The results of a clinical phase 1/2 open trial conducted at the Jinan Military General Hospital in China were published in the latest issue of BMC Medicine. 15 patients with type 1 diabetes were enrolled in the study, with an average age of 29 years (from 15 to 41 years) and an average medical history of 8 years (from a minimum of 1 year to a maximum of 21 years). Divided into two groups, one group underwent stem cell culture therapy, in which lymphocytes (i.e., immune cells in the body) from the patient’s blood were isolated through a closed-loop system, incubated for 2-3 hours along with umbilical cord blood stem cells, and subsequently transfused back into the patient. Six of the diabetic patients (group A) still had some islet function and were relatively mild, while the other six (group B) lost their islet function completely. Another group of 3 patients served as a control group. The results showed that this umbilical cord blood stem cell cultivation treatment significantly restored the function of the islets, and their endogenous insulin levels increased significantly, with C-peptide levels increasing by an average of 0.42 ng/ml in group A and 0.21 ng/ml in group B, while the control group decreased by 0.08 ng/ml. In addition, the problem was also reflected by the daily insulin doses used by the patients. In group A, the insulin dose was reduced from 36 U per day to 22 U at 12 weeks postoperatively, a 38% reduction, and in group B, the insulin dose was reduced from 48 U per day to 36 U per day, a 25% reduction. In contrast, the insulin dose was not changed in the control group. The glycosylated hemoglobin in group A decreased from 8.73% to 7.67% at 4 weeks postoperatively and then to 6.82% at 12 weeks postoperatively, while in group B it decreased by 1.68% at 12 weeks postoperatively compared to the preoperative level. The control group, on the other hand, showed no significant difference in change, from 9.0% originally to 8.7% at 12 weeks. It is promising that the own islet function recovered better functionally with time, as shown by the continuous increase of C-peptide level. In addition, immune function improved in type 1 diabetic patients cultured with umbilical cord blood stem cells, as evidenced by increased expression of co-stimulatory factors (CD28 and ICDS), increased number of CD4+CD25+FoxP3+ Tregs cells, and reestablishment of the Th1/Th2/Th3 cytokine balance.