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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">biopreparat</journal-id><journal-title-group><journal-title xml:lang="ru">БИОпрепараты. Профилактика, диагностика, лечение</journal-title><trans-title-group xml:lang="en"><trans-title>Biological Products. Prevention, Diagnosis, Treatment</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2221-996X</issn><issn pub-type="epub">2619-1156</issn><publisher><publisher-name>Scientific Centre for Expert Evaluation of Medicinal Products</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.30895/2221-996X-2022-450</article-id><article-id custom-type="elpub" pub-id-type="custom">biopreparat-450</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>Статьи</subject></subj-group></article-categories><title-group><article-title>Получение и характеристика гомодимерной формы RBD S-белка SARS-CoV-2, обладающей повышенной авидностью к специфическим антителам</article-title><trans-title-group xml:lang="en"><trans-title>Production and characterisation of a SARS-CoV-2 S-protein RBD homodimer with increased avidity for specific antibodies</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3776-3856</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Деркаев</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Derkaev</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Деркаев Артем Алексеевич</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Artem A. Derkaev</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">derkaev.a@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2687-5185</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Рябова</surname><given-names>Е. И.</given-names></name><name name-style="western" xml:lang="en"><surname>Ryabova</surname><given-names>E. I.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Рябова Екатерина Игоревна</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Ekaterina I. Ryabova</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">ryabovaei96@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-4130-177X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Прокофьев</surname><given-names>В. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Prokofiev</surname><given-names>V. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Прокофьев Владимир Владимирович</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Vladimir V. Prokofiev</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">vladimir.prokofev2609@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-0639-8390</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Фаворская</surname><given-names>И. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Favorskaya</surname><given-names>I. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Фаворская Ирина Алексеевна, канд. биол. наук</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Irina A. Favorskaya, Cand. Sci. (Biol.)</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">irina.favorskaya@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-3299-4818</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Гроусова</surname><given-names>Д. М.</given-names></name><name name-style="western" xml:lang="en"><surname>Grousova</surname><given-names>D. M.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Гроусова Дарья Михайловна</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Daria M. Grousova</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">dgrousova@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2063-2449</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Есмагамбетов</surname><given-names>И. Б.</given-names></name><name name-style="western" xml:lang="en"><surname>Esmagambetov</surname><given-names>I. B.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Есмагамбетов Ильяс Булатович, канд. биол. наук</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Ilias B. Esmagambetov, Cand. Sci. (Biol.)</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">esmagambetovib@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2548-6142</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Должикова</surname><given-names>И. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Dolzhikova</surname><given-names>I. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Должикова Инна Вадимовна, канд. биол. наук</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Inna V. Dolzhikova, Cand. Sci. (Biol.)</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">dolzhikova@gamaleya.org</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-1289-3411</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Щебляков</surname><given-names>Д. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Shcheblyakov</surname><given-names>D. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Щебляков Дмитрий Викторович, канд. биол. наук</p><p>ул. Гамалеи, д. 18, Москва, 123098</p></bio><bio xml:lang="en"><p>Dmitry V. Shcheblyakov. Cand. Sci. (Biol.)</p><p>18 Gamaleya St., Moscow 123098</p></bio><email xlink:type="simple">sdmitryv@yahoo.com</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Федеральное государственное бюджетное учреждение «Национальный исследовательский центр эпидемиологии и микробиологии имени почетного академика Н.Ф. Гамалеи» Министерства здравоохранения Российской Федерации</institution><country>Россия</country></aff><aff xml:lang="en"><institution>N.F. Gamaleya National Research Center for Epidemiology and Microbiology</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>02</day><month>01</month><year>2023</year></pub-date><volume>23</volume><issue>1</issue><issue-title>Вопросы разработки новых противовирусных вакцин</issue-title><fpage>76</fpage><lpage>89</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Деркаев А.А., Рябова Е.И., Прокофьев В.В., Фаворская И.А., Гроусова Д.М., Есмагамбетов И.Б., Должикова И.В., Щебляков Д.В., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Деркаев А.А., Рябова Е.И., Прокофьев В.В., Фаворская И.А., Гроусова Д.М., Есмагамбетов И.Б., Должикова И.В., Щебляков Д.В.</copyright-holder><copyright-holder xml:lang="en">Derkaev A.A., Ryabova E.I., Prokofiev V.V., Favorskaya I.A., Grousova D.M., Esmagambetov I.B., Dolzhikova I.V., Shcheblyakov D.V.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://www.biopreparations.ru/jour/article/view/450">https://www.biopreparations.ru/jour/article/view/450</self-uri><abstract><p>Важным параметром, оцениваемым при мониторинге иммунной прослойки у населения и эффективности вакцинации населения, является уровень вируснейтрализующих антител. Разработка подхода к выявлению вируснейтрализующих антител к вирусу SARS-CoV-2 с помощью безопасного, простого и быстрого метода, не требующего использования живых вирусов, имеет большое значение для борьбы с пандемией COVID-19. Для разработки тест-систем для проведения иммуноферментного анализа (ИФА), детектирующих потенциально вируснейтрализующие антитела, необходимо получение высокоочищенного рекомбинантного рецептор-связывающего домена (RBD) S-белка, обладающего высокой авидностью к специфическим антителам.</p><sec><title>Цель работы</title><p>Цель работы: получение и характеристика гомодимерной формы RBD S-белка вируса SARS-CoV-2, а также клеточной линии, продуцирующей рекомбинантный RBD, для создания ИФА тест-системы для выявления потенциально вируснейтрализующих антител.</p></sec><sec><title>Материалы и методы</title><p>Материалы и методы: дизайн генетической конструкции проводили in silico. Стабильную клеточную линию получали при помощи трансфекции клеток CHO-S, селекции на антибиотике и отбора оптимального клона. Рекомбинантный RBD очищали с использованием хроматографических методов, получали мономерную и гомодимерную формы RBD. Активность полученных форм анализировали с использованием методов Вестерн-блот, биослойной интерферометрии и непрямго ИФА. Для анализа использовали моноклональные антитела GamXRH19, GamP2C5 и h6g3, а также образцы сывороток крови добровольцев, вакцинированных препаратом Гам-КОВИД-Вак, и невакцинированных добровольцев.</p></sec><sec><title>Результаты</title><p>Результаты: получена клеточная линия CHO-S, стабильно продуцирующая рекомбинантный RBD S-белка вируса SARS-CoV-2. Показано, что при культивировании данной клеточной линии в режиме fed-batch более 7 суток рекомбинантный RBD способен образовывать гомодимеры за счет наличия неспаренных цистеинов. Количественный выход очищенного рекомбинантного RBD из культуральной жидкости составил 30–50 мг/л. Мономерная и гомодимерная формы RBD были разделены при помощи гель-фильтрации и охарактеризованы по способности взаимодействовать со специфическими моноклональными антителами, а также сыворотками крови от вакцинированных добровольцев. Продемонстрировано, что именно гомодимерная форма рекомбинантного RBD обладает повышенной авидностью к моноклональным антителам и антителам в сыворотке крови вакцинированных.</p></sec><sec><title>Выводы</title><p>Выводы: гомодимерная форма рекомбинантного RBD может являться более предпочтительной для анализа уровня антител к рецептор-связывающему домену S-белка вируса SARS-CoV-2.</p></sec></abstract><trans-abstract xml:lang="en"><p>Monitoring of the proportion of immune individuals and the effectiveness of vaccination in a population involves evaluation of several important parameters, including the level of virus-neutralising antibodies. In order to combat the COVID-19 pandemic, it is essential to develop approaches to detecting SARS-CoV-2 neutralising antibodies by safe, simple and rapid methods that do not require live viruses. To develop a test system for enzyme-linked immunosorbent assay (ELISA) that detects potential neutralising antibodies, it is necessary to obtain a highly purified recombinant receptor-binding domain (RBD) of the spike (S) protein with high avidity for specific antibodies.</p><p>The aim of the study was to obtain and characterise a SARS-CoV-2 S-protein RBD homodimer and a recombinant RBD-expressing cell line, as well as to create an ELISA system for detecting potential neutralising antibodies.</p><sec><title>Materials and methods</title><p>Materials and methods: the genetic construct was designed in silico. To generate a stable producer cell line, the authors transfected CHO-S cells, subjected them to antibiotic pressure, and selected the optimal clone. To isolate monomeric and homodimeric RBD forms, the authors purified the recombinant RBD by chromatographic methods. Further, they analysed the activity of the RBD forms by Western blotting, bio-layer interferometry, and indirect ELISA. The analysis involved mono clonal antibodies GamXRH19, GamP2C5, and h6g3, as well as serum samples from volunteers vaccinated with Gam-COVID-Vac (Sputnik V) and unvaccinated ones.</p></sec><sec><title>Results</title><p>Results: the authors produced the CHO-S cell line for stable expression of the recombinant SARS-CoV-2 S-protein RBD. The study demonstrated the recombinant RBD’s ability to homodimerise after fed-batch cultivation of the cell line for more than 7 days due to the presence of unpaired cysteines. The purified recombinant RBD yield from culture broth was 30–50 mg/L. Monomeric and homodimeric RBD forms were separated using gel-filtration chromatography and characterised by their ability to interact with specific monoclonal antibodies, as well as with serum samples from vaccinated volunteers. The homodimeric recombinant RBD showed increased avidity for both monoclonal and immune sera antibodies.</p></sec><sec><title>Conclusions</title><p>Conclusions: the homodimeric recombinant RBD may be more preferable for the analysis of levels of antibodies to the receptor-binding domain of the SARS-CoV-2 S protein.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>рекомбинантный белок</kwd><kwd>коронавирусная инфекция</kwd><kwd>рецептор-связывающий домен</kwd><kwd>SARS-CoV-2</kwd><kwd>авидность</kwd></kwd-group><kwd-group xml:lang="en"><kwd>recombinant protein</kwd><kwd>coronavirus infection</kwd><kwd>receptor-binding domain</kwd><kwd>SARS-CoV-2</kwd><kwd>avidity</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Работа выполнена в рамках гранта № 01-04-413 от 28.04.2020. Департамента здравоохранения города Москвы «Создание тест-системы для оценки активности плазмы крови «SARS-CoV-2-RBD-ИФА-Гамалеи».</funding-statement><funding-statement xml:lang="en">The study was supported by grant No. 01-04-413 “Development of the SARS-CoV-2-RBD-ELISA-Gamaleya test system for plasma activity assessment” of 28.04.2020 by the Moscow Department of Health.</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Yang Y, Du L. SARS-CoV-2 spike protein: a key target for eliciting persistent neutralizing antibodies. Signal Transduct Target Ther. 2021;6(1):95. https://doi.org/10.1038/s41392-021-00523-5</mixed-citation><mixed-citation xml:lang="en">Yang Y, Du L. SARS-CoV-2 spike protein: a key target for eliciting persistent neutralizing antibodies. 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