Subject: Can we succesfully control diabetes with encapsulated beta-cells?

I have been recently employed as a chemist on a  project aiming to coat 
pancreatic beta-cells with alginate + poly-lysine coats.  I understand that 
this has been successfully done by others, such as Calafiore's group in 
Italy.  The key word in my question is "succesfully".   Calafiore claims 
the diabetic dogs with the encapsulated beta-cells had normal blood glucose 
levels for 100 days.  So what are the problems?  Haven't they developed a 
successful product?   

Re: Can we succesfully control diabetes with encapsulated beta-cells?