CHANGES OF INNATE IMMUNITY INDEXES IN SEVERE ASTHMA IN CHILDREN

At the present time, the role of innate immunity in pathogenesis of bronchial asthma (BA) is actively studied, in particular, significance of TLRs and cytokines. The study included 42 patients with severe bronchial asthma (from 3 to 12 years old), and 67 healthy children at the same age. Expression of TLR2, TLR4, and TLR9 genes was evaluated by PCR-RT from the scrapings of nasal mucosa; cytokines (IL-33, TSLP, IL-4, TGF-β1 and IL-28B) were assayed in nasal swabs by ELISA technique. The main results were as follows: an increased gene expression of TLR2, TLR4, TLR9 genes was revealed in the nasal mucosa scraps from the patients with bronchial asthma as compared to healthy children. We have also measured the contents of important cytokines secreted by the respiratory epithelium in the course of TLRs activation. The study of IL-33, TSLP, IL-4 in nasal samples revealed significantly increased concentrations of these cytokines in the patients with severe BA against the control group. A study of TGF-βlevels in nasal cavity swabs revealed a significant decrease of this regulatory cytokine in the group of pediatric patients with asthma. Worth of note, evaluation of antiviral IL-28B cytokine in the group of patients with severe BA showed a significant downward trend, in comparison to the control indexes. Hence, one may conclude on some disturbances of local innate immunity system in the patients with severe BA which manifest as hyperexpression of TLRs genes, increased production of proinflammatory and epithelial cytokines, decreased production of antiviral IL-28B cytokine, and TGF-β1

The role of epithelial cells in atopy pathogenesis

Aim. The study of the mechanisms of atopic disease formation and a model of immunopathogenesis of the atopic diseases.Methods. Determination of surface lymphocytes receptors in peripheral blood of atopic bronchial asthma and atopic dermatitis patients with the help of monoclonal antibodies using the indirect immunofluorescence method. Expression of genes encoding TLR2, TLR4 and TLR9 receptors of airborne epithelial cells by real-time polymerase chain reaction, as well as determination of cytokine TSLP, IL-33, IL-4 and TGFβ (eBioscience) in airway flushes in atopic asthma patients and healthy people.Results. During the exacerbation of atopic diseases in peripheral blood lymphocytes, an intensive activation process develops with impaired lymphocytes activating apoptosis aimed at the formation of plasma cells capable of developing intensive IgE synthesis. To search for signals that could explain the mechanism of rearrangement of the B-cell part of the immune system during atopy, the epithelium cells of the airways were examined in a group of patients with atopic asthma and found an increase in gene expression coding for TLR2, TLR4, TLR9 in 6, 3 and 2.5 times respectively. Along with increased expression of TLRs genes in patients with bronchial asthma, an increased content of TSLP and IL-33 cytokines secreted by epithelial cells of the airways was detected. These cytokines have an immunoregulatory action - their nearby antigen presenting functions format the Th2 type of immune response, promote the production of cytokines (IL-4, IL-9, IL-13) and cause the development of an allergic type of inflammation.Conclusion. We suppose that the main link in pathogenesis is a disruption of the interaction of TLRs with the corresponding ligands caused by spontaneous dimerization of TLRs under the malonic dialdehyde influence. The intake of slowly metabolized dimers of TLRs into epithelial cells is a signal for genome activation, which leads to the synthesis of allergic cytokines IL-33 and TSLP. Thus, the main immunopathogenesis pathway of atopic diseases is the pathological functional interaction between epithelial cells and peripheral blood B-lymphocytes

EXPRESSION FEATURES OF TOLL-LIKE RECEPTOR 2 AND TOLL-LIKE RECEPTOR 4 IN CHILDREN WITH ASTHMA

Currently actively  discussed  the  role  of innate immunity receptors, in particular TLRs  in the immunopathogenesis of bronchial asthma (BA).The aim of our work was to study the expression of ТLR2 and TLR4 on the nasal mucosal cells and peripheral blood leukocytes  of patients with BA of different  severity.The study included 40 children with asthma (3-12 years) and 10 healthy  children. Methods: real-time PCR, flow cytometry and multiplex immunofluorescence analysis evaluated the levels of pro and anti-inflammatory cytokines (IL-1β, IL-1ra, IL-6, IL-8, IL-10, TNFα) in nasal swabs.The result of the study hyperactivation of the factors of innate immunity at the level of the mucosal  of the nasal cavity in patients with asthma, manifested by increased gene expression  of TLR2, TLR4, and production of proinflammatory as well as anti-inflammatory cytokines. Correlation between cytokine levels and the severity of asthma. In the  peripheral blood  identified a significant  increase  in the  expression  of TLR2  and  TLR4  on circulating CD14+  monocytes in children with BA.Thus,  the  increase  of gene expression  of TLRs  mucosa of the  nasal cavity, increase  surface  expression  of TLR2  and TLR4  on circulating monocytes of patients with bronchial asthma compared to healthy  children. The revealed changes indicate the involvement of the system of TLRs in the immunopathogenesis of bronchial asthma. In the future, TLRs can be used as markers  to predict the course of ad and possible therapeutic targets