Cholecalciferol supplementation improves suppressive capacity of regulatory T-cells in young patients with new-onset type 1 diabetes mellitus — A randomized clinical trial

• Published in: Clinical immunology (Orlando, Fla.) Fla.), 2015-12, Vol.161 (2), p.217-224
• Main Authors: Treiber, Gerlies, Prietl, Barbara, Fröhlich-Reiterer, Elke, Lechner, Evelyne, Ribitsch, Anja, Fritsch, Maria, Rami-Merhar, Birgit, Steigleder-Schweiger, Claudia, Graninger, Winfried, Borkenstein, Martin, Pieber, Thomas R
• Format: Article
• Language: English
• Subjects: Adolescent; Allergy and Immunology; C-Peptide - blood; Child; Cholecalciferol; Cholecalciferol - administration & dosage; Cholecalciferol - blood; Cholecalciferol - therapeutic use; Diabetes Mellitus, Type 1 - blood; Diabetes Mellitus, Type 1 - drug therapy; Diabetes Mellitus, Type 1 - immunology; Dietary Supplements; Double-Blind Method; Fasting - blood; Female; Humans; Male; Pilot Projects; Prospective Studies; Randomized controlled trial; Regulatory T cells; Suppressive capacity; T-Lymphocytes, Regulatory - drug effects; T-Lymphocytes, Regulatory - immunology; Time Factors; Treatment Outcome; Type 1 diabetes; Vitamin D; Vitamins - administration & dosage; Vitamins - therapeutic use
• ISSN: 1521-6616; 1521-7035
• DOI: 10.1016/j.clim.2015.08.002

Abstract It is unknown if cholecalciferol is able to modify defects in regulatory T cells (Tregs) in type 1 diabetes (T1D). In this randomized, double-blind, placebo controlled trial 30 young patients with new-onset T1D were assigned to cholecalciferol (70 IU/kg bodyweight/day) or placebo for 12 months. Tregs were determined by FACS-analysis and functional tests were assessed with ex vivo suppression co-cultures at months 0, 3, 6 and 12. Suppressive capacity of Tregs increased (p < 0.001) with cholecalciferol from baseline (− 1.59 ± 25.6%) to 3 (30.5 ± 39.4%), 6 (44.6 ± 23.8%) and 12 months (37.2 ± 25.0%) and change of suppression capacity from baseline to 12 months was significantly higher (p < 0.05) with cholecalciferol (22.2 ± 47.2%) than placebo (− 16.6 ± 21.1%). Serum calcium and parathormone stayed within normal range. This is the first study, which showed that cholecalciferol improved suppressor function of Tregs in patients with T1D and vitamin D could serve as one possible agent in the development of immunomodulatory combination therapies for T1D.