Effect of different cryopreservation regimens on Ehrlich carcinoma growth.

The freezing rate is a decisive factor in determining the purpose of using low temperatures, i.e., for cryoablation or cryobanking of tumor cells. The research aim was to determine effect of different cryopreservation regimens on Ehrlich carcinoma (EC) growth in vivo and subpopulation composition of the formed ascites. The previously cryopreserved with slow and rapid rates EC cells were cultured in peritoneal cavity (PC) of mice for 7 days. Absolute number of cells in the PC, the subpopulation composition of tumor with flow cytometry using CD44 and CD24 markers were determined. Immediately after warming, a significant redistribution of EC subpopulation composition with a decreased content of the most tumorigenic CD44high cells after both freezing regimens was found. Culturing in vivo for 7 days contributed to the restoration of EC subpopulation composition, but with some a decrease in the tumor growth intensity when slow cooling was used. Rapid cooling contributed to significant inhibition of tumor growth with a reduced number of CD44+ and increased CD24+ cells. None of the cryopreservation regimens resulted in a complete elimination of tumorigenic CD44high tumor cells. The freezing rate determines the preservation of the subpopulation composition of the EC and intensity of its growth in vivo.

Experimental therapy of graft-versus-host disease by mesenchymal stromal cells grown on oxide nanocoatings.

Immune aggression to transplanted allogeneic bone marrow, i.e. the graft-versus-host disease (GVHD), could be decreased by the suppression of effector and/or activation of T- regulatory cells (Treg). This task could be solved by co-transplantaiton of allogeneic bone marrow and mesenchymal stromal cells (MSCs). This study demonstrated the elevated immune modulating activity of MSCs by their culturing in vitro on Al203 oxide nanocoatings. Introduction of the cells to the animals with GVHD resulted in an increased content of Treg in the spleen of bone marrow recipients, reduced severity of the pathology, and higher survival of animals. Thefindings could be the basis for developing the new approaches to optimize the GVHD treatment methods involving the oxide nanocoating cultured MSCs.

[FUNCTIONAL ACTIVITY OF EHRLICH CARCINOMA CELLS AFTER TREATMENT WITH HYBRID NANOCOMPLEXES CONTAINING ORTHOVANADATES OF RARE-EARTH ELEMENTS, CHOLESTEROL AND LUMINESCENT DYE].

Tumor development is the consequence of expanding the population of low differentiated cells with unlimited self-maintenance potential, i.e. cancer stem cells (CSCs). Application of new forms of nanocomposites capable of binding to CSCs and inducing the tumor destruction is perspective direction for treating this pathology. There have been developed the methods of obtaining hybrid nanocomplexes containing rare-earth orthovanadates GdYVO4:Eu³âº, cholesterol and luminescent dye Dil. By immune fluorescence method using monoclonal antibodies to CD44, CD24, CD117 and Sca-1 markers there has been established the change in the ratio of tumor progenitors of various differentiation levels in a general pool of Ehrlich carcinoma (EC) after treatment with hybrid nanocomplexes. Essential reduction in the concentration of the most tumorogenic CD44high cells with simultaneous rise in the number of CD117⁺-cells resulted in an increased index of CD44high/CD117⁺ ratio. It has been demonstrated that application of hybrid nanocomplexes suppressed the tumor growth almost by 80%. The value of cooperative interactions of the cells with different phenotype signs in tumor sites has been proved. The index of CD44high/CD117⁺ ratio can be used as one of diagnostic and prognostic parameters of development and inactivation rate of tumor process when using different types of anti-tumor therapy.

The use of nanocomposite coatings with various physicochemical properties in tissue engineering.

We studied the effect of nanocomposite coatings with various physicochemical properties on the structural and functional properties (adhesion potential, phenotype, gene expression) of mesenchymal stem cells. Of all tested nanocoatings (Al2O3, ZrO2, Ta2O5), oxide coating Al2O3 enriched in vitro monolayer bone marrow cell culture with cells carrying mesenchymal stem cells phenotype markers and stimulated expression of ido gene, which can confer new therapeutic potencies to these cells and extend their application in clinical practice.

[Strain-dependent disruption of the functional activity of bone marrow stromal cells from mice infected with influenza A]. / Shtammozavisimoe narushenie funktsional'noi aktivnosti kletok stromy kostnogo mozga myshei, zarazhennykh virusom grippa A.

Infection of mice with influenza A virus disturbs the proliferative activity of bone marrow stromal fibroblasts involved in regulation of bone marrow hemopoiesis. Myelosuppression induced by influenza A virus can be a result of dysfunction of bone marrow stromal tissue. Disorders in multiplication of bone marrow fibroblasts induced by influenza virus are strain-dependent.

[Conservation of bone marrow CFUc in different phases of the cell cycle during cryopreservation]. / Sokhrannost' kostnomozgovykh KOEc, nakhodiashchikhsia v raznykh fazakh kletochnogo tsikla, pri kriokonservatsii.

The effect of low temperature (-196 degrees C) preservation on the recovery of colon-forming units (CFUs) of bone marrow at different phases of the cell cycle before cryopreservation is dealt with. The intact bone marrow "enriched" with CFUs in S phase of the cell cycle and the bone marrow without colony-forming units in S phase were exposed to cryopreservation. After cryopreservation of the bone marrow enriched with CFUs in S phase and th bone marrow without colony-forming units in S phase the number of CFUs decreases by the same value as in the cryopreserved bone marrow obtained from intact mice.