No abstract

Lactobacilli are  widely used  in clinical  practice as probiotics, biologically  active  additives  and probiotic products for functional nutrition. Some  probiotics can  be considered as bacterial vaccines  due  to induction of immune response, accompanied by production of specific antibodies. The aim of the present study was to evaluate  the state of cellular and humoral immunity in women  by using probiotic strains of lactobacilli. The  study  included 31 healthy  women  aged  25-45  years.  As a source  of probiotic lactobacterial complex, we used  the  “Provag” preparation (RU  77.99.11.003.E.003746.02.11 of 11.02.2011, 1 capsule  contains 109 Lactobacillus  gasseri 57C,  Lactobacillus  fermentum  57A и Lactobacillus  plantarum  57B).  The  drug  was used for 30 days, at a rate  of one  capsule  per day. The  immune system was examined twice: before  administering the drug and after 30 days of treatment. The study of blood  lymphocyte populations and subpopulations was performed by flow cytometry using direct immunofluorescence technique. The concentration of IgA, IgM, IgG in blood serum was determined using enzyme  immunoassay. To determine specific antibodies, we used passive hemagglutination reaction with erythrocyte diagnosticum. The complex of probiotic lactobacilli Lactobacillus gasseri, Lactobacillus  fermentum  and  Lactobacillus  plantarum corresponding to the “Provag” preparation was used as a source  of antigen. It has been revealed  that  the number of T and B lymphocytes in peripheral blood increased after  30 days  of treatment with  the  probiotic preparation “Provag” in  healthy  women. Elevated contents of T cells was due to the T helper  cell fraction. Increased levels of T helpers and B lymphocytes were associated with stimulation of humoral immunity, as evidenced by increasing concentration of IgA and  IgG in blood  serum.  By means  of passive hemagglutination reaction, we have found  that  90% of healthy  women showed increased concentrations of specific IgA in blood after 30 days of treatment with “Provag” preparation.

No abstract

According to the modern concepts the respiratory burst directly related to the processes of phagocytosis characterizes the functional activity of phagocytic cells. This review presents modern methods for assessing the respiratory burst state of phagocytes based on cytofluorometric and chemiluminescent analysis. The sequence and mechanisms of the reactions of reactive oxygen species (ROS) synthesis in the process of respiratory cell burst are presented in detail. The sequence of synthesis from ROS with low bactericidal activity to ROS with high bactericidal activity is characterized. The review describes in detail the most popular dyes for cytofluorometric analysis to assess the levels of ROS synthesis. Characteristics and examples of the use of such dyes as dihydroethidine, dichlorodihydrofluorescein and dihydrorhodamine 123 are given. The main stages and mechanisms of the chemiluminescence reaction are presented. The features of the use of the main indicators (luminol and lucigenin) of the chemiluminescence reaction are described. A mechanism for estimating the parameters of the chemiluminescence reaction characterizing the features of the state and kinetics of the respiratory burst of phagocytic cells is given. The separate section of the review is devoted to the role of a respiratory burst in phagocytic cells in various immunopathological states. Data on the pathogenetic significance of changes in the intensity and kinetics of respiratory burst of phagocytes in infectious, inflammatory and oncological diseases were presented. Examples of new methods for diagnosing and predicting the course of the immunopathological states characters are presented on the basis of an assessment of the respiratory burst of phagocytic cells. The literature data show that at present, in the diagnosis and evaluation of the nature of the diseases characters the state of a respiratory burst is evaluated in various types of cells of innate immunity: neutrophils, monocytes, etc. It is concluded that the evaluation of the respiratory burst of phagocytic cells can be characterized as the fundamental mechanisms of reacting cells of innate immunity to pathogenic and regulatory effects, so to develop new highly sensitive methods for diagnosing and predicting the development and outcome of various immunopathological conditions. The presented methods of flow cytometry and chemiluminescence analysis make it possible to determine both the integral state of the respiratory explosion, and the levels and kinetic parameters of the synthesis of individual ROS.

Post-COVID syndrome develops in 10–20% of people who have recovered from COVID-19 and it is characterized by impaired function of the nervous, cardiovascular, and immune systems. Previously, it was found that patients who recovered from infection with the SARS-CoV-2 virus had a decrease in the number and functional activity of NK cells. The aim of the study was to assess the effectiveness of recombinant human IL-2 (rhIL-2) administered to correct NK cell phenotype and functional activity in patients with post-COVID syndrome. Patients were examined after 3 months for acute COVID-19 of varying severity. The phenotype of the peripheral blood NK cells was studied by flow cytometry. It was found that disturbances in the cell subset composition in patients with post-COVID syndrome were characterized by low levels of mature (p = 0.001) and cytotoxic NK cells (p = 0.013), with increased release of immature NK cells (p = 0.023). Functional deficiency of NK cells in post-COVID syndrome was characterized by lowered cytotoxic activity due to the decreased count of CD57+ (p = 0.001) and CD8+ (p < 0.001) NK cells. In the treatment of patients with post-COVID syndrome with recombinant IL-2, peripheral blood NK cell count and functional potential were restored. In general, the effectiveness of using rhIL-2 in treatment of post-COVID syndrome has been proven in patients with low levels of NK cells.

Background: T and B cell-mediated immunity can be assessed using T cell receptor excision circle (TREC) and Kappa-deleting recombination excision circle (KREC) analysis, respectively, and successful implementation of this method requires evaluation of the correlation between the TREC frequencies and T cell subsets as well as KREC levels and B lymphocyte subsets. The aim of the present study was to evaluate the correlation between the TREC/KREC concentrations and T/B lymphocyte subsets at different stages of COVID-19. Methods: We examined 33 patients in the acute stage of COVID-19 (including 8 patients with poor outcomes) and 33 COVID-19 survivors. TREC/KREC concentrations were measured using quantitative real-time PCR. T/B lymphocyte subsets were determined using flow cytometry. Results: Blood TREC and KREC levels were found to be significantly lower in the acute stage of COVID-19 compared to control values. Moreover, a zero blood TREC level was a predictor of a poor disease outcome. Reductions in CD3+CD4+CD45RO−CD62L− and CD3+CD8+CD45RO−CD62L− T cell counts (as well as in the main fractions of B1 and B2 B cells) indicated a favorable outcome in COVID-19 patients in the acute stage of the disease. Decreased CD3+CD4+CD45RO−CD62L+ and CD3+CD8+CD45RO−CD62L+ T cell frequencies and increased CD3+CD8+CD45RO−CD62L− cell counts were found to indicate a poor outcome in patients with acute COVID-19. These patients were also found to have increased B1 cell counts while demonstrating no changes in B2 cell counts. The levels of effector T cell subsets an naïve B cells were normal in COVID-19 survivors. The most pronounced correlations between TREC/KREC levels and T/B cell subsets counts were observed in COVID-19 survivors: there were positive correlations with naïve T and B lymphocytes and negative correlations with central and effector memory T cell subsets. Conclusions: The assessment of correlations between TREC and T cell subsets as well as KREC levels and B cell subset counts in patients with acute COVID-19 and COVID-19 survivors has shown that blood concentrations of TREC and KREC are sensitive indicators of the stage of antigen-independent differentiation of adaptive immunity cells. The results of the TREC and KREC analysis correlated with the stages of COVID-19 and differed depending on the outcome of COVID-19.

Резюме. Целью исследования явилось изучение состояния клеточного и гуморального иммунитета у больных с распространенным гнойным перитонитом (РГП) в зависимости от исхода заболевания. Обследовано 50 больных РГП внебольничного и госпитального происхождения. Исследование фенотипа лимфоцитов крови проводили методом проточной цитометрии. Концентрацию иммуноглобулинов и цитокинов определяли иммуноферментным методом. Установлено, что состояние иммунной системы при РГП характеризуется лейкоцитозом, относительной лимфопенией, увеличением концентрации провоспалительных цитокинов, а также снижением содержания цитотоксических и активированных Т-лимфоцитов. Состояние клеточного звена иммунной системы при неблагоприятном исходе РГП характеризуется снижением уровней γδТ-лимфоцитов и NKT-клеток при повышении количества В1-лимфоцитов. Состояние иммунной системы при благоприятном исходе РГП характеризуется снижением количества NK-клеток в периферической крови и повышением содержания Th2-лимфоцитов. Увеличение количества Th2-клеток определяет усиление стимулирующего влияния Т-клеточного звена на гуморальный иммунитет, что проявляется в увеличении концентраций IL-4 и IgA, что и является важным фактором в иммунопатогенезе РГП, определяющим его благоприятный исход.

Савченко А.А. и др. Medical Immunology (Russia)/Meditsinskaya Immunologiya Медицинская Иммунология вых людей и больных РП выравнивается, но при РП меньше формируется аДК с высокоактивным фенотипом (CD83 + CD80 high CD86 high и CD83 + CD80 high CD86 high HLA-DR +). Более того, при онкологии аДК с фенотипом CD83 + CD80 high CD86 high слабее экспрессируют рецепторы для проявления костимуляторной и антигенпрезентирующей активности. Различия в фенотипе нДК и аДК у здоровых людей и больных РП могут определяться различиями в фенотипе и функциональной активности моноцитов крови и иммунодепрессивными факторами, синтезируемые опухолью.