THE ACTIVATION OF THE DERMIS EXTRACELLULAR MATRIX SYNTHESIS AFTER THE THERMAL BURN

Abstract

It is known that the healing of skin wounds of various etiologies is a multistage process characterized by certain intercellular interactions that affect the adhesion of dermal cells, their migration and differentiation. The modern strategy of tissue engineering mostly attracted for the use of the patient's own cells to create in vitro a vascularized extracellular matrix, which is characterized by the absence of exogenous material, which brings the regeneration process identity to the physiological one. The aim of this study was the morphological transformations of the dermis in the burn area using a biodegradable calcium-containing filler, which acts as a dynamic and multifunctional regulator of the cellular activity of the dermis. The study was performed on 30 laboratory outbred rats. All animals were given a third-degree burn, then the animals were divided into two groups: control and experimental. On the 14th day after the application of the burn, the rats of the experimental group were injected with an injectable implant preparation based on calcium hydroxyapatite «Radiesse». In the group of control animals, sterile saline was used. Biological material was taken at the time corresponding to 2 and 4 months. To assess the morphological state of the burn zone, histological sections of skin preparations were stained with hematoxylin and eosin, according to Mallory, Masson and Van Gieson. Collagen types I and III were also determined by immunohistochemistry. The data obtained suggest that the use of a calcium-containing filler is promising for skin regeneration after a burn and can provide an extracellular matrix of the dermis with a composition and architecture of a collagen network close to natural. Differentiated detection of type I and III collagens confirmed the activation of the rate of collagen synthesis by fibroblasts in both the dermis of the burn zone and in the implant zone by the end of the second month. The assessment of the tissue entropy index confirms the similarity of the structural organization as dermis of the natural as restored after the burn and the use of the preparation. The strategy proposed in the experiment, using the body's own cells to synthesize an extracellular matrix similar to the natural one, can be an alternative to existing methods of burn treatment.