• Stem cell therapies for type 1 diabetes are novel.
• The use of stem cells in the generation of a renewable source of b-cells remains a promising reality.
• A meta-analysis of the clinical efficacy of stem cell therapy for diabetes mellitus revealed the following: (1) remission of diabetes mellitus is possible following stem cell therapy; (2) stem cell transplantation can be a safe and effective approach for therapy of diabetes mellitus; (3) available data indicate that the most promising therapeutic outcome was shown in mobilized marrow CD34+ hematopoietic stem cells (HSCs); (4) patients with previously diagnosed diabetic ketoacidosis are not good candidates for the applied approaches stem cell therapy; (5) stem cell therapy at early stages after diabetes diagnosis is more effective than intervention at later stages; and (6) well-designed large scale randomized studies considering the stem cell type, cell number and infusion method in diabetes patients are urgently needed (El-Badawy A, El-Badri N. PLoS One. 2016;11(4):e0151938).
• Autologous umbilical cord blood transfusion in children with type 1 diabetes is safe but has yet to demonstrate efficacy in preserving C-peptide (Haller MJ, et al. Diabetes Care. 2009;32(11):2041-6).
• A major issue that needs to be addressed is the in vitro maturation of insulin-positive cells.

Even with an abundant supply of stem cell-derived b-cells with robust glucose-responsiveness, many issues still need to be addressed and resolved before this approach becomes a therapeutic option.