Bacterial lysates in modifying sIgA levels in the upper respiratory tract in COVID-19 patients
Kostinov M. Chuchalin A. Svitich O. Gaynitdinova V. Mashilov K. Kryukova N. Osiptsov V. Tatevosov V. Khromova E. Baranova I. Vlasenko A. Shogenova L. Mekhantseva I. Khrapunova I. Linok A. Kostinov A. Polishchuk V. Poddubikov A.
December 2025Nature Research
Scientific Reports
2025#15Issue 1
A great deal of evidence has accumulated suggesting an important role of mucosal immunity not only in preventing COVID-19 but also in the pathogenesis of this infection. The aim of the study was to evaluate the levels of secretory immunoglobulin A (sIgA) in different compartments of the upper respiratory tract in COVID-19 patients in relation to the severity of the disease and treatment with a bacteria-based immunomodulating agent (Immunovac VP4). The titers of sIgA were determined by ELISA in nasal epithelial swabs, pharyngeal swabs, and salivary gland secretions at baseline and on days 14 and 30 of treatment. The levels of nasal, pharyngeal and salivary sIgA were significantly lower in more severe patients (subgroup A) than in less severe patients (subgroup B), p < 0.01. In subgroup A, the patients who received Immunovac VP4 had higher pharyngeal sIgA levels in convalescent period than those who did not receive the therapy p < 0.05. In subgroup B patients, an increase in immunoglobulin levels was observed from baseline to day 14 of treatment whether they received the add-on therapy or not, p < 0.01. On day 30 of treatment, the sIgA levels in the standard treatment group, however, decreased, while the patients receiving the immunomodulating agent maintained high sIgA levels, p < 0.05. Oxygen saturation significantly increased by day 14 in both groups, p < 0.001. However, it was higher in the Immunovac VP4 group than in the standard treatment group, p < 0.01. Thus, addition of a bacterial lysate-based immunomodulating agent to the treatment regimen for moderate-to-severe COVID-19 induces the production of pharyngeal and salivary sIgA. SIgA production is inversely correlated to CRP levels and percentage of lung involvement on CT scan and is directly correlated to SpO2 levels.
Bacterial lysates , COVID-19 , Immune therapy in COVID-19 , Microbial-based immunomodulating agent , Mucosal immunity , sIgA
Text of the article Перейти на текст статьи
I. Mechnikov Research Institute of Vaccines and Sera, Moscow, Russian Federation
I.M. Sechenov First Moscow State Medical University, Moscow, Russian Federation
Pirogov Russian National Research Medical University, Moscow, Russian Federation
Main Military Clinical Hospital of the Troops of the National Guard of the Russian Federation, Moscow, Russian Federation
Novokuznetsk State Institute for Advanced Training of Physicians, Branch Campus of the Russian Medical Academy of Continuous Professional Education, Novokuznetsk, Russian Federation
Karaganda Medical University, Karaganda, Kazakhstan
I. Mechnikov Research Institute of Vaccines and Sera
I.M. Sechenov First Moscow State Medical University
Pirogov Russian National Research Medical University
Main Military Clinical Hospital of the Troops of the National Guard of the Russian Federation
Novokuznetsk State Institute for Advanced Training of Physicians
Karaganda Medical University
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026