TISSUE IMMUNE CELLS AND THEIR ROLE IN THE HEALING PROCESS OF INFECTED RADIATION ULCERS UNDER THE IMPACT OF PHOTODYNAMIC THERAPY (EXPERIMENTAL STUDY).

Abstract

OBJECTIVE\nto study the effect of antibacterial photodynamic therapy (PDT) on the dynamics of tissue neutrophilic leukocytes CD18 and tissue macrophages ED1 in the tissues of infected radiation ulcer during the stages of sponta- neous healing and in the treatment of PDTMaterials and methods. Infected radiation ulcer was modeled by local X-ray irradiation of the rat thigh skin at a dose of 85.0 Gy, followed by applying to the surface of the ulcer bacterial suspension of S. аureus. PDT was performed using a «Barva-LED/630» photonic apparatus and a methylene blue photosensitizer. The effect of PDT on the state of cellular immunity was determined using an immunohistochemical method based on the quantitative indices of neutrophilic leukocytes CD18 and ED1 macrophages during the stages of healing of an infected radiation ulcer.\n\n\nRESULTS\nIn the course of spontaneous healing of the ulcer (control I), the dynamics of changes in the relative vo- lume of tissue neutrophil leukocytes CD18 and ED1 macrophages in the lesion zone, a decrease in the CD18 / ED1 index more than 2 times indicated that switching of the neutrophil response to macrophage occurred before 52nd days of observations. When infected with S. аureus X-ray (control II), the switching of the neutrophil response to the macrophage did not occur during the entire observation period. When using PDT in the case of S. аureus infected ulcer (experimental group), the decrease in the CD18 / ED1 index was determined from the 21st day of observation.\n\n\nCONCLUSIONS\nThe positive effect of the antibacterial PDT method of infected S. аureus radiation ulcers was manifes- ted by complete microbial decontamination of the wound, reduction of phases of the wound process, complete hea- ling of radiation ulcers.The use of PDT has led to the death of bacteria, a decrease in the number of neutrophilic leukocytes and an increase in macrophages in the lesion area, the switching of the neutrophilic response to the reaction of monocyte-macrophage cells in the early stages of healing.