biobБиобезопасность и БиотехнологияBiosafety and Biotechnology2707-72412957-5702Научно-исследовательский институт проблем биологической безопасности10.58318/2957-5702-2026-26-17-39biob-255Research ArticleСТАТЬИArticlesКУЛЬТИВИРОВАНИЕ TREPONEMA PALLIDUM IN VITRO: ОТ КРОЛИЧЬЕЙ МОДЕЛИ К ЧЕЛОВЕЧЕСКИМ КЛЕТОЧНЫМ СИСТЕМАМIN VITRO CULTIVATION OF TREPONEMA PALLIDUM: FROM THE RABBIT MODEL TO HUMAN CELL-BASED SYSTEMShttps://orcid.org/0000-0002-6593-0271НахановА. К.NakhanovA. K.

Наханов Азиз Куралбаевич, кандитат биологических наук, заведующий лабораторией

Гвардейский 

Guardeyskiy 

a.nakhanov@biosafety.kzhttps://orcid.org/0009-0005-2630-8489КокановС. К.KokanovS. K.

Коканов Сабит Кабдышевич, кандитат ветеринарных наук, старший научный сотрудник 

Гвардейский 

Guardeyskiy 

s.kokanov@biosafety.kzhttps://orcid.org/0000-0003-3312-4045ЕспембетовБ. А.YespembetovB. A.

Еспембетов Болат Аманбаевич, кандидат ветеринарных наук, профеcсор, заведующий лабораторией

Гвардейский 

Guardeyskiy 

b.yespembetov@biosafety.kzhttps://orcid.org/0000-0002-4361-5676СырымН. С.SyrymN. S.

Сырым Назым Сырымовна, кандидат ветеринарных наук, профессор, главный научный сотрудник

Гвардейский 

Guardeyskiy 

n.syrym@biosafety.kzhttps://orcid.org/0000-0003-2077-7063ТеребайА. А.TerebaiA. A.

Теребай Айбол Айдосұлы, магистр, младший научный сотрудник 

Гвардейский 

Guardeyskiy 

a.terebay@biosafety.kzМараховскаяЛ. Г.MarakhovskayaL. G.

Мараховская Любовь Геннадьевна, старший лаборант

Гвардейский 

Guardeyskiy 

l.marahovskaya@biosafety.kzТОО «Научно-исследовательский институт проблем биологической безопасности», Национальный холдинг «QazBioPharm»КазахстанLLP «Research Institute for Biological Safety Problems», National holding «QazBioPharm»Kazakhstan2026240920261261739Copyright © Наханов А.К., Коканов С.К., Еспембетов Б.А., Сырым Н.С., Теребай А.А., Мараховская Л.Г., 20262026Наханов А.К., Коканов С.К., Еспембетов Б.А., Сырым Н.С., Теребай А.А., Мараховская Л.Г.Nakhanov A.K., Kokanov S.K., Yespembetov B.A., Syrym N.S., Terebai A.A., Marakhovskaya L.G.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://journal.biosafety.kz/jour/article/view/255

Treponema pallidum subsp. pallidum является возбудителем сифилиса - социально значимой инфекции человека, заболеваемость которой сохраняет тенденцию к росту во многих регионах мира. Несмотря на наличие эффективной антибактериальной терапии, изучение биологии данного патогена длительное время было ограничено невозможностью его устойчивого культивирования в искусственных условиях. Исторически поддержание лабораторных штаммов T. pallidum осуществлялось преимущественно путем интратестикулярного пассирования на лабораторных кроликах, что сопровождалось биоэтическими, технологическими и регуляторными ограничениями. Цель обзора - систематизировать современные данные о развитии систем культивирования T. pallidum in vitro: от кроличьей модели и ранних тканевых культур до платформы Sf1Ep, прямого выделения современных клинических штаммов и появления человеческих клеточных систем. В обзоре рассмотрены биологические причины трудности культивирования T. pallidum, включая редуцированный геном, ограниченные метаболические возможности, зависимость от клеткихозяина и чувствительность к кислороду. Показано, что система долгосрочного сокультивирования с эпителиальными клетками кролика Sf1Ep в среде TpCM-2 стала ключевым технологическим этапом в экспериментальной трепонемологии. Последующие исследования расширили спектр культивируемых штаммов, продемонстрировали возможность прямого выделения современных изолятов от пациентов и открыли перспективу использования человеческих фибробластных клеточных систем. Сделан вывод, что культивирование T. pallidum in vitro следует рассматривать как перспективную научно-технологическую платформу для изучения физиологии возбудителя, взаимодействия с клетками хозяина, оценки антибиотикочувствительности, снижения зависимости от животных моделей и развития биобезопасных экспериментальных подходов.

Treponema pallidum subsp. pallidum is the causative agent of syphilis, a socially significant human infection whose incidence continues to increase in many regions of the world. Despite the availability of effective antibacterial therapy, investigation of the biology of this pathogen has long been limited by the inability to maintain its stable growth under artificial conditions. Historically, laboratory strains of T. pallidum have been maintained mainly by intratesticular passage in laboratory rabbits, which is associated with bioethical, technological and regulatory limitations. The aim of this review is to systematize current data on the development of T. pallidum in vitro cultivation systems, from the rabbit model and early tissue cultures to the Sf1Ep platform, direct isolation of modern clinical strains and the emergence of human cell-based systems. The review discusses the biological factors that make T. pallidum difficult to cultivate, including genome reduction, limited metabolic capacity, dependence on host cells and oxygen sensitivity. Long-term co-cultivation with rabbit epithelial Sf1Ep cells in TpCM-2 medium is considered a key technological stage in experimental treponemology. It is concluded that in vitro cultivation of T. pallidum should be regarded as a promising scientific and technological platform for studying pathogen physiology, host-cell interactions, antimicrobial susceptibility, reduction of dependence on animal models and development of biosafe experimental approaches.

Treponema pallidumсифилискультивирование in vitroSf1EpTpCM-2человеческие фибробластыклеточные культурыкроличья модельбиобезопасностьтрепонемологияTreponema pallidumsyphilisin vitro cultivationSf1EpTpCM-2human fibroblastscell culturesrabbit modelbiosafetytreponemologyReferencesWorld Health Organization. Sexually transmitted infections (STIs): strategic information. Syphilis estimates, 2022 / World Health Organization. - Geneva : WHO, 2024.World Health Organization. Sexually transmitted infections (STIs): strategic information. Syphilis estimates, 2022 / World Health Organization. - Geneva : WHO, 2024.Chlamydia, gonorrhoea, trichomoniasis and syphilis: global prevalence and incidence estimates, 2016 / J. Rowley, S. Vander Hoorn, E. Korenromp [et al.] // Bulletin of the World Health Organization. - 2019. - Vol. 97, No. 8. - P. 548-562P. - DOI: 10.2471/BLT.18.228486.Chlamydia, gonorrhoea, trichomoniasis and syphilis: global prevalence and incidence estimates, 2016 / J. Rowley, S. Vander Hoorn, E. Korenromp [et al.] // Bulletin of the World Health Organization. - 2019. - Vol. 97, No. 8. - P. 548-562P. - DOI: 10.2471/BLT.18.228486.Peeling R.W. Syphilis / R.W. Peeling, D. Mabey, M.L. Kamb, X.S. Chen, J.D. Radolf, A.S. Benzaken // Nature Reviews Disease Primers. - 2017. - Vol. 3. - Article 17073. - DOI: 10.1038/nrdp.2017.73.Peeling R.W. Syphilis / R.W. Peeling, D. Mabey, M.L. Kamb, X.S. Chen, J.D. Radolf, A.S. Benzaken // Nature Reviews Disease Primers. - 2017. - Vol. 3. - Article 17073. - DOI: 10.1038/nrdp.2017.73.Centers for Disease Control and Prevention. Sexually Transmitted Infections Surveillance, 2023 / Centers for Disease Control and Prevention. - Atlanta : CDC, 2024.Centers for Disease Control and Prevention. Sexually Transmitted Infections Surveillance, 2023 / Centers for Disease Control and Prevention. - Atlanta : CDC, 2024.Sexually transmitted infections: challenges ahead / M. Unemo, C.S. Bradshaw, J.S. Hocking [et al.] // The Lancet Infectious Diseases. - 2017. - Vol. 17, No. 8. - P. e235-e279.Sexually transmitted infections: challenges ahead / M. Unemo, C.S. Bradshaw, J.S. Hocking [et al.] // The Lancet Infectious Diseases. - 2017. - Vol. 17, No. 8. - P. e235-e279.CDC Laboratory Recommendations for Syphilis Testing, United States, 2024 / J.R. Papp, I.U. Park, Y. Fakile [et al.] // MMWR Recommendations and Reports. - 2024. - Vol. 73, No. 1. - P. 1-32. - DOI: 10.15585/mmwr.rr7301a1.CDC Laboratory Recommendations for Syphilis Testing, United States, 2024 / J.R. Papp, I.U. Park, Y. Fakile [et al.] // MMWR Recommendations and Reports. - 2024. - Vol. 73, No. 1. - P. 1-32. - DOI: 10.15585/mmwr.rr7301a1.Complete genome sequence of Treponema pallidum, the syphilis spirochete / C.M. Fraser, S.J. Norris, G.M. Weinstock [et al.] // Science. - 1998. - Vol. 281, No. 5375. - P. 375-388. - DOI: 10.1126/science.281.5375.375.Complete genome sequence of Treponema pallidum, the syphilis spirochete / C.M. Fraser, S.J. Norris, G.M. Weinstock [et al.] // Science. - 1998. - Vol. 281, No. 5375. - P. 375-388. - DOI: 10.1126/science.281.5375.375.Weinstock G.M. The genome of Treponema pallidum: new light on the agent of syphilis / G.M. Weinstock, J.M. Hardham, M.P. McLeod, E.J. Sodergren, S.J. Norris // FEMS Microbiology Reviews. - 1998. - Vol. 22, No. 4. - P. 323-332.Weinstock G.M. The genome of Treponema pallidum: new light on the agent of syphilis / G.M. Weinstock, J.M. Hardham, M.P. McLeod, E.J. Sodergren, S.J. Norris // FEMS Microbiology Reviews. - 1998. - Vol. 22, No. 4. - P. 323-332.Norris S.J. Biology of Treponema pallidum: correlation of functional activities with genome sequence data / S.J. Norris, D.L. Cox, G.M. Weinstock // Journal of Molecular Microbiology and Biotechnology. - 2001. - Vol. 3, No. 1. - P. 37-62.Norris S.J. Biology of Treponema pallidum: correlation of functional activities with genome sequence data / S.J. Norris, D.L. Cox, G.M. Weinstock // Journal of Molecular Microbiology and Biotechnology. - 2001. - Vol. 3, No. 1. - P. 37-62.Lafond R.E. Biological basis for syphilis / R.E. Lafond, S.A. Lukehart // Clinical Microbiology Reviews. - 2006. - Vol. 19, No. 1. - P. 29-49. - DOI: 10.1128/CMR.19.1.29-49.2006.Lafond R.E. Biological basis for syphilis / R.E. Lafond, S.A. Lukehart // Clinical Microbiology Reviews. - 2006. - Vol. 19, No. 1. - P. 29-49. - DOI: 10.1128/CMR.19.1.29-49.2006.Treponema pallidum, the syphilis spirochete: making a living as a stealth pathogen / J.D. Radolf, R.K. Deka, A. Anand [et al.] // Nature Reviews Microbiology. - 2016. - Vol. 14, No. 12. - P. 744-759. - DOI: 10.1038/nrmicro.2016.141.Treponema pallidum, the syphilis spirochete: making a living as a stealth pathogen / J.D. Radolf, R.K. Deka, A. Anand [et al.] // Nature Reviews Microbiology. - 2016. - Vol. 14, No. 12. - P. 744-759. - DOI: 10.1038/nrmicro.2016.141.Radolf J.D. The Treponema pallidum outer membrane / J.D. Radolf, S. Kumar // Current Topics in Microbiology and Immunology. - 2018. - Vol. 415. - P. 1-38. - DOI: 10.1007/82_2017_44.Radolf J.D. The Treponema pallidum outer membrane / J.D. Radolf, S. Kumar // Current Topics in Microbiology and Immunology. - 2018. - Vol. 415. - P. 1-38. - DOI: 10.1007/82_2017_44.Structural modeling of the Treponema pallidum outer membrane protein repertoire / K.L. Hawley, J.M. Montezuma-Rusca, K.N. Delgado [et al.] // Journal of Bacteriology. - 2021. - Vol. 203, No. 15. - Article e00082-21.Structural modeling of the Treponema pallidum outer membrane protein repertoire / K.L. Hawley, J.M. Montezuma-Rusca, K.N. Delgado [et al.] // Journal of Bacteriology. - 2021. - Vol. 203, No. 15. - Article e00082-21.Treponema pallidum major sheath protein homologue TprK is a target of opsonic antibody and the protective immune response / A. Centurion-Lara, C. Castro, L. Barrett [et al.] // Journal of Experimental Medicine. - 1999. - Vol. 189, No. 4. - P. 647-656.Treponema pallidum major sheath protein homologue TprK is a target of opsonic antibody and the protective immune response / A. Centurion-Lara, C. Castro, L. Barrett [et al.] // Journal of Experimental Medicine. - 1999. - Vol. 189, No. 4. - P. 647-656.Antigenic variation in Treponema pallidum: TprK sequence diversity accumulates in response to immune pressure during experimental syphilis / L. Giacani, B.J. Molini, E.Y. Kim [et al.] // Journal of Immunology. - 2010. - Vol. 184, No. 7. - P. 3822-3829.Antigenic variation in Treponema pallidum: TprK sequence diversity accumulates in response to immune pressure during experimental syphilis / L. Giacani, B.J. Molini, E.Y. Kim [et al.] // Journal of Immunology. - 2010. - Vol. 184, No. 7. - P. 3822-3829.Lukehart S.A. Isolation and laboratory maintenance of Treponema pallidum / S.A. Lukehart, C.M. Marra // Current Protocols in Microbiology. - 2007. - Chapter 12. - Unit 12A.1. - DOI: 10.1002/9780471729259.mc12a01s7.Lukehart S.A. Isolation and laboratory maintenance of Treponema pallidum / S.A. Lukehart, C.M. Marra // Current Protocols in Microbiology. - 2007. - Chapter 12. - Unit 12A.1. - DOI: 10.1002/9780471729259.mc12a01s7.National Research Council. Guide for the Care and Use of Laboratory Animals / National Research Council. - 8th ed. - Washington, DC : The National Academies Press, 2011. - DOI: 10.17226/12910.National Research Council. Guide for the Care and Use of Laboratory Animals / National Research Council. - 8th ed. - Washington, DC : The National Academies Press, 2011. - DOI: 10.17226/12910.Fieldsteel A.H. Cultivation of virulent Treponema pallidum in tissue culture / A.H. Fieldsteel, D.L. Cox, R.A. Moeckli // Infection and Immunity. - 1981. - Vol. 32, No. 2. - P. 908-915. - DOI: 10.1128/iai.32.2.908-915.1981.Fieldsteel A.H. Cultivation of virulent Treponema pallidum in tissue culture / A.H. Fieldsteel, D.L. Cox, R.A. Moeckli // Infection and Immunity. - 1981. - Vol. 32, No. 2. - P. 908-915. - DOI: 10.1128/iai.32.2.908-915.1981.Fieldsteel A.H. Prolonged survival of virulent Treponema pallidum (Nichols strain) in cellfree and tissue culture systems / A.H. Fieldsteel, F.A. Becker, J.G. Stout // Infection and Immunity. - 1977. - Vol. 18, No. 1. - P. 173-182. - DOI: 10.1128/iai.18.1.173-182.1977.Fieldsteel A.H. Prolonged survival of virulent Treponema pallidum (Nichols strain) in cellfree and tissue culture systems / A.H. Fieldsteel, F.A. Becker, J.G. Stout // Infection and Immunity. - 1977. - Vol. 18, No. 1. - P. 173-182. - DOI: 10.1128/iai.18.1.173-182.1977.Fitzgerald T.J. Treponema pallidum (Nichols strain) in tissue cultures: cellular attachment, entry, and survival / T.J. Fitzgerald, J.N. Miller, J.A. Sykes // Infection and Immunity. - 1975. - Vol. 11, No. 5. - P. 1133-1140. - DOI: 10.1128/iai.11.5.1133-1140.1975.Fitzgerald T.J. Treponema pallidum (Nichols strain) in tissue cultures: cellular attachment, entry, and survival / T.J. Fitzgerald, J.N. Miller, J.A. Sykes // Infection and Immunity. - 1975. - Vol. 11, No. 5. - P. 1133-1140. - DOI: 10.1128/iai.11.5.1133-1140.1975.Interaction of Treponema pallidum (Nichols strain) with cultured mammalian cells: effects of oxygen, reducing agents, serum supplements, and different cell types / T.J. Fitzgerald, R.C. Johnson, J.A. Sykes, J.N. Miller // Infection and Immunity. - 1977. - Vol. 15, No. 2. - P. 444-452. - DOI: 10.1128/iai.15.2.444-452.1977.Interaction of Treponema pallidum (Nichols strain) with cultured mammalian cells: effects of oxygen, reducing agents, serum supplements, and different cell types / T.J. Fitzgerald, R.C. Johnson, J.A. Sykes, J.N. Miller // Infection and Immunity. - 1977. - Vol. 15, No. 2. - P. 444-452. - DOI: 10.1128/iai.15.2.444-452.1977.Growth and subculture of pathogenic Treponema pallidum (Nichols strain) in BHK-21 cultured tissue cells / R.H. Jones, M.A. Finn, J.J. Thomas, C. Folger // British Journal of Venereal Diseases. - 1976. - Vol. 52, No. 1. - P. 18-23. - DOI: 10.1136/sti.52.1.18.Growth and subculture of pathogenic Treponema pallidum (Nichols strain) in BHK-21 cultured tissue cells / R.H. Jones, M.A. Finn, J.J. Thomas, C. Folger // British Journal of Venereal Diseases. - 1976. - Vol. 52, No. 1. - P. 18-23. - DOI: 10.1136/sti.52.1.18.Foster J.W. The in vitro cultivation of Treponema pallidum. Corroborative studies / J.W. Foster, D.S. Kellogg, J.W. Clark, A. Balows // British Journal of Venereal Diseases. - 1977. - Vol. 53, No. 6. - P. 338-339. - DOI: 10.1136/sti.53.6.338.Foster J.W. The in vitro cultivation of Treponema pallidum. Corroborative studies / J.W. Foster, D.S. Kellogg, J.W. Clark, A. Balows // British Journal of Venereal Diseases. - 1977. - Vol. 53, No. 6. - P. 338-339. - DOI: 10.1136/sti.53.6.338.Fieldsteel A.H. Further studies on replication of virulent Treponema pallidum in tissue cultures of Sf1Ep cells / A.H. Fieldsteel, D.L. Cox, R.A. Moeckli // Infection and Immunity. - 1982. - Vol. 35, No. 2. - P. 449-455.Fieldsteel A.H. Further studies on replication of virulent Treponema pallidum in tissue cultures of Sf1Ep cells / A.H. Fieldsteel, D.L. Cox, R.A. Moeckli // Infection and Immunity. - 1982. - Vol. 35, No. 2. - P. 449-455.Norris S.J. Factors affecting the multiplication and subculture of Treponema pallidum subsp. pallidum in a tissue culture system / S.J. Norris, D.G. Edmondson // Infection and Immunity. - 1986. - Vol. 53, No. 3. - P. 534-539.Norris S.J. Factors affecting the multiplication and subculture of Treponema pallidum subsp. pallidum in a tissue culture system / S.J. Norris, D.G. Edmondson // Infection and Immunity. - 1986. - Vol. 53, No. 3. - P. 534-539.Edmondson D.G. Long-term in vitro culture of the syphilis spirochete Treponema pallidum subsp. pallidum / D.G. Edmondson, B. Hu, S.J. Norris // mBio. - 2018. - Vol. 9, No. 3. - Article e01153-18. - DOI: 10.1128/mBio.01153-18.Edmondson D.G. Long-term in vitro culture of the syphilis spirochete Treponema pallidum subsp. pallidum / D.G. Edmondson, B. Hu, S.J. Norris // mBio. - 2018. - Vol. 9, No. 3. - Article e01153-18. - DOI: 10.1128/mBio.01153-18.Parameters affecting continuous in vitro culture of Treponema pallidum strains / D.G. Edmondson, B.D. DeLay, L.E. Kowis, S.J. Norris // mBio. - 2021. - Vol. 12, No. 1. - Article e03536- 20. - DOI: 10.1128/mBio.03536-20.Parameters affecting continuous in vitro culture of Treponema pallidum strains / D.G. Edmondson, B.D. DeLay, L.E. Kowis, S.J. Norris // mBio. - 2021. - Vol. 12, No. 1. - Article e03536- 20. - DOI: 10.1128/mBio.03536-20.Edmondson D.G. In vitro cultivation of the syphilis spirochete Treponema pallidum / D.G. Edmondson, S.J. Norris // Current Protocols. - 2021. - Vol. 1. - Article e44. - DOI: 10.1002/cpz1.44.Edmondson D.G. In vitro cultivation of the syphilis spirochete Treponema pallidum / D.G. Edmondson, S.J. Norris // Current Protocols. - 2021. - Vol. 1. - Article e44. - DOI: 10.1002/cpz1.44.In vitro analysis of seven syphilis-causing Treponema pallidum strains revealed inherent growth rate differences / J. Bosak, M. Hrala, P. Andrla [et al.] // Scientific Reports. - 2025. - Vol. 15. - Article 18827. - DOI: 10.1038/s41598-025-18827-9.In vitro analysis of seven syphilis-causing Treponema pallidum strains revealed inherent growth rate differences / J. Bosak, M. Hrala, P. Andrla [et al.] // Scientific Reports. - 2025. - Vol. 15. - Article 18827. - DOI: 10.1038/s41598-025-18827-9.In vitro isolation of contemporary Treponema pallidum strains directly from clinical samples of syphilis patients / J. Bosak, M. Hrala, F. Skokan [et al.] // Clinical Microbiology and Infection. - 2025. - Vol. 31, No. 6. - P. 1061-1065. - DOI: 10.1016/j.cmi.2025.03.017.In vitro isolation of contemporary Treponema pallidum strains directly from clinical samples of syphilis patients / J. Bosak, M. Hrala, F. Skokan [et al.] // Clinical Microbiology and Infection. - 2025. - Vol. 31, No. 6. - P. 1061-1065. - DOI: 10.1016/j.cmi.2025.03.017.Directly sequenced genomes of contemporary strains of syphilis reveal recombination-driven diversity in genes encoding predicted surface-exposed antigens / L. Grillova, T. Bawa, L. Mikalova [et al.] // Frontiers in Microbiology. - 2019. - Vol. 10. - Article 1691. - DOI: 10.3389/fmicb.2019.01691.Directly sequenced genomes of contemporary strains of syphilis reveal recombination-driven diversity in genes encoding predicted surface-exposed antigens / L. Grillova, T. Bawa, L. Mikalova [et al.] // Frontiers in Microbiology. - 2019. - Vol. 10. - Article 1691. - DOI: 10.3389/fmicb.2019.01691.Global phylogeny of Treponema pallidum lineages reveals recent expansion and spread of contemporary syphilis / M.A. Beale, M. Marks, M.J. Cole [et al.] // Nature Microbiology. - 2021. - Vol. 6, No. 12. - P. 1549-1560. - DOI: 10.1038/s41564-021-01000-z.Global phylogeny of Treponema pallidum lineages reveals recent expansion and spread of contemporary syphilis / M.A. Beale, M. Marks, M.J. Cole [et al.] // Nature Microbiology. - 2021. - Vol. 6, No. 12. - P. 1549-1560. - DOI: 10.1038/s41564-021-01000-z.Enhanced molecular typing of Treponema pallidum: geographical distribution of strain types and association with neurosyphilis / C.M. Marra, S.K. Sahi, L.C. Tantalo [et al.] // Journal of Infectious Diseases. - 2010. - Vol. 202, No. 9. - P. 1380-1388.Enhanced molecular typing of Treponema pallidum: geographical distribution of strain types and association with neurosyphilis / C.M. Marra, S.K. Sahi, L.C. Tantalo [et al.] // Journal of Infectious Diseases. - 2010. - Vol. 202, No. 9. - P. 1380-1388.Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster / N. Arora, V.J. Schuenemann, G. Jager [et al.] // Nature Microbiology. - 2016. - Vol. 2. - Article 16245. - DOI: 10.1038/nmicrobiol.2016.245.Origin of modern syphilis and emergence of a pandemic Treponema pallidum cluster / N. Arora, V.J. Schuenemann, G. Jager [et al.] // Nature Microbiology. - 2016. - Vol. 2. - Article 16245. - DOI: 10.1038/nmicrobiol.2016.245.Genomic epidemiology of syphilis reveals independent emergence of macrolide resistance across multiple circulating lineages / M.A. Beale, M. Marks, S.K. Sahi [et al.] // Nature Communications. - 2019. - Vol. 10. - Article 3255. - DOI: 10.1038/s41467-019-11216-7.Genomic epidemiology of syphilis reveals independent emergence of macrolide resistance across multiple circulating lineages / M.A. Beale, M. Marks, S.K. Sahi [et al.] // Nature Communications. - 2019. - Vol. 10. - Article 3255. - DOI: 10.1038/s41467-019-11216-7.Characterisation of Treponema pallidum lineages within the contemporary syphilis outbreak in Australia: a genomic epidemiological analysis / M.L. Taouk, G. Taiaroa, S. Pasricha [et al.] // The Lancet Microbe. - 2022. - Vol. 3, No. 6. - P. e417-e426. - DOI: 10.1016/S2666-5247(22)00035-0.Characterisation of Treponema pallidum lineages within the contemporary syphilis outbreak in Australia: a genomic epidemiological analysis / M.L. Taouk, G. Taiaroa, S. Pasricha [et al.] // The Lancet Microbe. - 2022. - Vol. 3, No. 6. - P. e417-e426. - DOI: 10.1016/S2666-5247(22)00035-0.Clinical and genomic diversity of Treponema pallidum subspecies pallidum to inform vaccine research: an international, molecular epidemiology study / A.C. Sena, M.M. Matoga, L. Yang [et al.] // The Lancet Microbe. - 2024. - Vol. 5, No. 9. - Article 100871. - DOI: 10.1016/S2666-5247(24)00087-9.Clinical and genomic diversity of Treponema pallidum subspecies pallidum to inform vaccine research: an international, molecular epidemiology study / A.C. Sena, M.M. Matoga, L. Yang [et al.] // The Lancet Microbe. - 2024. - Vol. 5, No. 9. - Article 100871. - DOI: 10.1016/S2666-5247(24)00087-9Insights into Treponema pallidum genomics from modern and ancient genomes using a novel mapping strategy / M. Pla-Diaz, G. Akgul, M. Molak [et al.] // BMC Biology. - 2025. - Vol. 23, No. 1. - Article 7. - DOI: 10.1186/s12915-024-02108-4.Insights into Treponema pallidum genomics from modern and ancient genomes using a novel mapping strategy / M. Pla-Diaz, G. Akgul, M. Molak [et al.] // BMC Biology. - 2025. - Vol. 23, No. 1. - Article 7. - DOI: 10.1186/s12915-024-02108-4.Integrated genomic approaches improve Treponema pallidum phylogenetics and lineage classification / G.S. Long, A.E. Singh [et al.] // Canadian Journal of Microbiology. - 2025. - Vol. 71. - P. 1-11. - DOI: 10.1139/cjm-2025-0021.Integrated genomic approaches improve Treponema pallidum phylogenetics and lineage classification / G.S. Long, A.E. Singh [et al.] // Canadian Journal of Microbiology. - 2025. - Vol. 71. - P. 1-11. - DOI: 10.1139/cjm-2025-0021.First human cell-based cultivation system for the syphilis spirochete Treponema pallidum / J. Bosak, M. Hrala, P. Pospisilova [et al.] // BMC Microbiology. - 2026. - Vol. 26. - Article 288. - DOI: 10.1186/s12866-026-04856-5.First human cell-based cultivation system for the syphilis spirochete Treponema pallidum / J. Bosak, M. Hrala, P. Pospisilova [et al.] // BMC Microbiology. - 2026. - Vol. 26. - Article 288. - DOI: 10.1186/s12866-026-04856-5.Applications and research trends in organoid-based infectious disease models / J.O. Ryu, Y.J. Seong, E. Lee [et al.] // Scientific Reports. - 2025. - Vol. 15. - Article 25185. - DOI: 10.1038/s41598-025-07816-7.Applications and research trends in organoid-based infectious disease models / J.O. Ryu, Y.J. Seong, E. Lee [et al.] // Scientific Reports. - 2025. - Vol. 15. - Article 25185. - DOI: 10.1038/s41598-025-07816-7.Mapping the scientific output of organoids for animal and human modeling infectious diseases: a bibliometric assessment / J. Yan, A. Wiedemann [et al.] // Veterinary Research. - 2024. - Vol. 55. - Article 81. - DOI: 10.1186/s13567-024-01333-7.Mapping the scientific output of organoids for animal and human modeling infectious diseases: a bibliometric assessment / J. Yan, A. Wiedemann [et al.] // Veterinary Research. - 2024. - Vol. 55. - Article 81. - DOI: 10.1186/s13567-024-01333-7.Park G. Replacing animal testing with stem cell-organoids: advantages and limitations / G. Park, Y.A. Rim, Y. Sohn, Y. Nam, J.H. Ju // Stem Cell Reviews and Reports. - 2024. - Vol. 20, No. 6. - P. 1375-1386. - DOI: 10.1007/s12015-024-10723-5.Park G. Replacing animal testing with stem cell-organoids: advantages and limitations / G. Park, Y.A. Rim, Y. Sohn, Y. Nam, J.H. Ju // Stem Cell Reviews and Reports. - 2024. - Vol. 20, No. 6. - P. 1375-1386. - DOI: 10.1007/s12015-024-10723-5.3D engineered tissue models for studying human-specific infectious viral diseases / K.S. Hwang, J. Choi, J. Kim [et al.] // Bioactive Materials. - 2023. - Vol. 21. - P. 576-594. - DOI: 10.1016/j.bioactmat.2022.09.014.3D engineered tissue models for studying human-specific infectious viral diseases / K.S. Hwang, J. Choi, J. Kim [et al.] // Bioactive Materials. - 2023. - Vol. 21. - P. 576-594. - DOI: 10.1016/j.bioactmat.2022.09.014.World Health Organization. Laboratory Biosafety Manual / World Health Organization. - 4th ed. - Geneva : WHO, 2020. - ISBN 978-92-4-001131-1.World Health Organization. Laboratory Biosafety Manual / World Health Organization. - 4th ed. - Geneva : WHO, 2020. - ISBN 978-92-4-001131-1.World Health Organization. Laboratory Biosafety Manual: Risk Assessment / World Health Organization. - Geneva : WHO, 2020.World Health Organization. Laboratory Biosafety Manual: Risk Assessment / World Health Organization. - Geneva : WHO, 2020.Public Health Agency of Canada. Pathogen Safety Data Sheet: Treponema pallidum / Public Health Agency of Canada. - Updated September 27, 2024.Public Health Agency of Canada. Pathogen Safety Data Sheet: Treponema pallidum / Public Health Agency of Canada. - Updated September 27, 2024.Stamm L.V. Syphilis: antibiotic treatment and resistance / L.V. Stamm // Epidemiology and Infection. - 2015. - Vol. 143, No. 8. - P. 1567-1574. - DOI: 10.1017/S0950268814002830.Stamm L.V. Syphilis: antibiotic treatment and resistance / L.V. Stamm // Epidemiology and Infection. - 2015. - Vol. 143, No. 8. - P. 1567-1574. - DOI: 10.1017/S0950268814002830.Near-universal resistance to macrolides of Treponema pallidum in North America / N.A.P. Lieberman, T.B. Reid, C.A. Cannon [et al.] // New England Journal of Medicine. - 2024. - Vol. 390, No. 22. - P. 2127-2128. - DOI: 10.1056/NEJMc2314441.Near-universal resistance to macrolides of Treponema pallidum in North America / N.A.P. Lieberman, T.B. Reid, C.A. Cannon [et al.] // New England Journal of Medicine. - 2024. - Vol. 390, No. 22. - P. 2127-2128. - DOI: 10.1056/NEJMc2314441.Treponema pallidum macrolide resistance and molecular strain types in South Africa / J.M.E. Venter, E.E. Muller, M.P. Mahlangu [et al.] // Journal of Clinical Microbiology. - 2021. - Vol. 59. - Article e02385-20.Treponema pallidum macrolide resistance and molecular strain types in South Africa / J.M.E. Venter, E.E. Muller, M.P. Mahlangu [et al.] // Journal of Clinical Microbiology. - 2021. - Vol. 59. - Article e02385-20.Muller E.E. Macrolide resistance testing and molecular subtyping of Treponema pallidum strains from southern Africa / E.E. Muller, G. Paz-Bailey, D.A. Lewis // Sexually Transmitted Infections. - 2012. - Vol. 88, No. 6. - P. 470-474. - DOI: 10.1136/sextrans-2011-050322.Muller E.E. Macrolide resistance testing and molecular subtyping of Treponema pallidum strains from southern Africa / E.E. Muller, G. Paz-Bailey, D.A. Lewis // Sexually Transmitted Infections. - 2012. - Vol. 88, No. 6. - P. 470-474. - DOI: 10.1136/sextrans-2011-050322.Сейдахметова Б.А., Жаппарова Г.А., Мараховская Л.Г., Теребай А.А., Наханов А.К. Масштабирование культуры клеток Vero для производства биопрепаратов // Биобезопасность и Биотехнология. - 2022. - № 9. - С. 44-52. - DOI: 10.58318/2957-5702-2022-9-44-52.Seidakhmetova B.A., Zhapparova G.A., Marakhovskaya L.G., Terebai A.A., Nakhanov A.K. Masshtabirovanie kul'tury kletok Vero dlya proizvodstva biopreparatov [Scaling up Vero cell culture for the production of biological products]. Biobezopasnost' i Biotekhnologiya (Biosafety and Biotechnology). 2022;(9):44–52. doi: 10.58318/2957-5702-2022-9-44-52.Бурабаев Б.К., Джекебеков К.К., Уланкызы А. [и др.]. Управление биологическими рисками в Научно-исследовательском институте проблем биологической безопасности // Биобезопасность и Биотехнология. - 2020. - № 1. - С. 10-11.Burabaev B.K., Dzhekebekov K.K., Ulankyzy A., et al. Upravlenie biologicheskimi riskami v Nauchno-issledovatel'skom institute problem biologicheskoi bezopasnosti [Biological risk management at the Research Institute for Biological Safety Problems]. Biobezopasnost' i Biotekhnologiya (Biosafety and Biotechnology). 2020;(1):10–11.Килибаев С.С., Таболдиев Д.Р., Джалдыбаева А.Е., Жунискулов Р.Б. Система биологической безопасности и биозащиты в НИИ // Биобезопасность и Биотехнология. - 2023. - № 14.Kilibaev S.S., Taboldiev D.R., Dzhaldybaeva A.E., Zhuniskulov R.B. Sistema biologicheskoi bezopasnosti i biozashchity v NII [Biosafety and biosecurity system in the research institute]. Biobezopasnost' i Biotekhnologiya (Biosafety and Biotechnology). 2023;(14).Canadian Public Health Laboratory Network National Syphilis In-Laboratory Serological Testing Recommendations / M. Morshed [et al.] // Journal of the Association of Medical Microbiology and Infectious Disease Canada. - 2025. - DOI: 10.3138/jammi-2024-0027.Canadian Public Health Laboratory Network National Syphilis In-Laboratory Serological Testing Recommendations / M. Morshed [et al.] // Journal of the Association of Medical Microbiology and Infectious Disease Canada. - 2025. - DOI: 10.3138/jammi-2024-0027.Giacani L. The endemic treponematoses / L. Giacani, S.A. Lukehart // Clinical Microbiology Reviews. - 2014. - Vol. 27, No. 1. - P. 89-115. - DOI: 10.1128/CMR.00070-13.Giacani L. The endemic treponematoses / L. Giacani, S.A. Lukehart // Clinical Microbiology Reviews. - 2014. - Vol. 27, No. 1. - P. 89-115. - DOI: 10.1128/CMR.00070-13.Smajs D. Genetics of human and animal uncultivable treponemal pathogens / D. Smajs, M. Strouhal, S. Knauf // Infection, Genetics and Evolution. - 2018. - Vol. 61. - P. 92-107.Smajs D. Genetics of human and animal uncultivable treponemal pathogens / D. Smajs, M. Strouhal, S. Knauf // Infection, Genetics and Evolution. - 2018. - Vol. 61. - P. 92-107.A defined syphilis vaccine candidate inhibits dissemination of Treponema pallidum subspecies pallidum / K.V. Lithgow, R. Hof, C. Wetherell [et al.] // Nature Communications. - 2017. - Vol. 8. - Article 14273.A defined syphilis vaccine candidate inhibits dissemination of Treponema pallidum subspecies pallidum / K.V. Lithgow, R. Hof, C. Wetherell [et al.] // Nature Communications. - 2017. - Vol. 8. - Article 14273.

The authors declare that there are no conflicts of interest present.