The creation of bioengineered tissue/organ equivalents is closely related to the development of biodegradable, highly porous 3D scaffolds, which to some extent provide the microenvironment necessary to maintain the viability of the cellular component. According to many researchers, the most interesting are tissue-specific matrices that can selectively support the adhesion, proliferation, and differentiation of tissue cells of those organs from which they are obtained by decellularization. It was shown that, during intramuscular implantation in rats of decellularized pig liver fragments (DLFp), independent of the method of removal of detergent residues (96 h of washing in phosphate-buffered saline (PBS) or combined: 24 h in PBS and 8 h with supercritical CO2 (sc-CO2)), the samples meet the requirements for medical devices in terms of local and general toxic effects. Thus, the use of sc-CO2 made it possible to reduce the duration of the technology for producing biocompatible tissue-specific matrices based on DLFp by 3 times. Moreover, when using sc-CO2 at the stage of washing the DLFp matrix, a “mild reaction” of the tissue to the sample is observed during 2 months of intramuscular implantation of the matrix in rats with its complete resorption after 3 months of the experiment. Under the same conditions, the duration of a similar local action of DLFp washed in the PBS on the tissue is 3 months with degradation of 63% of the matrix of the sample size.

Aim. A study of biocompatible and matrix properties of polylactide scaffolds as a materials for medical implanted articles as well as scaffolds for cell and tissue engineering constructions.Materials and methods. Biocompatibility of polylactide scaffolds in the form of porous disks obtained by freeze drying method was estimated in vitro: by UV spectroscopy, pH measurements and cytotoxicity to NIH/3T3 mice fi broblasts in static conditions. Biocompatibility of scaffolds in vivo was investigated by its implantation under mice skin. Matrix properties of polylactide scaffolds (cell adhesion and proliferation) were studied in dynamic conditions with mesenchymal stromal cells of human adipose tissue (MSC ADh) in perfusion bioreactor. Results. As a result of in vitro investigations it was shown that polylactide scaffolds obtained by freeze drying are satisfi ed to demands presenting biocompatible medical articles with respect to pH measurements, extraction tests and cyto toxicity to mice fi broblasts NIH/3T3. Cultivation of MSC ADh in perfusion bioreactor in hepatogenic media is accompanying by good adhesion and proliferation both on the surface and in the bulk of porous disks. However implantation of polylactide scaffolds under mice skin is accompanying by resorption and leads to the infl ammation reaction of adjacent tissues. Conclusions. Positive results obtained only by in vitro testing of biocompatibility and matrix properties are not enough to recommend the material to be used as a scaffolds for cell and tissue engineering constructions. The preliminary study of biomechanical characteristics of the implant is recommended.

An in vivo study of the biological safety of a biomedical cell product for regeneration of articular cartilage with subcutaneous implantation of cell-engineered cartilage tissue was carried out. A comparative study of the biological safety of the cell-engineered construct of human articular cartilage tissue (CEC hAT) and the biocompatible BMCH matrix in an implantation test did not show significant differences between the control and experimental groups. The results demonstrated that the cell component of the cell-engineered construct of hAT is not a risk factor for its implantation for up to 28 days. During the study, some signs of formation of articular tissue were observed at the site of subcutaneous implantation of the CEC hAT. Considering high proliferation and differentiation activity of the CEC hAT previously confirmed after its cultivation for 42 days, it is possible to suggest the potential of using CEC hAT for regeneration of injured cartilage as an injection form of biomedical cell product.

The aim of this study is an analysis of the functional effectiveness of a biomedical cell product consisting of a biopolymer microheterogeneous collagen-containing hydrogel (BMCH), human adipose-derived mesenchymal stromal cells (hADMSCs), and chondrogenic induction medium in the regeneration of articular cartilage. Materials and methods. The test model of the adjuvant arthritis was used (female Soviet Chinchilla rabbits) with the further development into osteoarthrosis (OA) combined with the clinical, biochemical, radiological, and histochemical trials. Results. On Day 92 of the OA model it has been found that the intra-articular introduction of a BMCH with hADMSCs into the left knee joint (n = 3) 30 days after the OA modeling, as opposed to the right joint (negative control, n = 3), stimulates the regenerative processes of the cartilaginous tissue structure characterized by the formation of chondrocyte «columns», the emergence of isogenic groups in the intracellular matrix and the regeneration of its structure. Upon the intra-articular introduction of a BMCH (n = 3) such effects are markedly less pronounced. Conclusions. A significant regenerative potential of a cell-engineered construct of human articular tissue (CEC ATh) has been proven. It is possible to presume that biostimulating properties of CEC ATh are due to the activating effect of a biomedical cell product on the stem cell migration processes from the surrounding tissue into the injured area with their subsequent differentiation.

An in vivo study of the biological safety of a biomedical cell product for regeneration of articular cartilage with subcutaneous implantation of cellengi neered cartilage tissue was carried out. A comparative study of the biological safety of the cellengineered co nstruct of human articular cartilage tissue (CEC hAT) and the biocompatible BMCH matrix in an implantation test did not show significant differences between the control and experimental groups. The results demonstrated that the cell component of the cellengineered construct of hAT is not a risk factor for its implantation for up to 28 days. During the study, some signs of for� mation of articular tissue were observed at the site of subcutaneous implantation of the CEC hAT. Consider� ing high proliferation and differentiation activity of the CEC hAT previously confirmed after its cultivation for 42 days, it is possible to suggest the potential of using CEC hAT for regeneration of injured cartilage as an injection form of biomedical cell product.