Accumulated clinical experience indicates that there is an inverse association between beta-cell function and chronic complications of type 1 diabetes mellitus (DM)—the higher the C-peptide levels (an indirect measure of viable beta-cell function), the lower the incidence of microvascular complications of type 1 DM.1 Since the establishment of the autoimmune etiology of type 1 DM in the late 1970s, many clinical trials analyzing the effects of different types of immune interventions demonstrated that beta-cell preservation is an achievable target in different degrees.2,3
Based on the theory of possible reconstitution of immune tolerance after "immunologic reset" with autologous nonmyeloablative hematopoietic stem cell transplantation (HSCT),4 in 2007, we reported a phase 1/2 trial evaluating the safety and metabolic effects of autologous nonmyeloablative HSCT in 15 patients with newly diagnosed type 1 DM.5 The majority of patients became insulin free with no further immune suppressive medications. However, it was suggested that subsequent insulin independence was a prolonged honeymoon period due to dietary and exercise changes associated with close posttransplant medical observation.6,7
Herein, we report updated results of the extended group of 23 patients transplanted from January 2004 through April 2008, followed up from 7 to 58 months (mean, 29.8 months and median, 30 months) after treatment, and monitored for C-peptide levels to determine if posttransplant insulin independence was due to improved endogenous beta-cell function independent of dietary or lifestyle alterations.
Diabetes type 1 cord blood treatment_clinical trial.pdf