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<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="other" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Russian Journal of Infection and Immunity</journal-id><journal-title-group><journal-title xml:lang="en">Russian Journal of Infection and Immunity</journal-title><trans-title-group xml:lang="ru"><trans-title>Инфекция и иммунитет</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2220-7619</issn><issn publication-format="electronic">2313-7398</issn><publisher><publisher-name xml:lang="en">SPb RAACI</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">709</article-id><article-id pub-id-type="doi">10.15789/2220-7619-2019-5-6-763-772</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="article-type"><subject></subject></subj-group></article-categories><title-group><article-title xml:lang="en">Microneutralization reaction compared to hemagglutination inhibition assay to evaluate immunogenicity of influenza vaccines and influenza diagnostics</article-title><trans-title-group xml:lang="ru"><trans-title>Реакция микронейтрализации в сравнении с реакцией торможения гемагглютинации при оценке иммуногенности гриппозных вакцин и диагностике гриппа</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Krivitskaya</surname><given-names>V. Z.</given-names></name><name xml:lang="ru"><surname>Кривицкая</surname><given-names>В. З.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Vera Z. Krivitskaya, PhD, MD (Biology), Leading Researcher, Laboratory for the Study of Risk Factors for Influenza and ARVI</p><p>197376, St. Petersburg, Professor Popov str., 15/17.</p><p>Phone/fax: +7 (812) 499-15-29 (office); +7 921 886-37-95 (mobile).</p></bio><bio xml:lang="ru"><p>Кривицкая Вера Зорьевна, д.б.н., ведущий научный сотрудник лаборатории изучения факторов риска при гриппе и ОРВИ</p><p>197376, Санкт-Петербург, ул. Проф. Попова, 15/17.</p><p>Тел./факс: 8 (812) 499-15-29 (служебн.); 8 921 886-37-95 (моб.).</p></bio><email>vera.kriv@influenza.spb.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kuznecova</surname><given-names>E. V.</given-names></name><name xml:lang="ru"><surname>Кузнецова</surname><given-names>Е. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Senior Researcher, Laboratory for the Study of Risk Factors for Influenza and ARVI</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>к.б.н., старший научный сотрудник лаборатории изучения факторов риска при гриппе и ОРВИ</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Majorova</surname><given-names>V. G.</given-names></name><name xml:lang="ru"><surname>Майорова</surname><given-names>В. Г.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Senior Researcher, Laboratory for the Study of Risk Factors for Influenza and ARVI</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>старший научный сотрудник лаборатории изучения факторов риска при гриппе и ОРВИ</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Kadyrova</surname><given-names>R. A.</given-names></name><name xml:lang="ru"><surname>Кадырова</surname><given-names>Р. А.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Researcher, Laboratory of Cell Cultures</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>младший научный сотрудник лаборатории клеточных культур</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Lvov</surname><given-names>N. I.</given-names></name><name xml:lang="ru"><surname>Львов</surname><given-names>Н. И.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD, MD (Medicine), Assistant Professor, Professor of Department of Infectious Diseases</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>д.м.н., доцент, профессор кафедры инфекционных болезней</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Go</surname><given-names>A. A.</given-names></name><name xml:lang="ru"><surname>Го</surname><given-names>А. А.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Medicine), Infectious Disease Physician, Clinical Diagnostic Department</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>к.м.н., врач-инфекционист клинико-диагностического отделения</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff3"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Sominina</surname><given-names>A. A.</given-names></name><name xml:lang="ru"><surname>Соминина</surname><given-names>А. А.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD, MD (Medicine), Professor, Head of the Laboratory for the Study of Risk Factors for Influenza and ARVI</p><p>St. Petersburg</p></bio><bio xml:lang="ru"><p/><p>д.м.н., профессор, зав. лабораторией изучения факторов риска при гриппе и ОРВИ</p>Санкт-Петербург</bio><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Smorodintsev Research Institute of Influenza, Ministry of Health of the Russian Federation</institution></aff><aff><institution xml:lang="ru">ФГБУ НИИ гриппа им. А.А. Смородинцева МЗ РФ</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Kirov Military Medical Academy, Ministry of Defence of the Russian Federation</institution></aff><aff><institution xml:lang="ru">ФГБВОУ ВПО Военно-медицинская академия им. С.М. Кирова МО РФ</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">St. Petersburg Pasteur Institute</institution></aff><aff><institution xml:lang="ru">ФБУН НИИ эпидемиологии и микробиологии имени Пастера</institution></aff></aff-alternatives><pub-date date-type="pub" iso-8601-date="2019-12-01" publication-format="electronic"><day>01</day><month>12</month><year>2019</year></pub-date><volume>9</volume><issue>5-6</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>763</fpage><lpage>772</lpage><history><date date-type="received" iso-8601-date="2018-06-25"><day>25</day><month>06</month><year>2018</year></date><date date-type="accepted" iso-8601-date="2019-03-14"><day>14</day><month>03</month><year>2019</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2019, Krivitskaya V.Z., Kuznecova E.V., Majorova V.G., Kadyrova R.A., Lvov N.I., Go A.A., Sominina A.A.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2019, Кривицкая В.З., Кузнецова Е.В., Майорова В.Г., Кадырова Р.А., Львов Н.И., Го А.А., Соминина А.А.</copyright-statement><copyright-year>2019</copyright-year><copyright-holder xml:lang="en">Krivitskaya V.Z., Kuznecova E.V., Majorova V.G., Kadyrova R.A., Lvov N.I., Go A.A., Sominina A.A.</copyright-holder><copyright-holder xml:lang="ru">Кривицкая В.З., Кузнецова Е.В., Майорова В.Г., Кадырова Р.А., Львов Н.И., Го А.А., Соминина А.А.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://iimmun.ru/iimm/article/view/709">https://iimmun.ru/iimm/article/view/709</self-uri><abstract xml:lang="en"><p>The aim of this study was to compare the results of the hemagglutination inhibition test (HI-test) and microneutralization reaction in detection of antibodies to influenza A(H1N1), A(H1N1)pdm09, and A(H3N2) viruses in human sera, as well optimize microneutralization reaction conditions. The proposed variant of microneutralization reaction is based on detecting decreased influenza virus reproduction in infected MDCK cells in the presence of virus-specific serum antibodies. Virus reproduction was evaluated by enzyme-linked immunosorbent assay in 96-well cell culture plates using type-specific anti-influenza A viruse NP-protein monoclonal antibodies. In parallel, in microneutralization reaction and HI-test paired sera collected from 205 volunteers inoculated with inactivated seasonal influenza vaccines were analyzed, as well as from 117 adult patients with laboratory-confirmed influenza. The rationale for treatment of human serum with receptor-destroying enzyme (RDE) was proved not only for HI-test, but also for microneutralization reaction. Compared to HI-assay, the microneutralization reaction displayed higher sensitivity. According to microneutralization data, seroconversion rates and increase in antibody titer against influenza A viruses in both vaccinated and infected persons were superior to HI-test data by 1.4–2.5-fold. Moreover, higher sensitivity of this method was of great importance for the diagnostics of disease caused by new pathogens. The efficacy of influenza A(H1N1)pdm09 serodiagnostics in PCRpositive patients was 1.5 times higher based on microneutralization reaction vs. HI-assay data. According to the data from early studies, it is commonly believed that 1/40 titer of flu-specific antibodies detected by HI-test is set as protective. However, a consensus on protective level for virus-specific antibodies in neutralization reaction has not been established yet. It was found that serum antibody levels detected by the proposed version of microneutralization reaction were significantly higher than those in HI-assay. In the post vaccination sera collected from vaccinated volunteers, average titers of virus neutralizing antibodies corresponding to 1/40 in HI-test were 1/195, 1/203, and 1/ 426–1/430 for influenza A(H1N1), A(H1N1)pdm09 and A(H3N2), respectively, whereas in influenza patients they were 1/285, 1/215 and 1/488, respectively. Thus, it was suggested to consider a threshold value for “conditionally protective” level of neutralizing antibodies in adult vaccinated volunteers or infected patients, an average titer 1/160 for A(H1N1) and A(H1N1)pdm09 viruses, as well as 1/320 — for A(H3N2) virus, which agree with data published elsewhere.</p></abstract><trans-abstract xml:lang="ru"><p>Целью исследования являлось сравнение результатов реакции торможения гемагглютинации (РТГА) и реакции микронейтрализации при детекции антител к вирусам гриппа А(H1N1), A(H1N1)pdm09 и А(H3N2) в сыворотках людей, а также оптимизация условий постановки реакции микронейтрализации. Предложенный вариант реакции микронейтрализации основан на выявлении снижения репродукции вируса гриппа в инфицированных клетках MDCK в присутствии вирусспецифичных сывороточных антител. Репродукцию вирусов в клетках оценивали иммуноферментным методом в 96-луночных культуральных планшетах с помощью типоспецифичных моноклональных антител, направленных к NP-белку вирусов гриппа А. Параллельно в реакции микронейтрализации и РТГА были проанализированы парные сыворотки 205 волонтеров, привитых инактивированными сезонными гриппозными вакцинами, а также 117 взрослых пациентов, переболевших лабораторно подтвержденным гриппом. Доказана целесообразность обработки сывороток человека рецептор-разрушающим энзимом (RDE) при постановке не только РТГА, но и реакции микронейтрализации. Показана бόльшая чувствительность реакции микронейтрализации по сравнению с РТГА. По данным микронейтрализации показатели частоты сероконверсий и кратности прироста антител к вирусам гриппа А у вакцинированных и переболевших людей превышали в 1,4–2,5 раза результаты, полученные в РТГА. Более высокая чувствительность реакции микронейтрализации имела большое значение при расшифровке заболевания, вызванного новым патогеном. Эффективность серодиагностики гриппа A(H1N1)pdm09 у ПЦРположительных пациентов была в 1,5 раза выше по результатам реакция микронейтрализации по сравнению с РТГА. Согласно традиционным представлениям, основанным на результатах ранних работ, титр гриппспецифичных антител 1/40, выявленный в РТГА, считается защитным. При этом общепринятого протективного уровня вирусспецифичных антител для реакции нейтрализации до сих пор не установлено. Уровни антител в сыворотках, выявленные при использовании предложенного варианта реакции микронейтрализации, были значительно выше, чем по результатам РТГА. В поствакцинальных сыворотках привитых волонтеров среднегрупповые титры вируснейтрализующих антител, соответствующие 1/40 в РТГА, составили 1/195, 1/203 и 1/426–1/430 для вирусов гриппа A(Н1N1), A(Н1N1)pdm09 и A(Н3N2) соответственно. В сыворотках переболевших гриппом пациентов эти же показатели составили 1/285, 1/215 и 1/488. В соответствии с этим для реакции микронейтрализации порогами для «условно протективного» уровня антител у взрослых вакцинированных волонтеров или заболевших пациентов предложено считать в титры 1/160 для вирусов A(Н1N1) и A(Н1N1)pdm09, а также 1/320 для вируса A(Н3N2), что согласуется с данными других исследователей.</p></trans-abstract><kwd-group xml:lang="en"><kwd>microneutralization reaction</kwd><kwd>hemagglutination inhibition assay</kwd><kwd>influenza vaccines</kwd><kwd>adult patients</kwd><kwd>influenza A(H1N1)</kwd><kwd>influenza A(H3N2)</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>реакция микронейтрализации</kwd><kwd>реакция торможения гемагглютинации</kwd><kwd>гриппозные вакцины</kwd><kwd>взрослые пациенты</kwd><kwd>грипп A(H1N1)</kwd><kwd>грипп A(H3N2)</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>1. 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