[Self-regulated closed-loop therapy of diabetes]

The development of an artificial pancreas, a system in which insulin delivery would be regulated continuously by concomitant glucose levels, has been for a long time considered as a dream by diabetologists and diabetic patients. Two approaches are possible. The first one, electromechanical, consists of a glucose sensor, a computer and an insulin pump. Its development may be hindered by the inadequate biocompatibility of the glucose sensor. This led to consider at first the use of a disposable glucose sensor as part of a continuous glucose monitoring system. The second approach aims at developing a bioartificial pancreas, in which isolated islets of Langerhans would be protected against immune rejection by an artificial membrane permeable to glucose and insulin but not so to factors responsible for immune rejection. Thus, it may become possible to transplant a large number of patients before the onset of diabetic complications with xenogeneic islets, without need for any immunosuppression. Promises and obstacles of these two approaches are described herein.