The development of MCS-based therapies for autoimmune diseases, including T1D, is a new field with a lot of promise, but also a lot of uncertainty. While successful treatment of disease allogeneic MSCs has been achieved, some MSC treatment failure has also been reported. The significance of this proposal is that it will fill a significant gap in the current understanding of mechanisms associated with human MSC-based therapies for T1D. These studies raise critical issues such as which patients could benefit from MSC treatment and when autologous or heterologous MSCs are best to be utilized. Here we propose to investigate whether T1D-derived MSCs are as effective in suppressing inflammation as non-T1D derived MSCs. Importantly, we are proposing to evaluate this using human samples as there is murine data to suggest that T1D-derived MSCs are genetically altered which affect their efficacy as immunosuppressive therapies.