Histone proteins are promising carriers for delivery of recombinant nucleic acids in various cell cultures. Conjugates of proteins with fluorescent dyes are modern tools in the study of cellular transport and intracellular distribution of important biopolymers. The aim of this work was to optimize the method of recombinant histone H1.3 conjugation with photoactivatable fluorescent dye. Also we studied intracellular penetration and subcellular localization of the resulting conjugate. Resulting conjugate was capable of intensive fluorescence in the red region of the spectrum after irradiation with violet light. The degree of conjugation was determined under different reaction conditions. A comparison of the cytotoxicity of histone H1.3 and its conjugate with photoactivated fluorescent dye in HeLa cells and its intracellular localization was characterized. We found that conjugates mainly localize in recycling endosomes and to a lesser extent in peroxisomes. Thus, the resulting conjugate of recombinant histone H1.3 with photoactivatable fluorescent dye can be used for further studies its anticancer activity and as carrier for drugs and nucleic acids delivery into human and animal cells.

There is an ongoing search for new drugs for the treatment of adenovirus infections. In our work the antiviral properties of the recombinant histone H1.3 in in vitro cell culture was investigated and for the first time we demonstrated that recombinant histone H1.3 significantly reduces the efficiency of adenoviral transduction. Also, recombinant histone H1.3 exerts an inhibitory effect on plaque formation on HEK-293A cells monolayer, infected with adenovirus serotype 5, which confirms antiviral properties of histone H1.3 towards adenoviruses.

Ne of the reasons for the failure of potential anticancer drugs in clinical trials is the imperfection of existing preclinical screening systems. Perhaps the most important step is in vitro testing during which several substances with certain properties should be selected from a large number of substances. An effective system of screening should closely resemble the organization of naturally occurring tumors. Cell cultures are the most simple from technical point of view in vitro models of tumors. However, in many respects cell cultures different from natural tumors. Several models which are more accurately (compared to simple monolayer cultures) emulate the tumor and its microenvironment are developed. An example is three-dimensional cultures. Furthermore, additional methods of anticancer drugs testing are developed based on tissue slice cultures. This review describes current in vitro models which can be used to test the activity of potential drugs for use in treating of oncological diseases.

Dysferlinopathies belong to neuromuscular diseases associated with aberrant expression and/or function of dysferlin protein in skeletal muscle, which is caused by mutations in the dysf (dystrophy-associated fer-1-like, DYSF) gene. Because of the large size of the codon-optimized dysf coding region (6243 bp), adenoviral vectors are suitable for the creation of genetic constructs, which are capable of delivering a large amount of recombinant genetic information into both dividing and non-dividing cells, as well as provide a high level of transgene expression. We generated a recombinant adenovirus serotype 5 encoding a codon-optimized gene for human dysferlin (Ad5Dysf) and analysed recombinant protein expression in vitro in HEK-293T cell line.

Human stem cells secretome is currently a very hot area of research. We report that multipotent mesenchymal stromal cells isolated from human third molar dental follicles (MMSCTMDF), are able to secrete high levels of vascular endothelial growth factor (VEGF) when cultured in vitro. Due to the fact that VEGF is a well known angiogenic and neuroprotective factor, the use of MMSC-TMDF is promising for the development of stem cell therapy of various degenerative human diseases.

Lentiviral vectors are widely used in genetic modification of human and animal cells (lentiviral transduction) to enhance their therapeutic potential by expression of recombinant protective and trophic factors. Genetic modification of cells in vitro or ex vivo achieves the specificity of viral transduction, as modified are just cells that have been manipulated in the laboratory. In addition, the introduction of genetically modified cells, but not pure virus, helps to avoid introduction of viral particles into the body of the recipient. This approach allows us to control the expression of therapeutic genes, the immunogenicity of viral vectors and viral transduction. To date, different approaches are used to improve the lentiviral transduction (polycations, protamine sulfate, etc.), but these methods suffer from limited efficacy or high toxicity. For the first time we demonstrated that the recombinant histone N1.3 increases the efficiency of lentiviral transduction by more than 2 times and has no toxic effect on target cells in a wide range of concentrations studied.