Monitoring of Autoantibodies Following Autologous Hematopoietic Stem Cell Transplantation in 6 Children with Recently Diagnosed Type 1 Diabetes Mellitus.

BACKGROUND Bone marrow stem cells have been shown to be a promising therapeutic strategy for autoimmune diseases. This study aimed to assess the safety and efficacy of autologous hematopoietic stem cell (ABMSC) transplantation without immunoablation used to suppress the autoimmune reaction in 6 children with newly diagnosed autoimmune diabetes mellitus. We monitored the levels of islet cell antibodies (ICA), antibodies against islet antigen-related tyrosine phosphatase 2 (IA2), glutamic acid-decarboxylase (GAD) antibodies, and anti-insulin antibodies (AIA). MATERIAL AND METHODS Between 2018 and 2022, 6 children (age 6-10 years, average 8 years) recently diagnosed with type 1 diabetes mellitus with the presence of ICA, IA2, GAD, AIA and ketoacidosis, were treated with an ABMSC stimulated with Filgrastim, granulocyte colony-stimulating factor (G-CSF), 10 ug/kg/day for 4 days. Bone marrow was harvested on day 5, collected by puncture and identified as mononuclear cells >180×10⁶/kg, CD34+ >0.22%, and transplanted by intravenous (i.v.) infusion. Patients were monitored with ICA, IA2, GAD, AIA, C-peptide, blood glucose, and glycosylated hemoglobin A1c (HbA1C) 6 months after the procedure. RESULTS At 6-month follow-up, we observed a negative value of the ICA, which was previously positive (P<0.001). The IA2 (p=0.037) and GAD (P=0.377) antibodies decreased slowly but were significantly lower. AIA remained high. A decrease in blood glucose and HbA1C levels was observed (P<0.001). No complications occurred during follow-up. CONCLUSIONS Autologous hematopoietic stem cell transplantation without immunoablation was safe and effective in significantly decreasing the production and effect of autoantibodies against ICA, GAD, and IA2, as well as decreasing blood sugar levels and HbA1c.