The article briefly presents the main results of the program committee of the VI National Congress on Regenerative Medicine and highlights the most priority areas for the formation of the scientific program of the future event. The message of the editor-in-chief and president of the Society for Regenerative Medicine — Academician V.A. Tkachuk is an invitation for leading specialists in the field of regenerative medicine to participate in the Congress.

Cellular immunotherapy CAR-T (Chimeric Antigen Receptor T-Cell, or T-cells with a chimeric antigen receptor) is an advanced approach to the treatment of oncological diseases. Currently, CAR-Ttherapy has shown high efficiency in the treatment of oncohematological diseases. At the same time, numerous attempts to create CAR-T-constructs for the treatment of solid tumors, in particular breast cancer (BC), have not demonstrated significant clinical efficacy. It is assumed that the key to solving these problems lies in the development and implementation of new genetic engineering strategies.
The purpose of this review was to summarize and systematize existing studies with CAR technology. In this paper, we summarize potential targets for the treatment of BC, detail the existing limitations of using these technologies and identify important future trends in this area.

The study of molecular mechanisms of regeneration requires convenient models for in vitro and in vivo studies. In vitro cell cultures can fulfill such a function. However, their rapid aging and loss of initial specific properties in culture is a significant limitation of their use. Telomerase expression can help to overcome these limitations: it can prolong proliferative activity and stabilize the initial properties of a primary cell culture. Here, we created and studied the properties of human adipose tissue multipotent mesenchymal stromal cell (MSC) cultures that overexpress the catalytic protein subunit of human telomerase ( hTERT). We found that these MSC cultures were able to proliferate up to 38–63 PD, kept sensitivity to noradrenaline, serotonin, glutamate, γ-aminobutyric acid, parathyroid hormone, angiotensin II and histamine until at least 26 PD, retained MSC-specific immunophenotype until at least 36 PD, and preserved the ability to adipogenic, osteogenic and chondrogenic differentiation until at least 39 PD. Moreover, overexpression of hTERT in MSC cultures stabilized the qualitative and quantitative composition of their secretome at long-term passaging (at least up to 30 PD). The obtained results allow us to consider telomerase hyperexpression as a promising approach to obtaining MSC cultures with prolonged proliferative activity, which can be used as a stable and convenient object for fundamental and applied studies in the field of regenerative medicine.

The choice of cell culturing conditions is a limiting factor for the procedures of obtaining and expanding cells in vitro, as well as for developing drugs based on them. In this work, we analyzed the characteristics of primary human mesenchymal stromal cell (MSC) lines obtained from adipose tissue, isolated and cultured in a growth medium supplemented with AdvanceSTEM™ serum (Cytiva) and a serum-free medium CellCor™ Serum free CDM for hMSC (Xcell). The use of two types of media made it possible to obtain viable MSC cell lines from human adipose tissue. At the same time, the proliferation rate in the serum-free medium was higher, which was expressed in shortening of PDT, lag phase, time between passages, both during cultivation of freshly isolated cells and after defrosting of lines initially cultured in a medium with serum. However, the use of a standard cryopreservation protocol for cells isolated and cultured in CellCor™ medium did not allow for the effective recovery of these lines from thawing. In addition, a tendency for MSCs to form clusters was found when using this medium, indicating the need for further selection of working conditions with it. MSCs are among the most promising cells for the development of products for regenerative medicine, in particular, due to the proteins secreted by these cells. The concentrations of growth factors VEGF, IGF, HGF and angiopoietin-1 in the cell-conditioned growth medium did not differ significantly when cultured in the two media. Also, no statistically significant differences were found in the concentration and size of extracellular vesicles in the medium. Thus, the use of the serum-free CellCor™ medium allows for the elimination of xenogenic products and can reduce the time of MSC cell mass production, which is an important parameter in the development of cell products, without changing the secretory properties of these cells compared to cultivation in the AdvanceSTEM™ medium, however, further selection of conditions is required to optimize the protocols.

The 20th century marked the understanding that more than 80% of genes have an additional biological function in the cell associated with the regulation of the expression of other genes. Non-coding sequential-type RNA regulators, including microRNAs, capable of changing the expression of proteins in the cell, can be expressed with such genes. MicroRNAs are singlestranded RNA sequences 20–25 nucleotides in length that regulate gene expression at the posttranscriptional level through degradation or repression of mRNA translation. This review examines aspects of the biogenesis of microRNAs in mammalian cells, as well as their functions in endothelial cells and in the regulation of angiogenesis.