Allogenic Use of Human Placenta-Derived Stromal Cells as a Highly Active Subtype of Mesenchymal Stromal Cells for Cell-Based Therapies.

The application of mesenchymal stromal cells (MSCs) from different sources, including bone marrow (BM, bmMSCs), adipose tissue (atMSCs), and human term placenta (hPSCs) has been proposed for various clinical purposes. Accumulated evidence suggests that the activity of the different MSCs is indirect and associated with paracrine release of pro-regenerative and anti-inflammatory factors. A major limitation of bmMSCs-based treatment for autologous application is the limited yield of cells harvested from BM and the invasiveness of the procedure. Similar effects of autologous and allogeneic MSCs isolated from various other tissues were reported. The easily available fresh human placenta seems to represent a preferred source for harvesting abundant numbers of human hPSCs for allogenic use. Cells derived from the neonate tissues of the placenta (f-hPSC) can undergo extended expansion with a low risk of senescence. The low expression of HLA class I and II on f-hPSCs reduces the risk of rejection in allogeneic or xenogeneic applications in normal immunocompetent hosts. The main advantage of hPSCs-based therapies seems to lie in the secretion of a wide range of pro-regenerative and anti-inflammatory factors. This renders hPSCs as a very competent cell for therapy in humans or animal models. This review summarizes the therapeutic potential of allogeneic applications of f-hPSCs, with reference to their indirect pro-regenerative and anti-inflammatory effects and discusses clinical feasibility studies.

CD90 Is Dispensable for White and Beige/Brown Adipocyte Differentiation.

Brown adipose tissue (BAT) is a thermogenic organ in rodents and humans. In mice, the transplantation of BAT has been successfully used to combat obesity and its comorbidities. While such beneficial properties of BAT are now evident, the developmental and cellular origins of brown, beige, and white adipocytes have remained only poorly understood, especially in humans. We recently discovered that CD90 is highly expressed in stromal cells isolated from human white adipose tissue (WAT) compared to BAT. Here, we studied whether CD90 interferes with brown or white adipogenesis or white adipocyte beiging. We applied flow cytometric sorting of human adipose tissue stromal cells (ASCs), a CRISPR/Cas9 knockout strategy in the human Simpson-Golabi-Behmel syndrome (SGBS) adipocyte model system, as well as a siRNA approach in human approaches supports the hypothesis that CD90 affects brown or white adipogenesis or white adipocyte beiging in humans. Taken together, our findings call the conclusions drawn from previous studies, which claimed a central role of CD90 in adipocyte differentiation, into question.

Differential effects of adipose tissue stromal cells on the apoptosis, growth and invasion of bladder urothelial carcinoma between the superficial and invasive types.

OBJECTIVES: To clarify the interaction between adipose tissue stromal cells and bladder cancer cells. METHODS: Superficial (RT4) and invasive (EJ) urothelial carcinoma cells were cultured on adipose tissue stromal cell-embedded or non-embedded collagen gel. Cells were analyzed by immunohistochemistry, western blot and real-time reverse transcription polymerase chain reaction. RESULTS: Adipose tissue stromal cells inhibited growth of RT4, while they promoted the apoptosis. In contrast, adipose tissue stromal cells promoted growth of EJ, but they did not affect the apoptosis. Adipose tissue stromal cells slightly promoted expression of mitogen-activated protein kinase cascade in RT4 and EJ. Adipose tissue stromal cells promoted display of the molecular-targeted agent human epidermal growth factor receptor-2 in only RT4. In turn, RT4 and EJ enhanced α-smooth muscle actin (myofibroblast marker) and S-100 protein (adipocyte marker) expression of adipose tissue stromal cells, respectively. CONCLUSIONS: These findings suggest that: (i) adipose tissue stromal cells might suppress the progression of superficial-type cancer, whereas they might promote that of invasive type; (ii) adipose tissue stromal cell-activated mitogen-activated protein kinase pathway might play differential roles in both types of bladder cancer; (iii) human epidermal growth factor receptor-2 could represent a critical therapeutic agent for the superficial type under adipose tissue stromal cells-cancer interaction; and (iv) superficial bladder cancer might promote myofibroblast differentiation of adipose tissue stromal cells as a cancer-associate phenotype, whereas invasive bladder cancer might promote their adipocyte differentiation.