At present there is a growing need for tissue engineering products, including the products of scaffold-technologies. Biopolymer hydrogel scaffolds have a number of advantages and are increasingly being used to provide means of cell transfer for therapeutic treatments and for inducing tissue regeneration. This work presents original hydrogel biopolymer scaffolds based on a blood plasma cryoprecipitate and collagen and formed under conditions of enzymatic hydrolysis. Two differently originated collagens were used for the scaffold formation. During this work the structural and mechanical characteristics of the scaffold were studied. It was found that, depending on the origin of collagen, scaffolds possess differences in their structural and mechanical characteristics. Both types of hydrogel scaffolds have good biocompatibility and provide conditions that maintain the three-dimensional growth of adipose tissue stem cells. Hence, scaffolds based on such a blood plasma cryoprecipitate and collagen have good prospects as cell carriers and can be widely used in regenerative medicine.

The activity of stem cell processes is regulated by internal and external signals of the cell “niche”. In general, the niche of stem cells can be represented as the microenvironment of the cells, providing a signal complex, determining the properties of the cells. At the same time, the “niche” concept implies feedback. Cells can modify their microenvironment, supporting homeostasis or remodeling the composition and structure of the extracellular matrix. To ensure the regenerative potential of tissue engineering products the “niche” concept should be taken into account. To investigate interactions in an experimental niche, an original hydrogel biopolymer scaffold with encapsulated mesenchymal adipose-derived stem cells (ASCs) was used in this study. The scaffold provides for cell adhesion, active cell growth, and proliferative activity. Cells cultured within a scaffold are distinguished by the presence of a developed cytoskeleton and they form a cellular network. ASCs cultured within a scaffold change their microenvironment by secreting VEGF-A and remodeling the scaffold structure. Scaffold biodegradation processes were evaluated after previous culturing of the ASCs in the scaffolds for periods of either 24 h or six days. The revealed differences confirmed that changes had occurred in the properties of scaffolds remodeled by cells during cultivation. The mechanisms of the identified changes and the possibility of considering the presented scaffold as an appropriate artificial niche for ASCs are discussed.

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Porous polymer materials derived from poly(ethylene glycol dimethacrylate) (poly‐EGDMA) and antibiotic containing polylactide (PLA) are obtained for the first time. Porous poly‐EGDMA monoliths with a system of open interconnected pores are synthesized by a visible light‐induced radical polymerization of EGDMA in the presence of 70 wt% of porogenic agent, e.g., 1‐butanol, 1‐hexanol, 1‐octanol, or cyclohexanol. The porosity of the obtained polymers is 75–78%. A modal pore size depends on the nature of the porogen and varies from 0.5 µm (cyclohexanol) to 12 µm (1‐butanol). The polymer matrix made with 1‐butanol features the presence of pores ranging from 1 to 100 µm. The pore surface of poly‐EGDMA matrices is inlayered with poly‐D,L‐lactide (Mn 23 × 103 Da, PDI 1.31). The PLA‐modified poly‐EGDMA retains a porous structure that is similar to the initial poly‐EGDMA but with improved strength characteristics. The presence of antibiotic containing PLA ensures a high and continuous antibacterial activity of the hybrid polymeric material for 7 days. The nontoxicity of all the porous matrices studied makes them promising for clinical tests as osteoplastic materials.