Н., Ермолова Е.И., Кунда М.С., Логунов Д.Ю., Боброва М.М., Макаров В.В., Юдин С.М., Гинцбург А.Л.https://creativecommons.org/licenses/by/4.0https://actanaturae.ru/2075-8251/article/view/27874

The Clostridioides difficile infection (CDI) is one of the most common nosocomial infections around. The key pathogenicity factors of this bacterium include the toxins A and B that cause the disease symptoms. Neutralization of these toxins is one of the promising strategies for CDI treatment. Here, we isolated a panel of single-domain antibodies to the toxin B CROPs domain. Two antibodies, TB5A7 and TB4A8, exhibiting potent neutralizing activity were modified to produce homodimeric forms. The TB5A7 and TB4A8 dimers were characterized by enhanced neutralizing activity and protected animals from a toxin B lethal challenge. The obtained antibodies may be used to develop new agents for CDI treatment.

Clostridioides difficile-ассоциированная инфекция (CDI) является одной из наиболее частых нозокомиальных инфекций. Ключевые факторы патогенности этой бактерии включают токсины A и B, опосредующие развитие симптомов заболевания. Нейтрализация вырабатываемых токсинов – одна из перспективных стратегий терапии CDI. В представленной работе получена панель однодоменных антител к домену CROPs токсина В. Два клона антител, TB5A7 и TB4A8, обладали высокой нейтрализующей активностью и были модифицированы с получением гомодимерных форм. Димеры TB5A7 и TB4A8 характеризовались улучшенными показателями нейтрализующей активности и защищали экспериментальных животных от летальной дозы токсина B. Полученные антитела в дальнейшем могут быть использованы для разработки новых средств терапии CDI.

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