Bronchial asthma can occur for several reasons. Bacteria that live in the patient's lungs and intestines may play a key role in the development of the disease. If the microbiota is disturbed, it causes negative consequences for the immune system and can provoke diseases. At the same time, the details of the relationship between asthma, immunity and microbiota are not yet known to scientists. Understanding these processes will help treat asthma, not just fight its symptoms.
“Many medications help control asthma attacks, but there is still no effective therapy. Therefore, the identification of the causes of asthma and its prevention remain an urgent task. Bacterial components formed during the degradation of commensal microflora are necessary for the normal development of the immune system and the formation of an adequate immune response,” said Svetlana Guryanova, PhD, associate professor of the Department of Biology and General Genetics at RUDN University.
The biologists chose two key components of the bacterial cell wall as the object of study - lipopolysaccharides (LPS) and muramyl dipeptide (MDP). These low molecular weight bioregulators interact with receptors, as a result of which an immune response is formed - a balance of inflammatory and anti-inflammatory processes. Violation of this interaction leads to pathologies - chronic inflammation, autoimmune and allergic reactions, asthma.
For the study, RUDN scientists injected laboratory mice with albumin to simulate asthma symptoms. The animals were divided into 6 groups and administered in different combinations of albumin, LPS and MDP, and then the condition of the bronchi was compared. The introduction of LPS and MDP increased the content of cells that are responsible for the immune response by 1.5-2 times: macrophages, neutrophils, lymphocytes and eosinophils. Moreover, if repeatedly administered at low concentrations of LPS and MDP before the administration of albumin, the level of these cells decreases.
“Experiments for the first time demonstrated the dual effect of bacterial components in an asthma model: if they are administered before the antigen, allergic inflammation manifests itself to a lesser extent, while co-administration with the antigen contributes to a more pronounced inflammatory process. Our results provide a new understanding of the mechanisms of allergic inflammation, with their help, after appropriate clinical studies, it is possible to optimize the treatment and prevention of asthma,” said Svetlana Guryanova, PhD, associate professor of the Department of Biology and General Genetics at RUDN University.(KF/Newswise)