In an earlier Phase 1/2 clinical trial using the Edmonton Protocol of steroid free immunosuppression, investigators at University of Illinois at Chicago (UIC) demonstrated the safety of islet preparation, iset transplantation, and medical treatment at UIC. Therefore, the primary purpose of the present Phase 3 clinical trial is to demonstrate the safety and efficacy of allogeneic islet transplantation in improving glycemic control in Type 1 diabetic patients using the UIC protocol that was developed and proven effective during the Phase 1/2 clinical trial.