Home - Type 1 Diabetes - Autoimmune Liver Disease
Publications - Collaborations - Group Members - Contact
Kerstin Rose, Monika Bayer and Urs Christen
In collaboration with:
Elizabeth Ramos-Lopez and Klaus Badenhoop (Goethe University Hospital Frankfurt, Germany)
Vitamin D (VD) has been implicated in type 1 diabetes (T1D) by genetic and epidemiological studies. Individuals living in regions with low sunlight exposure have an increased T1D risk and VD-supplementation reduced the risk in human individuals and mouse models. One possibility of how VD influences the pathogenesis of T1D is its immunomodulatory effect on dendritic cells (DC), which than preferentially activate regulatory T-cells (Treg). In the present pilot study, we collected blood samples from a small cohort of patients with T1D at baseline, months 6 and 12. VD-deficient patients were advised to supplement with 1000 IU/day VD. We found a considerable variation in the VD plasma level at baseline and follow-up. However, with higher VD plasma levels a lower frequency of IL-4-producing CD8 T cells was observed. We further performed a comprehensive genotyping of thirteen VD-related polymorphisms and found an association between VD plasma level and the genotype of the VD binding protein (DBP). The frequency of DC and T-cell subsets was variable in patients of all subgroups and in individual patients over time. Nevertheless, we found a few significant associations including the 1,25-dihydoxyvitamin D3 hydroxylase (CYP27B1) genotype with the frequency of DC subtypes. In summary, our preliminary results indicate only a limited influence of the VD plasma level on the immune balance in patients with T1D. Nevertheless, our pilot study provides a basis for a follow-up study with a larger cohort of patients.
Publication: Influence of the vitamin D plasma level and vitamin D related genetic polymorphisms on the immune status of patients with type 1 diabetes: A pilot study
Rose et al (2013) Clin Exp Immunol (in press)