Работа посвящена изучению особенностей регенерации костной ткани на модели экспериментальной костной раны кролика при использовании клеточно-инженерной конструкции, сформированной из ксеногенной коллагеновой матрицы («Коллатамп ИГ» Collatamp EG, «СинтколлГмбХ», Германия) и аллогенных мезенхимальных стволовых клеток костного мозга (МСК-КМ). С помощью методов флуоресцентной микроскопии показано, что МСК-КМ кролика сохраняют жизнеспособность и морфологическую однородность при культивировании на матрице («Коллатамп ИГ» Collatamp EG, «СинтколлГмбХ», Германия) в течение не менее 120 ч. Исследование in vivo выполнено на 25 кроликах породы «Серый великан». Фрезой диаметром 4,0 мм вдоль оси кости формировали стандартизированный дефект надкостницы, кортикального слоя и губчатого вещества размерами 8,0х4,0 мм и глубиной 4,0 мм. Сформированный дефект в опытной группе заполняли конструктом. Контрольная группа была представлена животными, у которых происходило спонтанное заживление костного дефекта. Наблюдение за размерами дефекта, особенностями формы и структуры костной ткани в области очага, его точным расположением, конфигурацией осуществляли в сроки 4, 8, 12 недель с помощью рентгенографии и гистологического исследования, выполненного с использованием световой микроскопии, с применением стандартных методов окрашивания. Проведенное исследование показало эффективность конструкции на основе аллогенных МСК-КМ и матрицы-«Коллатамп ИГ» (Collatamp EG, «СинтколлГмбХ», Германия), для восстановления дефектов костной ткани в эксперименте.

The aim of the study was to develop a technology for repairing an osteomyelitic bone defect using autologous adipose tissue mesenchymal stromal cells (MSCs) bound to a collagen matrix and to test the efficacy of this technique. Materials and Methods. The study was carried out with 17 rabbits. A bone defect was created using a milling cutter applied to the proximal third of the leg. The wound (8.0×4.0 mm and a depth of 4.0 mm) involved the periosteum, cortical layer, and cancellous substance. Staphylococcus aureus strain was used as an infectious agent. After the development of chronic osteomyelitis, the animals underwent osteonecrectomy. In the study group, autologous MSCs in Collatamp EG collagen carrier were placed into the bone defect. MSCs were obtained from adipose tissue and cultured in the matrix for 5 days. In control, the defect was filled with the collagen matrix without cells. Results. On day 14 upon the initiation of chronic osteomyelitis, bacteriological examination of the discharge from the fistula showed the presence of mixed bacterial flora (Staphylococcus aureus and Escherichia coli) in all operated animals. Results of X-ray, laboratory, and histological tests confirmed the formation of a focus of chronic osteomyelitis. Two months after the treatment (collagen with or without MSCs) began, all animals of the study group showed mature bone tissue regenerated in the affected zone. In the control group, proliferation of osteoblasts on the surface of the bone trabeculae was also observed; however, mature osteoid tissue was more often detected in the study group (35.0 vs 20.0% in control). In the study group (MSCs + collagen matrix), there was a decrease in bone marrow fibrosis (50.0 vs 100.0% in control) and cartilage formation (30.0 and 66.7%, respectively). After full treatment, newly formed bone trabeculae were detected more often (100.0 vs 60.0% in control); they were more mature and filled the defect area more efficiently. Conclusion. Our results indicate that the use of a collagen matrix with autologous MSCs is a promising plastic material for repairing osteomyelitic defects following necrectomy. The MSCs were able to increase the density of the filling material in the bone cavity, significantly accelerate the formation of bone beams around the matrix, and increase the tissue volume around the implant. The presence of MSCs significantly decreased the interference of a connective tissue component with osteogenesis and chondrogenesis.

Introduction. The article describes an experimental model of chronic suppurative osteomyelitis in a rabbit. As new therapeutic and diagnostic algorithms for the supervision of patients with osteomyelitis appear, there is an growing need to compare the methods of surgical debridement and plasty of bone defects in an infectious process, in order to create experimental standardized pathological conditions as close to the clinical course of the disease in humans as possible. The aim of the study was to develop an experimental model of a standardized chronic purulent bone cavity, suitable for a comprehensive assessment of surgical debridement effectiveness and osteoplastic properties of bone substitute materials. Materials and methods. A standardized defect of the tibia in 24 rabbits was formed. The Staphylococcusaureus strain was used as an infectious agent. A dynamic assessment of the main indicators of blood counts in animals was carried out. The formation of chronic osteomyelitis was evaluated using radiography, com-puted tomography methods and histological studies. Results. It was shown that purulent bone wound developed in experimental animals with the technique cre-ated, and a defect with signs of a chronic purulent-inflammatory process was demonstrated. Conclusion. The proposed model of chronic osteomyelitis is reproducible. Operational flexibility and identi-cal in size and location bone defects allow to use this model in new osteoplastic material research. Keywords: chronic osteomyelitis, experiment, experimental animals

Chronic ulcers are a common and socially significant problem worldwide. Autodermoplasty is the gold standard treatment for chronic ulcers. However, it is not always possible to perform this surgical procedure for a rather large group of patients, due to some reasons, which include high risk of autodermotransplant rejection, lack of donor material, and patient’s unwillingness to undergo surgery with an often unpredictable result. A potential solution to the problem is to use skin equivalents from allogeneic donor material. The use of allogeneic (donor) human cells makes it possible to fill the deficit of the patient’s donor resources and close wound without causing additional injury to the patient. This paper provides an overview of the application of foreign and domestic biomedical cell products in clinical trials and real clinical practice. We draw conclusions on the efficiency of the considered biomedical cell products in the treatment of chronic ulcers, evaluate the conducted research, and make recommendations on the most efficient use of allogeneic dermatotropic biomedical cell products.

Results of study of new osteoplastic material conditionally named «Kombas» were presented. That material consisted of nondemineralized animal collagen in a form of chips impregnated by vascular endothelium growth factor. The first step of experiment included in vitro study of the material was for cytotoxicity in diploid fibroblast cultures of 4-6 passages. At the second step purulent bone wounds were modelled in 36 Chinchilla rabbits. After debridement bone defect in the study group of animals (n=18) was filled with study material, in control group (n=18) the defect was not filled. Radiologic (X-ray, CT) and morphologic examination were performed at terms 1, 2 and 3 months. For objectification of the achieved data integral indices were proposed. Index of bone defect restoration in study group was 70% higher in 1 month, 47 % - in 2 months and 24% - in 3 months, as compared to the control group. In control group the index which characterized the completion of reparative processes exceeded that index in study group by 42% in 2 months and by 54% in 3 month of observation. Study results showed that elaborated material was not cytotoxic, possessed plasticity, marked osteoinductive and osteoconductive properties, as well as an ability to substitute bone tissue defects under conditions of purulent bone cavity in animal experiment.