RESEARCH ON VARIOUS MODELS OF THE BIOLOGICAL EFFECTS OF COMPONENTS OF A COMPLEX EFFECT (PHOTOIRRADIATION; EXOSOMES OF MESENCHYMAL STEM CELLS AND NANOPARTICLES) FOR THE CORRECTION OF THE INFLAMMATORY PROCESS
Authors: Klimova O. M. , Bychenko К. О. 
Published: September 2023

Introduction. The search for new optimal methods for the treatment of chronic inflammatory processes is underway due to the growing antibiotic resistance. Physical, biological and chemical factors are used to correct the inflammatory process. Various sources of photoinfluence are widely used as physical factors. But the therapeutic effects of phototherapy are controversial, and the mechanisms of influence of different wavelengths on the immune response have not been studied. Another means for correcting metabolic disorders and stimulating regenerative processes is the successful use of stem cells of various origins, but local protocols forthe treatment of inflammatory processes using stem cells have not been developed.
Various nanoparticles are used for the treatment of inflammatory processes, stimulation of microcirculation and regeneration, and as an antioxidant. But there is conflicting information about the biological effects of these factors. And the use of all these factors is accompanied by a constant discussion about the possible mechanisms of their influence on the dynamics of local and systemic inflammatory processes and the biological safety of nanoparticles, in which the permissible doses and optimal sizes, which do not have a high degree of cytotoxicity, have not been determined.
It is relevant to study the mechanisms of changes in immunoresistance under the influence of different wavelengths of the visible light range during the main stages of the inflammatory process and to assess the potential for elucidating the potential of exosomes containing exometabolites of stem cells to stimulate the proliferative potential of immunocompetent cells of patients with chronic inflammation.
In the work, experimental studies were performed on 3 models. In models of induced inflammation, immunoresistance was studied at the stages of the inflammatory process after exposure to different wavelengths (λ = 660 nm, 530 nm, 470 nm).
In the work, the first stage of inflammation (infiltration) revealed the activation of innate immunity after exposure to red light (λ = 660 nm) in experimental animals with an induced inflammatory reaction. The indicators were higher than with the comparison group in animals with inflammation without photo exposure. Green light (λ = 530 nm) led to the normalization of cellular indicators and a decrease in humoral immunity in the second stage of inflammation (infiltration). Blue light (λ = 470 nm) contributed to the reduction of the studied indicators of immunity at the third stage of inflammation (proliferation). In each group of animals, after exposure to a certain wavelength, the duration of the stages of inflammation decreased relative to the comparison group (animals with induced peritonitis without exposure).
In the culture of cells of patients with chronic inflammatory processes, a pronounced stimulating effect was found after the action of exosomes of stem cells on proliferative activity in comparison with the mitogen FGA. The study of cytotoxicity using the cell bioindicator D. viridis of cerium dioxide nanoparticles with different characteristics made it possible to identify the optimal concentration and size of nanoparticles (2nm, 0.01M), which do not show a cytotoxic effect.
The complex application of the photoinfluence of SC exosomes and nanoparticles will allow the development of new treatment protocols for the correction of various homeostasis disturbances at the stages of the inflammatory process.
Material and Methods. In the work, indicators of immunoresistance after photoirradiation and exposure to exosomes of stem cells were studied on experimental models and objects. The possible cytotoxic activity of cerium dioxide nanoparticles of different concentrations and sizes was studied using the cellular bioindicator D. viridis.
Results. After exposure to red light (λ = 660 nm), activation of phagocytosis, stimulation of the formation of circulating immune complexes (CIC) and increased lymphocytotoxicity (LCT) were detected at the 1st stage of the inflammatory reaction. After the joint application of green light (λ= 530 nm) and the application of exosomes in the 2nd phase of the inflammatory reaction, the maximum positive effect and immune response was revealed, which was manifested by an increase in the absorptive capacity of neutrophils, a decrease in CIC and LCT. The use of blue light (λ = 470 nm) at the III stage of the inflammatory reaction contributed to the completion of the inflammatory process.
It was established that exometabolites of stem cells reveal a pronounced activation of proliferation in leukocyte culture in vitro. Exosomes have the ability to activate angiogenesis, proliferation, migration and differentiation of the main types of cells involved in the regeneration of inflammatory processes. When cultivating peripheral blood lymphocytes in vitro in patients with a chronic inflammatory process, a low spontaneous proliferative activity of cells was found, while with the use of MSC exosomes, the proliferative effect was significantly higher. Therefore, factors of microenvironment found in exosomes stimulated the synthetic activity of cultured lymphocytes.
Nanoparticles of cerium dioxide with a size of 2 nm and a concentration of 0.01M have no cytotoxicity (Is = 2.8 ± 0.09), and an increase in size to 4 to 6 nm in a concentration of 0.1 M has a high level of cytotoxicity (Is = 7.2 ± 0.31).
Conclusion. We conducted the research on the following models: I – experimental animals with LPS induced peritonitis. They found a correlation with the change in the effects of different wavelengths on indicators of immunoresistance; II – culture of peripheral blood leukocytes in vitro. Application of exosomes with exometabolites of mesenchymal stem cells induces proliferative activity in vitro in cell culture of patients with chronic inflammation; III model – investigated the possible cytotoxic activity of cerium dioxide nanoparticles of different concentrations and different sizes using the cellular bioindicator D. viridis.