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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="research-article" 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">1744</article-id><article-id pub-id-type="doi">10.15789/2220-7619-GPO-1744</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>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">Genetic polymorphisms of <italic>helicobacter pylori</italic> clinical isolates in St. Petersburg, Russia</article-title><trans-title-group xml:lang="ru"><trans-title>Геномный полиморфизм клинических изолятов <italic>helicobacter pylori</italic> в Санкт-Петербурге, Россия</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9340-4132</contrib-id><name-alternatives><name xml:lang="en"><surname>Svarval</surname><given-names>A. V.</given-names></name><name xml:lang="ru"><surname>Сварваль</surname><given-names>А. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Medicine), Senior Researcher, Head of the Pathogens Identification Laboratory</p></bio><bio xml:lang="ru"><p>к.м.н., старший научный сотрудник, зав. лабораторией идентификации патогенов</p></bio><email>alena.svarval@mail.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-3199-8689</contrib-id><name-alternatives><name xml:lang="en"><surname>Starkova</surname><given-names>Daria A.</given-names></name><name xml:lang="ru"><surname>Старкова</surname><given-names>Дарья Андреевна</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD (Biology), Senior Researcher of the Pathogens Identification Laboratory, Researcher of the Laboratory of Molecular Epidemiology and Evolutionary Genetics</p></bio><bio xml:lang="ru"><p>к.б.н., старший научный сотрудник лаборатории идентификации патогенов, научный сотрудник лаборатории молекулярной эпидемиологии и эволюционной генетики</p></bio><email>dariastarkova13@gmail.com</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7661-3725</contrib-id><name-alternatives><name xml:lang="en"><surname>Ferman</surname><given-names>R. S.</given-names></name><name xml:lang="ru"><surname>Ферман</surname><given-names>Р. С.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>Junior Researcher, Pathogens Identification Laboratory</p></bio><bio xml:lang="ru"><p>младший научный сотрудник лаборатории идентификации патогенов</p></bio><email>laborimmun@mail.ru</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-0830-5808</contrib-id><name-alternatives><name xml:lang="en"><surname>Narvskaya</surname><given-names>O. V.</given-names></name><name xml:lang="ru"><surname>Нарвская</surname><given-names>О. В.</given-names></name></name-alternatives><address><country country="RU">Russian Federation</country></address><bio xml:lang="en"><p>PhD, MD (Medicine), Professor, Leading Researcher, Laboratory of Molecular Epidemiology and Evolutionary Genetics, Academic Adviser</p></bio><bio xml:lang="ru"><p>д.м.н., профессор, ведущий научный сотрудник лаборатории молекулярной эпидемиологии и эволюционной генетики, научный консультант</p></bio><email>onarvskaya@gmail.com</email><xref ref-type="aff" rid="aff1"/><xref ref-type="aff" rid="aff2"/></contrib></contrib-group><aff-alternatives id="aff1"><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><aff-alternatives id="aff2"><aff><institution xml:lang="en">St. Petersburg State Research Institute of Phthisiopulmonology of the Ministry of Health of Russia</institution></aff><aff><institution xml:lang="ru">ФГБУ СПб НИИ фтизиопульмонологии Минздрава РФ</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2022-04-12" publication-format="electronic"><day>12</day><month>04</month><year>2022</year></pub-date><pub-date date-type="pub" iso-8601-date="2022-05-13" publication-format="electronic"><day>13</day><month>05</month><year>2022</year></pub-date><volume>12</volume><issue>2</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>315</fpage><lpage>322</lpage><history><date date-type="received" iso-8601-date="2021-06-03"><day>03</day><month>06</month><year>2021</year></date><date date-type="accepted" iso-8601-date="2022-01-22"><day>22</day><month>01</month><year>2022</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2022, Svarval A.V., Starkova D.A., Ferman R.S., Narvskaya O.V.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2022, Сварваль А.В., Старкова Д.А., Ферман Р.С., Нарвская О.В.</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="en">Svarval A.V., Starkova D.A., Ferman R.S., Narvskaya O.V.</copyright-holder><copyright-holder xml:lang="ru">Сварваль А.В., Старкова Д.А., Ферман Р.С., Нарвская О.В.</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/1744">https://iimmun.ru/iimm/article/view/1744</self-uri><abstract xml:lang="en"><p><italic>Introduction.</italic> <italic>Helicobacter pylori</italic> was proved to be the principal causative agent of gastroduodenal disorders in human. Although Russian Federation is among the countries with a high prevalence of <italic>H. pylori</italic> infection (60–90%), currently there is a very limited number of studies evaluating <italic>H. pylori</italic> genotypes in Russia. <italic>Objective.</italic> Based on the assessment of virulence-associated <italic>cagA, oipA</italic>, and <italic>vacA</italic> genes, our study was aimed to determine <italic>H. pylori</italic> genotypes associated with the clinical outcomes in patients with <italic>H. pylori</italic> infection in St. Petersburg, Northwest Russia. <italic>Materials and methods.</italic> Using PCR for the detection of <italic>cagA, oipA</italic>, and <italic>vacA</italic> s, m, i allelic variants, we analyzed 61 <italic>H. pylori</italic> isolates isolated and cultured from biopsies collected during endoscopy of patients with chronic gastritis (G), duodenal ulcer (DU), and gastric cancer (GC). <italic>Results.</italic> The genetic diversity of <italic>H. pylori</italic> clinical isolates has been revealed (HGDI 0.88): 41 (67%) of 61 <italic>H. pylori</italic> isolates were <italic>cagA</italic>-positive, 38 (62%) — <italic>oipA</italic>-positive. The proportions of <italic>cagA+</italic> isolates differed in patients with G (56.7%) and DU (80.9%) (p = 0.06). The s, m, and i allelic variants of the <italic>vacA</italic> gene were detected in all strains, although the <italic>vacA</italic> s1 allele was significantly dominant in patients with DU (95.2%) rather than with G (64.9%) (p = 0.01). The <italic>vacA</italic> alleles m1 and i1 in the isolates from patients with G and DU were found in almost equal proportions: 45.9% and 42.8% for m1 allele, 45.9% and 47.6% for i1 allele, respectively. Seven isolates (11.5%) were positive for different mixed combinations of vacA alleles s, m, and i. Noteworthy, all <italic>vacA</italic> s2 strains were <italic>cagA</italic>-negative and had the m2 allele. <italic>OipA+</italic> strains were found in almost equal proportions in patients with G (62.2%) and DU (57.1%) (p = 0.71). All three <italic>cagA</italic>- and <italic>oipA</italic>-positive isolates from patients with GC carried <italic>vacA</italic> s1/m1/i1 alleles. Different combinations of virulence-associated determinants constituted 17 genetic profiles. The most common combined genotype<italic> cagA+/oipA+/vacA </italic>s1/m1/i1 comprised 18 (29.5%) <italic>H. pylori</italic> isolates. <italic>Conclusion.</italic> We have determined predominant genotypes in the <italic>H. pylori</italic> population in the Northwest of Russia. The significant association between <italic>vacA </italic>s1 genotype of the pathogen and clinical manifestations of <italic>H. pylori</italic> infection has been established in our study.</p></abstract><trans-abstract xml:lang="ru"><p><italic>Введение. Helicobacter pylori</italic> — основной возбудитель гастродуоденальных заболеваний человека. Несмотря на то что Российская Федерация относится к числу стран с высоким уровнем распространенности инфекции <italic>H. pylori</italic> (60–90%), в настоящее время довольно ограниченное количество исследований посвящено генетическому разнообразию <italic>H. pylori </italic>в России. Цель — на основании оценки генов вирулентности <italic>cagA, oipA</italic> и <italic>vacA</italic> изучить геномный полиморфизм клинических изолятов <italic>H. pylori</italic>, полученных от различных групп больных на территории Санкт-Петербурга, Россия. <italic>Материалы и методы.</italic> Изучен 61 штамм <italic>H. pylori</italic>, выделенных от пациентов с хроническим гастритом (ХГ), язвой двенадцатиперстной кишки (ЯДК) и раком желудка (РЖ). Стандартный метод ПЦР использовали для детекции генов <italic>cagA, oipA</italic> и аллельных вариантов гена <italic>vacA</italic> (s, m, i). <italic>Результаты. </italic>Установлена генетическая неоднородность 61 штамма <italic>H. pylori</italic> (HGDI 0.88): 41 (67%) штамм был <italic>cagA</italic>-позитивным, 38 (62%) были <italic>oipA</italic>-позитивными. Доли <italic>cagA+</italic> штаммов различались у пациентов с ХГ (56,7%) и ЯДК (80,9%) (p = 0,06). Ген <italic>vасА</italic> в различных s-, m-, i-аллельных вариантах выявлен у всех штаммов. Доля штаммов аллельного варианта <italic>vacA</italic> s1 существенно превалировала у пациентов с ЯДК (95,2%) по сравнению с больными ХГ (64,9%) (p = 0,01). Аллели <italic>vacA</italic> m1 и i1 у штаммов от пациентов с ХГ и ЯДК были обнаружены почти в равных пропорциях: 45,9 и 42,8% для аллеля m1, 45,9 и 47,6% для аллеля i1 соответственно. Семь штаммов (11,5%) имели смешанные s, m и i генотипы. Все штаммы аллеля <italic>vacA</italic> s2 являлись <italic>cagA</italic>-негативными и несли аллель m2. Штаммы <italic>о</italic><italic>ipA+</italic> практически в равных долях были обнаружены у больных ХГ (62,2%) и ЯДК (57,1%) (р = 0,71). Все три штамма от пациентов с РЖ являлись <italic>cagA</italic>- и <italic>oipA</italic>-позитивными и несли аллели <italic>vacA</italic> s1/m1/i1. Анализ результатов генотипирования позволил выявить 17 вариантов профилей (комбинированных генотипов). Наиболее распространенный комбинированный генотип <italic>cagA+/oipA+/vacA </italic>s1/m1/i1 включал 18 (29,5%) штаммов <italic>H. pylori</italic>. <italic>Выводы.</italic> В результате анализа геномного полиморфизма клинических изолятов <italic>H. pylori</italic>, выделенных от больных хеликобактериозом, были выявлены доминирующие генотипы популяции <italic>H. pylori</italic> в Санкт-Петербурге, Россия. Установлена связь генотипа <italic>vacA </italic>s1 возбудителя с клиническими проявлениями инфекции <italic>H. pylori.</italic></p></trans-abstract><kwd-group xml:lang="en"><kwd>Helicobacter pylori</kwd><kwd>cagA gene</kwd><kwd>vacA gene</kwd><kwd>oipA gene</kwd><kwd>gastritis</kwd><kwd>duodenal ulcer</kwd><kwd>gastric cancer</kwd><kwd>virulence determinants</kwd><kwd>genomic polymorphism</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>Helicobacter pylori</kwd><kwd>ген cagA</kwd><kwd>ген vacA</kwd><kwd>ген oipA</kwd><kwd>гастрит</kwd><kwd>язва двенадцатиперстной кишки</kwd><kwd>рак желудка</kwd><kwd>гены вирулентности</kwd><kwd>геномный полиморфизм</kwd></kwd-group><funding-group/></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>Ахтереева А.Р., Давидюк Ю.Н., Файзуллина Р.А., Ивановская К.А., Сафин А.Г., Сафина Д.Д., Абдулхаков С.Р. 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