Interaction of Lymphocytes with Mesenchymal Stem Cells

We studied the interaction of neural stem cells and dental pulp-derived mesenchymal stem cells with lymphocytes from autologous and heterologous donors. Flow cytometry analysis with the use of CFSE-labeled lymphocytes demonstrated an increase in the content of proliferating CD8, CD16 and CD56 cells, but not CD4 cells in cultures of HLA-DR-negative mesenchymal stromal cells from the dental pulp co-cultured with lymphocytes. In neural cultures expressing HLA-DR, all subpopulations of T cells and NK cells were activated. No differences between the autologous and heterologous cultures were revealed.

Comparative Analysis of the Proliferative Potential of Human Mesenchymal Stromal Cells from Extraembryonic Organs, Endometrium, and Adipose Tissue

Proliferative activity of mesenchymal stromal cells isolated from five sources (chorionic villi, Wharton's jelly, amnion, endometrium, and adipose tissue) was compared by flow cytometry and real-time PCR (by the content of mRNA of genes encoding of cell cycle regulators). Mesenchymal stromal cells derived from the endometrium demonstrated maximum stability and high proliferative potential.

Characteristics of Multipotent Mesenchymal Stromal Cells from Human Terminal Placenta

Cell cultures isolated by the enzymatic method from the terminal placenta amnion consist mainly from epithelial cells, expressing cytokeratin-7, CD90, and CD73, are characterized by high viability and low proliferative potential. Adhesive cultures of umbilical (Wharton's jelly) cells, despite the fibroblast-like shape of the cells and expression of surface markers, intrinsic to mesenchymal stromal cells, are also characterized by high heterogeneity during the initial stages of culturing, judging by an appreciable share of cytokeratin-expressing cells. The terminal placenta chorionic villi can be a source of cells with the most typical morphology and immunophenotypical profile of the resident multipotent mesenchymal stromal cells, which retain high viability in vitro and have a high proliferative potential.

Profiles of mRNA expression for genes involved in implantation, early and middle phases of secretion stage in human endometrium

The expression of mRNA of 36 genes involved in implantation was studied by reverse transcription and real-time PCR. Significant differences in mRNA expression during the early and middle stages of the secretion phase were detected for genes mmp7, vegf, il2m, il1β, il8, il18, tnfα, il10, tgfβ, igfbp2, etc.

Expression of immunomodulator gene mRNA in co-culture of mesenchymal stromal cells from the placenta and human mononuclear blood cells

The expression of mRNA of cytokines and immunoregulatory molecules characterizing the interaction of mesenchymal stromal cells from chorionic villi of postpartum placenta and allogenic mononuclear blood cells was studied during 3-day co-culturing of these cells. The expression of foxp3, il2ra, and il10 mRNA in floating mononuclear cells increased from day 1 to 3 in co-culture, which can refl ect the process of induction of regulatory T cells in the lymphocyte population under the action of mesenchymal stromal cells.

[A method of quantitative assessment of cytokine gene mRNA expression levels using real-time PCR in homogenous low cell number populations]

We propose a method of quantitative functional activity assessment in cells isolated via sorting on a flow cytometer. We show that cell populations vary in the mRNA expression of cytokine genes immediately after isolation and sorting, while the maintenance of homogenous populations in culture without stimulation results in an increase in these gene mRNA expression. Using the original system, it is now possible to detect mRNA cytokine genes with high sensitivity, starting from 90 cells per specimen. This approach permits genetic and immunogenetic analysis of gene expression with the goal of determining their functions in the in vitro studies.

[Polymorphism of KPI-A genes from plants of the subgenus Potatoe (sect. Petota, Estolonifera and Lycopersicum) and subgenus Solanum]

Kunitz-type proteinase inhibitor proteins of group A (KPI-A) are involved in the protection of potato plants from pathogens and pests. Although sequences of large number of the KPI-A genes from different species of cultivated potato (Solanum tuberosum subsp. tuberosum) and a few genes from tomato (Solanum lycopersicum) are known to date, information about the allelic diversity of these genes in other species of the genus Solanum is lacking. In our work, the consensus sequences of the KPI-A genes were established in two species of subgenus Potatoe sect. Petota (Solanum tuberosum subsp. andigenum--5 genes and Solanum stoloniferum--2 genes) and in the subgenus Solanum (Solanum nigrum--5 genes) by amplification, cloning, sequencing and subsequent analysis. The determined sequences of KPI-A genes were 97-100% identical to known sequences of the cultivated potato of sect. Petota (cultivated potato Solanum tuberosum subsp. tuberosum) and sect. Etuberosum (S. palustre). The interspecific variability of these genes did not exceed the intraspecific variability for all studied species except Solanum lycopersicum. The distribution of highly variable and conserved sequences in the mature protein-encoding regions was uniform for all investigated KPI-A genes. However, our attempts to amplify the homologous genes using the same primers and the genomes of Solanum dulcamarum, Solanum lycopersicum and Mandragora officinarum resulted in no product formation. Phylogenetic analysis of KPI-A diversity showed that the sequences of the S. lycopersicum form independent cluster, whereas KPI-A of S. nigrum and species of sect. Etuberosum and sect. Petota are closely related and do not form species-specific subclasters. Although Solanum nigrum is resistant to all known races of economically one of the most important diseases of solanaceous plants oomycete Phytophthora infestans aminoacid sequences encoding by KPI-A genes from its genome have nearly or absolutely no differences to the same from genomes of cultivated potatoes involved by P. infestans.

[Microbial communities of ancient seeds derived from permanently frozen Pleistocene deposits]

Microbial communities from the surface of ancient seeds of higher plants and embedding frozen material dated to the late Pleistocene (formed about 30 thousand years ago) were studied by various methods: scanning electron microscopy, epifluorescence microscopy, and inoculation of nutrient media, followed by identification of isolated cultures. Both prokaryotic and eukaryotic microorganisms were found on the surface of ancient seeds. The total quantity of bacterial cells determined by direct counting and dilution plating (CFU) for the samples of ancient seeds exceeded the value in the embedding frozen material by one to two orders of magnitude. This pattern was not maintained for mycelial fungi; their quantity in the embedding material was also rather high. A significant difference was revealed between the microbial communities of ancient seeds and embedding frozen material. These findings suggest that ancient plant seeds are a particular ecological niche for microorganisms existing in permafrost and require individual detailed study.