The last few decades, an intense interest has been developed in using regulatory
T cells (Tregs) for immunotherapy by the biomedical community, depending on
the facts that Tregs can modulate both innate and adaptive immunity. Recently,
the therapeutic potential of Tregs has been moved to clinical practices in the
field of autoimmune diseases and after allogeneic transplantation. Many clinical
trials have involved Treg adoptive transfer to treat autoimmune diseases, solid
organ transplantation, and hematopoietic stem cell transplantation (HSCT). The
researchers have designed many strategies to isolate, preserve, expand, and
infuse Tregs. However, the sources of Tregs cells remain one of many obstacles
hindering Treg clinical applications. Here, we review current approaches have
being explored for Treg expansion and the possible sources including induced
pluripotent stem cells (iPSCs) in the perspective of clinical therapeutic protocols