Introduction: Glucagon-like peptide-1 (GLP-1) is a physiological incretin hormone from the lower gastrointestinal tract. GLP-1 also lowers glucagon concentrations, slows gastric emptying, stimulates insulin biosynthesis. Therefore, GLP-1 offers some interesting perspective for the treatment of  type 1diabetic patients. One of the potentially effective therapeutic approaches to regenerating islet cells is autologous hematopoietic stem cell transplantation (HSCT).   
Therefore, the dynamics of GLP-1 level in patients with type 1diabetes mellitus (DM) after autologous HSCT is sure to be a scientifically interesting subject.
Materials and Methods: 6 patients (2 female, 4 male) aged from 19 to 35 years old with type 1 DM received the autologous HSCT by intravenous infusion.
Both before and 3 months after the autologous HSCT GLP-1, C-peptide, glycated hemoglobin (HbA1C) levels were analyzed with use of ELISA method in these patients.
Results and Discussion: First, we examined the baseline GLP-1and C-peptide levels in patients with type1 DM, they were low, respectively, they amounted to 0,062+0,022 ng/ml and 0,008+0,003 ng/ml. 3 months after the autologous HSCT the mean GLP-1level increased significantly to 0,107+0,037 ng/ml (p=0,041), the C-peptide level also increased significantly to 0,026+0,005ng/ml (p=0,016). The mean HbA1C level decreased significantly 3 months after the autologous HSCT from 13,09+1,92% to 9,22+1,94% (p=0,032).
Conclusions: The GLP-1level increases significantly within 3 months after the autologous HSCT in patients with type 1 DM. Thus, increased levels of  GLP-1and C-peptide with decrease of  HbA1C after the autologous HSCT may serve as a confirmation of  the effectiveness of such transplantation in type 1 DM.