INS and type 1 diabetes mellitus: They suggested three possible explanations which are that T1DM patients are very lean and do not have much adipose, only a small amount of lipoaspirate is collected from them, and the implanted ICAs may not survive for long due to autoimmune attack, so to protect implanted ICAs, they recommended allogenic ICAs derived from MSCs and a biocompatible cell impermeable scaffold but in the case of type 2 diabetes, the results are more impressive due to increased insulin secretion from ICAs.