[Experimental validation of the developing a matrix based on decellularized vascular wall for subsequent substitution urethroplasty].

Urethral strictures are urgent urological problem. Anastomotic and substitution urethroplasty are the most effective treatments. For substitution urethroplasty, buccal mucosa is most often used. There are the following difficulties associated with the substitution urethroplasty: complications in the donor area, the lack of tissue for substitution, an additional incision, and increased timing of surgery due to the need to obtain a flap or graft. Tissue engineering can be useful in solving the above problems. Tissue engineering involves the use a matrix without cells and matrix with one or more types of cells (tissue-engineering designs). In our study we have evaluated the ability to create a matrix for the substitution urethroplasty in animal experiments. The decellularized cadaveric arterial wall was used as a matrix. Decellularization was performed using enzymatic method. At the first stage, we transplanted matrix fragments in interscapular region in rats. An extremely weak bioactivity dof decellularized matrix of cadaveric arterial wall (DMCAW) due to the low immunogenicity of the material was revealed. Thus resorption of DMCAW was quite slow (60-90 days). At the second stage, in an experiment on rabbits, substitution urethroplasty using tubular DMCAW was successfully performed. Intraoperative urethral defect up to 1.8 cm was created, which was replaced by a tubular DMCAW. The use of this type of matrix has showed good structural and functional results: urethral strictures did not arise, the rejection of the matrix was not observed. A slow degradation of the matrix and progressive epithelialization of onnective tissue capsule were revealed. Decellularized matrix based on cadaveric arterial wall can be considered as a material for substitution urethroplasty.

[Regulation of human dendrite cells' physiological functions with the recombinant heat shock protein Hsp70].

Reference literature review. The dendrite cells (DC) are the most important antigen-representing cells of the organism. They are the target for various vaccines, and on the basis of the DC cellular anti-tumour and anti-viral vaccines (DC vaccines) have been developed. At the same time, the DC can be a convenient model for studying activity and action mechanisms of different immune-therapeutic preparations. One of the aspects of the DC use optimization for induction of antigen-specific immune response might involve use of the heat shock proteins (Hsp), the Hsp70 in particular. This protein can be used for administration of protein antigens into the DC and for regulation of the DC activity. Knowledge of the DC physiology and specifics of interrelationship among the Hsp70 and its complexes with the DC antigens of different differentiation degree is an important aspect for implementation of these ideas. Human Hsp70 has been shown both to bring antigens to the DC and to regulate activity of the DC as well as to optimize induction of antigen-specific cellular immune response.