Isolation and Characterization of Novel, Highly Proliferative Human CD34/CD73-Double-Positive Testis-Derived Stem Cells for Cell Therapy

Abstract

Human adult stem cells are a readily available multipotent cell source that can be used in regenerative medicine. Despite many advantages including low tumorigenicity, their rapid senescence and limited plasticity have hampered their use in cell-based therapies. In the present study, we isolated CD34, CD73-double positive 38 testicular stromal cells and found the expression of CD34 was closely related to the cells’ stemness and proliferation. The CD34/CD73 positive cells grew in vitro for an extended period of time, yielding a multitude of cells (5.6x1016cells) without forming any tumors in vivo. They also differentiated into all 3 germ layer lineages both in vivo and in vitro, produced cartilage more efficiently than bone marrow stem cells, and importantly, restored erectile function in a cavernous nerve crush injury rat model. The mean ICP/MAP ratios was significantly lower in the injury group (0.20±0.01) compared to the sham group (0.70±0.02). Periprostatic injection of either BM-MSCs (0.44±0.05) or HTSCs (0.44±0.07)resulted in a significant increase of the ICP/MAP ratio compared with the injury group (P<0.001). In the prostates of treated animals, the human specific antibody and TuJI -double-positive cells in the crush injury area and some CellTracker_ CM-DiI were observed. Thus, these highly proliferative testicular stromal cells may represent a promising new autologous cell source for clinical use