Regenerative Potential of a Suspension and Spheroids of Multipotent Mesenchymal Stromal Cells from Human Umbilical Cord on the Model of Myocardial Infarction in Rats

Regenerative potential of multipotent mesenchymal stromal cells from the human umbilical cord (MMSC-UC) in the suspension and spheroid form was revealed during the progression of experimental small focal myocardial infarction in rats. In isoproterenol-induced myocardial infarction, foci of necrosis and inflammatory infiltrate and at later terms fibrosis foci were found mainly in the left ventricle of rat heart. In rats receiving MMSC-UC, destructive changes in the myocardium, fibrous scars, and inflammatory process were less pronounced. MMSC-UC also contributed to normalization of the morphofunctional parameters of the heart. Spheroids exhibited higher efficiency in comparison with cell suspension.

Influence of Fucoxanthin on Proliferative Activity of Human Melanocyte Culture

We studied the effect of algae pigment fucoxanthin on proliferative activity of melanocyte culture from human skin. Fucoxanthin in high concentrations can be cytotoxic, which was confirmed by changes in melanocyte morphology and a decrease in their proliferative activity.

Induction of Vasculo- and Osteogenesis in Spheroids Formed by Adipose-Derived Stromal Cells

Vascularization of bioengineered bone tissue constructs remains a challenging problem of regenerative medicine. Spheroids generated in 3D culture of adipose-derived stromal cells supplemented with inducing factors demonstrate stable characteristics and express of mesenchymal, endothelial, and osteoblasts markers, and represent a prototype of vascularized microtissue. Adipose-derived stromal cells spheroids induced to both angio- and osteogenic differentiation can be used in development of new innovative technologies for in vitro fabrication of vascularized bioequivalents for repair of large bone defects.

2D/3D buccal epithelial cell self-assembling as a tool for cell phenotype maintenance and fabrication of multilayered epithelial linings in vitro

Maintaining the epithelial status of cells in vitro and fabrication of a multilayered epithelial lining is one of the key problems in the therapy using cell technologies. When cultured in a monolayer, epithelial cells change their phenotype from epithelial to epithelial-mesenchymal or mesenchymal that makes it difficult to obtain a sufficient number of cells in a 2D culture and to use them in tissue engineering. Here, using buccal epithelial cells from the oral mucosa, we developed a novel approach to recover and maintain the stable cell phenotype and form a multilayered epithelial lining in vitro via the 2D/3D cell self-assembling. Transitioning the cells from the monolayer to non-adhesive 3D culture conditions led to formation of self-assembling spheroids, with restoration of their epithelial characteristics after epithelial-mesenchymal transition. In 7 days, the cells within spheroids restored the apical-basal polarity, and the formation of both tight (ZO1) and adherent (E-cadherin) intercellular junctions was shown. Thus, culturing buccal epithelial cells in a 3D system allowed us to recover and durably maintain the morphological and functional characteristics of epithelial cells. The multilayered epithelial lining formation was achieved after placing spheroids for 7 days onto a hybrid matrix, which consisted of collagen layers and reinforcing poly (lactide-co-glycolide) fibers and was proven promising for replacement of the urothelium. Thus, we offer an effective technique of forming multilayered epithelial linings on carrier-matrices using cell spheroids that was not previously described elsewhere and can find a wide range of applications in tissue engineering, replacement surgery, and regenerative medicine.

[Cellular Model Based on Laser Microsurgery of Cell Spheroids to Study the Repair Process]

In this study, modern techniques of laser microsurgery of cell spheroids have been used to develop a new simple, reproducible model for studying the mechanisms of repair and regeneration in vitro. Nanosecond laser pulses were applied to perform a microdissection of the outer and the inner zones of the spheroids from dermal fibroblasts. To achieve effective dissection and preservation of spheroid viability, the optimal parameters were chosen: 355 nm wavelength, 100 Hz frequency, 2 ns pulse duration, laser pulses in the range of 7–9 μ J. After microdissection, we observed injury of the spheroids : the edges of the wound surface opened and the angular opening reached a value of more than 180°. As early as during the first hour after spheroid microdissection with laser radiation, the surviving cells changed their shape: cells on the spheroid surface and directly in the damaged area became rounded. One day after microdissection, the structure of the spheroids began to partially recover, the cells in the surface layers began to take the original flattened shape; debris of dead damaged cells and their fragments was gradually cleared from the spheroid composition. In the proposed model, the first data on stimulation of structure recovery of injured spheroids from dermal fibroblasts with a P199 synthetic polypeptide, which is used in cosmetology for the initiation of antiaging and regenerative effects in the skin, were received. After microdissection, recovery of the spheroids structure with a few surface layers of flattened imbricated arranged cells and polygonal cells of the inner zone in the presence of P199 peptide was faster than in the control group, and was completed within 7 days, presumably due to the remodeling of the survived cells.

The technology of obtaining multipotent spheroids from limbal mesenchymal stromal cells for reparation of injured eye tissues

It is known that stem and progenitor cells open new possibilities for restoring injured eye tissues. Limbal eye zone, formed mainly by derivatives of neural crest, is the main source of stem cells for regeneration. The current study considers development of innovative technology for obtaining 3D spheroids from L-MMSC. It was shown that under 3D conditions L-MMSC due to compactization and mesenchymal-epithelial transition self-organize into cellular reparative modules. Formed L-MMSC spheroids retain and promote undifferentiated population of stem and progenitor limbal cells, as supported by expression of pluripotency markers - Oct4, Sox2, Nanog. Extracellular matrix synthetized by cells in spheroids allows retaining the functional potential of L-MMSC that are involved in regeneration of both anterior and, probably, posterior eye segment.

Application of the capillary electrophoresis method for the study of plasma proteins homocysteinylation

PURPOSE

Purpose. This article describes the use of capillary electrophoresis with UV detection to determine the ratio of protein-bound homocysteine and cysteine concentrations in human plasma.

METHODS

Plasma samples were reduced with dithiothreitol and derivatized by thiocarbonyldiimidazole before being filtered again for purification of proteins. The pre-concentration of analytes was carried out directly in the capillary (48.5 cm in length and an inner diameter of 50 mkm) by NaOH post-injection. The eletrophoretic separation of analytes was carried out using 0.2 M ammonium acetate with 25 mM hexadecyltrimethylammonium bromide.

RESULTS

Limit of quantitation for homocysteine was 0.8 mkM, reproducible ratio of cysteine/homocysteine <5%, full analysis time 15 min.

CONCLUSION

The ratio of bound cysteine to homocysteine is characterized by the same regularity as the ratio of their total content. It has a fairly high degree of correlation with the level of bound homocysteine and it is characterized by less variability than the level of total homocysteine. This has the advantage of use the bound cysteine/homocysteine ratio for assessing the risk of cardiovascular disease complications.

Pathophysiological and molecular mechanisms of extracellular matrix protein resorption during skin aging, and the ways to their restoration

The article is a short review of the most studied molecular mechanisms leading to skin aging. It considers mechanisms of cellular aging, oxidative stress, development of chronic inflammation, as well as synthesis and degradation of extracellular matrix proteins. The review also contains examples of extracellular matrix restoration using cell and pharmacological technologies.

Laser-based technique for controlled damage of mesenchymal cell spheroids: a first step in studying reparation in vitro

Modern techniques of laser microsurgery of cell spheroids were used to develop a new simple reproducible model for studying repair and regeneration in vitro. Nanosecond laser pulses (wavelength 355 nm, frequency 100 Hz, pulse duration 2 ns) were applied to perform a microdissection of the outer and the inner zones of human bone marrow multipotent mesenchymal stromal cells (BM MMSC) spheroids. To achieve effective dissection and preservation of spheroid viability, the energy of laser pulses was optimized and adjusted in the range 7-9 μJ. After microdissection, the edges of the wound surface opened and the angular opening reached a value of more than 180°. The destruction of the initial spheroid structure was observed in the wound area, with surviving cells changing their shape into a round one. Partial restoration of a spheroid form took place in the first six hours. The complete structure restoration accompanying the reparative processes occurred gradually over seven days due to remodelling of surviving cells.

Summary: The technique of precise nanosecond laser microsurgery of mesenchymal cell spheroids was used to develop a new simple reproducible model for studying repair and regeneration in vitro.

[Dynamics of osteogenesis associated with inoculation of autologous stromal cells from rat adipose tissue (experimental-morphological study)]

Experiment was evaluated on 40 male Wistar rats. On the experimental model of mandible injury, bone autologous graft from tibia was placed on the surface of mandible (host bone). In the main experimental group, consisting of 20 animals, autologous rat adipose-derived stromal cells (ADSCs) were inoculated in space between autograph and host bones. ADSCs were not inoculated in the group of comparison. In experimental group with inoculated cells, the formation of a new fibroreticular bone structures in space between autograph and host bone was observed. These structures further underwent secondary reorganization and differentiation during the process of remodeling. As a result of the conducted study it was shown that in the experimental group by the day 180, statistically significant reduction of the area occupied by an immature fibroreticular bone took place. The reported phenomenon could be explained as a result of decline of the number of active cells in the population of inoculated ADSC, which is in consent with theory of limited cell division number due to telomeres shortening, described by Hayflick L. and Moorhead P.S. (1961).

[Experience of culturing anterior epithelial corneal cells from human eye ball]

Adult corneal epithelium is often exposed to environmental stress, injured and repaired by limbal stem cells. Injury of corneal epithelial layer leads to reduction of visual clarity and loss of vision. Recently it was shown that epithelial layer also contains stem cells. Obtaining cell culture of corneal epithelium will allow understanding mechanisms of cell behavior and differentiation, their metabolism and reaction on environmental stress in health and disease. Moreover, cultured corneal epithelial cells can be considered as a promising material for constructing bioartificial cornea. The aim of this study was to isolate cells of anterior corneal epithelium from human donor cornea and to study their morphological and functional characteristics in vitro. The results of our study showed the possibility of culturing epithelial cells in vitro. The observed changes in cell morphology, their flow growth character as well as active proliferation and up-regulation of mesenchymal markers expression, indicate, in our opinion, epithelial-mesenchymal transition taking place in long-lasting culture of human anterior corneal epithelial cells. The obtained cultures can be used for further studies of pathological processes taking place in cells during drugs testing or controlling the phototoxic effect of different types of emission.