TY - JOUR T1 - Assessment of mucosal and systemic phagocytosis in Health Care Professionals (HCPs) in the post COVID-19 period JF - ERJ Open Research JO - erjor DO - 10.1183/23120541.LSC-2022.208 VL - 8 IS - suppl 8 SP - 208 AU - Nadezda Kryukova AU - Natal'Ya Abramova AU - Ekaterina Khromova AU - Svetlana Skhodova AU - Irina Bisheva AU - Dmitry Pakhomov AU - Aleksandra Vinnitskaya AU - Mikhail Kostinov AU - Irina Baranova AU - Oxana Svitich Y1 - 2022/03/10 UR - http://openres.ersjournals.com/content/8/suppl_8/208.abstract N2 - Phagocytic component of mucosal immunity in individuals infected with SARS-CoV-2 virus and COVID-19 convalescents is an understudied area. An important role in understanding haemophagocytic lymphohistiocytosis syndrome was played by the Russian researcher I.I. Mechnikov.Aims and objectives: To evaluate phagocytic component of respiratory mucosal immunity and a general level of phagocytic activity in blood of HCPs with COVID-19 history and ones without it.Materials and methods: Сross-sectional study included 182 HCPs (161 F/21 M, aged 47.3±12.7) after 125.1±71.1 days from the disease onset. Participants were divided into 4 groups: 1- severe, 2- moderate, 3- mild disease in history, 4- no disease. The examination included saliva, induced sputum, naso- and oropharyngeal mucosa scrapings, and venous blood samples. Phagocytic activity of blood leukocytes was determined by a cytofluometry flow in reaction with FITC-labeled staphylococci. Phagocytic activation index was determined by nitroblue tetrazolium reduction test.Results: The level of phagocytic index of granulocytes in the 2nd group (95,53±4,06) differed from the 3rd group (97,02±3,02) and from the 4th (97,44±1,89), p<0,05. Reduced reserve of bactericidal activity was observed in persons of 1rd and 2nd groups (1.99±0.75 and 2.27±0.88 respectively) compare to the 4th group (2.71±1.37; p<0.05). Values of phagocytic index of salivary granulocytes were lower in the group with severe disease (27,74±18,71) in comparison with HCPs without COVID-19 (48,82±27,42; p<0,05).Conclusion: The revealed changes indicate dysregulation of the innate immune response in the post COVID-19 period at the level of the mucosa as well as in blood.FootnotesCite this article as ERJ Open Research 2022; 8: Suppl. 8, 208.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). ER -