A. S. Sotnichenko

Orthotopic transplantation of a tissue engineered diaphragm in rats.

The currently available surgical options to repair the diaphragm are associated with significant risks of defect recurrence, lack of growth potential and restored functionality. A tissue engineered diaphragm has the potential to improve surgical outcomes for patients with congenital or acquired disorders. Here we show that decellularized diaphragmatic tissue reseeded with bone marrow mesenchymal stromal cells (BM-MSCs) facilitates in situ regeneration of functional tissue. A novel bioreactor, using simultaneous perfusion and agitation, was used to rapidly decellularize rat diaphragms. The scaffolds retained architecture and mechanical properties and supported cell adhesion, proliferation and differentiation. Biocompatibility was further confirmed inxa0vitro and inxa0vivo. We replaced 80% of the left hemidiaphragm with reseeded diaphragmatic scaffolds. After three weeks, transplanted animals gained 32% weight, showed myography, spirometry parameters, and histological evaluations similar to native rats. In conclusion, our study suggested that reseeded decellularized diaphragmatic tissue appears to be a promising option for patients in need of diaphragmatic reconstruction.

Evaluation of the influence of decellularization on the changes in biomechanical properties of primate lungs

The effect of decellularization on the biomechanical properties of macaque lungs was studied. The quality of the biological scaffold was additionally assessed by morphological methods, and the contents of extracellular matrix (ECM) fibers were determined both qualitatively and quantitatively. Histological analysis revealed no damage of structural integrity of ECM components, but the scaffold elasticity significantly decreased, which was confirmed by the changes in the hysteresis loop without a concomitant decrease in peak loads, with the mechanical strength of the samples being retained. These changes require taking additional measures to prevent a decrease in the effective lung volume.

Angiogenesis mechanisms in transplantation of tissue-engineered constructions

ВВЕДЕНИЕ Регенеративная медицина, основанная на использовании клеточных механизмов восстановления структур и функций организма, является фундаментальной основой медицины будущего, призванной избавить человечество от многих заболеваний [1]. Данная область является одной из наиболее высокотехнологичных и бурно развивающихся отраслей биомедицинской индустрии [2]. Одной из ключевых задач тканевой инженерии является формирование тканеинженерных конструкций (ТИК), которые могут использоваться в DOI: 10.15825/1995-1191-2017-4-141-145

The Effectiveness of Preimplantation Recellularization of Acellular Rat-Esophagus Matrices Using GFP-Positive Cells

The use of recellularized matrices allows obtaining tissue-engineered structures that largely reproduce the morphofunctional features of native organs and tissues. Doubts as to the advisability of preimplantation recellularization of the scaffold, which are associated with the death of prepopulation cells on the scaffold in vivo, require studying the behavior of cells on plastic and biological implants after recellularization. Rat esophagus that had undergone detergent-enzymatic decellularization was repopulated with GFP-positive cells intensely fluorescing in the green spectrum, which allowed us to trace the status of the initial cell population during cultivation on plastic and after transplantation, determine the viability and metabolic activity of cells, and conduct fluorescent detection of the cells on the scaffold before and after implantation. There were no data on the apparent cell proliferation on the matrix; however, there were indirect indications of metabolic activity and GFP synthesis by the cells that populated the scaffold before implantation.

In Vivo Experimental Study of Biological Compatibility of Tissue Engineered Tracheal Construct in Laboratory Primates

Biological compatibility of a tissue engineered construct of the trachea (synthetic scaffold) and allogenic mesenchymal stem cells was studied on laboratory Papio hamadryas primates. Subcutaneous implantation and orthotopic transplantations of tissue engineered constructs were carried out. Histological studies of the construct showed chaotically located filaments and mononuclear cells fixed to them. Development of a fine connective tissue capsule was found at the site of subcutaneous implantation of the tissue engineered construct. The intact structure of the scaffold populated by various cell types in orthotopic specimens was confirmed by expression of specific proteins. The results indicated biological compatibility of the tissue engineered construct with the mesenchymal stem cells; no tissue rejection reactions were recorded; simulation of respiratory disease therapy on Papio hamadryas proved to be an adequate model.

Modern outlook on morphological criteria of organ and tissue decellularization

A rapidly growing development of tissue engineering promotes the increasing interest in the obtainment of variousxa0decellularizedtissues and organs. Minimal quality evaluation criteria of obtained tissue engineered constructionsxa0have been previously specified. In the discussionpaper the group of authors considers the morphologicalxa0methods of matrix evaluation applied by various researchers on the model of heart decellularization. The analysisxa0of modern literature and the authors’ own researches have shown that morphological evaluation of decellularizationxa0quality has to be complex and should consist of several stages which include both basic and additionalxa0evaluation methods.

EPR spectroscopy solutions for assessment of decellularization of intrathoracic organs and tissues.

Using EPR spectroscopy it was established that the determination of the concentration of paramagnetic centers in lyophilized tissues allows indirect evaluation of the quality of decellularization of intrathoracic organs (diaphragm, heart, and lungs), since the content of paramagnetic particles in them can serve as a criterion of cell viability and points to the necessity to repeat decellularization. Experiments in rats showed that the EPR spectra of the native thoracic organs contained paramagnetic centers with g-factor values ranging from 2.007 to 2.011 at a concentration of 10–8 to 6.62 × 10–7 mol/g of lyophilized tissue, whereas in all decellularized tissues of the same organs paramagnetic particles were not detected.