ssmuБюллетень сибирской медициныBulletin of Siberian Medicine1682-03631819-3684Siberian State Medical University, the Ministry of Healthcare of the Russian Federation10.20538/1682-0363-2018-1-36-44ssmu-1113Research ArticleОРИГИНАЛЬНЫЕ СТАТЬИORIGINAL PAPERSУФО-индуцированная экспрессия эндогенного ретровируса человека HERV-E λ 4-1 в мононуклеарных клетках кровиUVI-induced endogenous retrovirus HERV-E λ 4-1 expression in blood mononuclear cellsГольдинаИ. А.GoldinaI. A.

Гольдина Ирина Александровна, науч. сотрудник, лаборатория регуляции иммунопоэза.

630099, г. Новосибирск, ул. Ядринцевская, 14. 

Goldina Irina A., Researcher, Regulation Immunopoiesis Laboratory.

14, Yadrincevskaya Str., Novosibirsk, 630099.

igoldina@mail.ruГайдульК. В.GaidulK. V.

Гайдуль Константин Валентинович, д-р мед. наук, профессор, руководитель лаборатории регуляции иммунопоэза.

630099, г. Новосибирск, ул. Ядринцевская, 14. 

Gaidul Konstantin V., DM, Professor, Head of the Regulation Immunopoiesis Laboratory.

14, Yadrincevskaya Str., Novosibirsk, 630099.

КозловВ. А.KozlovV. A.

Козлов Владимир Александрович, академик РАН, д-р мед. наук, профессор, науч. руководитель. 

630099, г. Новосибирск, ул. Ядринцевская, 14. 

Kozlov Vladimir А., DM, Professor, Academician of RAS, Scientific Head. 

14, Yadrincevskaya Str., Novosibirsk, 630099.

Научно-исследовательский институт фундаментальной и клинической иммунологии (НИИФиКИ).РоссияScientific Research Institute of Fundamental and Clinical Immunology (SRIFCI).Russian Federation2018300320181713644Copyright © Гольдина И.А., Гайдуль К.В., Козлов В.А., 20182018Гольдина И.А., Гайдуль К.В., Козлов В.А.Goldina I.A., Gaidul K.V., Kozlov V.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://bulletin.ssmu.ru/jour/article/view/1113

Влияние различных факторов внешней среды опосредованно, через эпигенетические механизмы регуляции экспрессии генов, способно приводить к активации эндогенных ретровирусов (ЭР) человека.

Целью настоящего исследования явилось изучение возможности активации эндогенного ретровируса человека I класса HERV-E λ 4-1 (ЭР λ 4-1) в мононуклеарных клетках крови (МНК) здоровых лиц в результате воздействия УФО-излучения in vitro.

Материалы и методы

Материалы и методы. Суспензию индивидуальных образцов МНК доноров (20 х 106/мл) в среде RPMI-1640 подвергали УФО-облучению в течение 5 мин на УФО-излучателе при длине волны 340 нм и интенсивности излучения 50 Вт/м2. После облучения образцы клеток культивировали в течение 24 ч в полной культуральной среде в СО2-инкубаторе при 37 °С. Перед облучением, а также после него в образцах МНК определяли пролиферативную активность на основании включения меченного тритием тимидина, жизнеспособность, методом окраски трипановым синим, и экспрессию ЭР E λ 4-1 методом обратно-транскриптазной полимеразной цепной реакции.

Основные результаты

Основные результаты. УФО-облучение культур мононуклеарных клеток крови в течение 5 мин не приводило к изменению их жизнеспособности и функциональной активности. Исследование частоты случаев экспрессии гена env ЭР λ 4-1 в образцах МНК крови доноров до и после воздействия УФОизлучения выявило различия данного показателя. Так, до воздействия УФО-излучения количество случаев экспрессии env ЭР λ 4-1 составило 6,16% (4/65 человек), тогда как после облучения его экспрессия определялась значительно чаще – в 24,62% случаев (16/65 человек), p < 0,05. Наряду с увеличением частоты экспрессии наблюдалось и повышение уровня мРНК гена env ЭР λ 4-1 с 87 (44; 120) усл. ед. опт. плотности до 264 (135; 306) усл. ед. опт. плотности, p < 0,05.

Заключение

Заключение. Воздействие УФО-излучения с интенсивностью 50 Вт/м2 в течение 5 мин на мононуклеарные клетки крови условно-здоровых лиц in vitro приводит к активации эндогенного ретровируса человека HERV-E λ 4-1: увеличению количества случаев его экспрессии и повышению уровня мРНК. 

The influence of various environmental factors indirectly, through the epigenetic mechanisms of regulation of gene expression, can lead to the activation of human endogenous retroviruses. The purpose of this study was to investigate the possibility of activation of the first class HERV-E λ 4-1 (ER λ 4-1) endogenous retrovirus as a result of exposure to UV radiation in vitro.

Materials and methods

Materials and methods. Blood mononuclear cells (MNCs) of conditionally healthy individuals in a concentration of 20 x 106/ml were exposed to UV irradiation for 5 minutes on an ultraviolet radiator at a wavelength of 340 nm and a radiation intensity of 50 W/m2 in vitro. After irradiation, the cell samples were cultured for 24 hours in a complete culture medium in a CO2 incubator. Then, in these cell culture samples the proliferative activity, based on the incorporation of tritium labeled thymidine, a viability, by the trypan blue staining, and ER-E λ 4-1 expression by the reverse transcriptase polymerase chain reaction method, were determined.

The main results

The main results. UV irradiation of mononuclear cell cultures for 5 minutes did not leads to the changes in their viability and functional activity. The study of the of the env ER λ 4-1 gene expression frequency in the MNC of donor’s blood before and after the exposure to UV radiation revealed the differences in this index. Thus, before the exposure to UV radiation, the expression rate of env ER-λ 4-1 was 4.4% (2/45), whereas after the irradiation its expression was determined much more often  24% (11/45). Along with an increase in the expression frequency, an augmentation in the mRNA level of the env gene ER-λ 4-1  was also observed.

Conclusion

Conclusion. Thus, the exposure to ultraviolet radiation with the intensity of 50 W/m2 for 5 minutes on blood mononuclear cells of conditionally healthy individuals in vitro leads to activation of the human endogenous retrovirus HERV-E λ 4-1: an increase of its expression frequency and the level of mRNA. 

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