Mesenchymal Stem Cells from the Deciduous Tooth Pulp Lose their Ability to Suppress the Differentiation of Dendritic Cells during Long-Term Culturing.

A culture of cells expressing markers of mesenchymal stem cells (MSC) (CD73, CD90, CD44, CD29, and CD49b), but not hematopoietic cell markers, and capable of multilineage differentiation was isolated from the deciduous tooth pulp. Co-culturing with immature dendritic cells in the presence of LPS did not reveal an ability of the MSC to suppress the maturation of dendritic cells. On the contrary, co-culturing of MSC with monocytes in the presence of granulocyte-macrophage CSF and IL-4 led to complete suppression of monocyte differentiation into dendritic cells. However, long-term culturing of MSC from dental pulp showed that by the passage 11, they almost completely lose their suppressor ability. These results indicate that the immunological properties of MSC can change during culturing without changing their phenotypic markers. This should be taken into account when creating biomedical cell products.

Colorectal Cancer and Tumor Stromal Cells Have Different Effects on the Differentiation and Maturation of Dendritic Cells In Vitro.

We compared the ability of SW837, SW480, HT-29, Caco-2, and HCT116 colorectal cancer lines and cancer-associated fibroblasts obtained from a colorectal adenocarcinoma biopsy specimen to modulate differentiation and maturation of dendritic cells in co-culture. The expression of surface markers of dendritic cell differentiation (CD1a) and maturation (CD83), as well as the expression of CD14 monocyte marker was evaluated by flow cytometry. Cancer-associated fibroblasts completely suppressed dendritic cell differentiation from peripheral blood monocytes induced by granulocyte-macrophage CSF and IL-4, but had no significant effect on their maturation under the influence of bacterial LPS. On the contrary, tumor cell lines did not interfere with monocyte differentiation, although some of them significantly reduced the level of CD1a expression. In contrast to cancer-associated fibroblasts, tumor cell lines and conditioned medium from primary tumor cell culture suppressed LPS-induced maturation of dendritic cells. These results suggest that tumor cells and cancer-associated fibroblasts can modulate different stages of the antitumor immune response.

[Comparison of the expression profile of surface molecular markers on mesenchymal stromal cell cultures isolated from human endometrium and umbilical cord]. / Sravnenie profilia ékspressii poverkhnostnykh molekuliarnykh markerov na mezenkhimnykh stromal'nykh kletkakh kul'tur, poluchennykh iz éndometriia i pupoviny cheloveka.

Endometrial mesenchymal stromal cells (eMSCs), along with mesenchymal stromal cells (MSCs) isolated from other tissues, are promising for use in regenerative medicine. The benefits of eMSCs include their presence in adults, simplicity of isolation, high proliferative and differentiation capacity. In this study, we have employed the flow cytometry technique to assess expression of 28 molecular markers on the surface of two eMSCs cultures. The culture of MSCs isolated from Wharton's jelly of the umbilical cord (uMSCs) was used as a reference, because uMSCs were studied in details earlier and demonstrated their effectiveness in vivo. Both types of MSCs demonstrated similar expression profiles. They included stem cells surface molecules, cell adhesion molecules and their ligands, some receptor molecules responsible for cell metabolism and proliferation, as well as immunological response molecules.