PT - JOURNAL ARTICLE AU - Tatiana P. Ospelnikova AU - D. S. Levitskaya AU - L.V. Kolodyazhnaya AU - A. D. Shitova AU - V. N. Osiptsov AU - Nadejda O. Kryukova AU - Dmitrii V. Pakhomov AU - Ekaterina A. Khromova AU - Lidia Arifullina AU - Irina A. Baranova AU - Aleksandr G. Chuchalin AU - Mikhail P. Kostinov AU - Oxana A. Svitich TI - The biological activity of interferons in post-COVID syndrome AID - 10.1183/23120541.LSC-2022.240 DP - 2022 Mar 10 TA - ERJ Open Research PG - 240 VI - 8 IP - suppl 8 4099 - http://openres.ersjournals.com/content/8/suppl_8/240.short 4100 - http://openres.ersjournals.com/content/8/suppl_8/240.full SO - erjor2022 Mar 10; 8 AB - The immunopathogenesis of COVID-19 is associated with the development of unbalanced immune response to SARS-CoV-2 virus with insufficient synthesis of interferon (IFN) at the onset of disease and subsequent overproduction of proinflammatory cytokines.Objective: assessment of biologically active (ba) IFNs in patients with the post-COVID syndrome in period of rehabilitation.Materials and methods: Biomaterial of whole blood from 47 patients in postcovid period. The studies were carried out according to the methodology developed by the authors for assessing ba of IFN (IFN status) in cells-virus test. The laboratory research was funded by a grant from the Russian Foundation for Basic Research №20-04-60450/21.Results: The postcovid period is characterized by a less pronounced degree of inhibition of antiviral activity with tendency to restoration of activity of IFN types I and II compared with acute stage of disease. The 2nd degree of insufficiency of ba IFN was noted in 51.1% of patients (I) and 27.7% (II), the 3rd degree of deficiency in 40.4% (I) and 44.7% (II). In 21.3% of surveyed, the inhibition of the IFNγ of severity 4 remained without a tendency to recovery for specified period of time in rehabilitation. We have noted: patients with a more severe form of COVID-19 have lower levels of ba IFN types I and II. Recovery of IFN status reveals positive dynamics up to 7 months after disease, however, a longer period of time is required for the full recovery of functionally ba IFN. Conclusion. The results of this study confirm the hypothesis of prevailing role of disturbance of IFNgenesis caused by the SARS-CoV-2 virus in immunopathogenesis of post-COVID-19 syndrome development.FootnotesCite this article as ERJ Open Research 2022; 8: Suppl. 8, 240.This article was presented at the 2022 ERS Lung Science Conference, in session “Poster Session 2”.This is an ERS Lung Science Conference abstract. No full-text version is available. Further material to accompany this abstract may be available at www.ers-education.org (ERS member access only).