T REGULATORY CELLS IN CORD BLOOD OF CHILDREN OF DIABETIC MOTHERS

Type 1 diabetes (T1D) develops due to autoimmune pancreatic beta cells destruction. The effect of diabetes on pregnancy outcome is well documented. However, much less is known about the effect of maternal diabetes on the developing foetal immune system. The risk of T1D development in a child of T1D mother who was diagnosed prior pregnancy is lower than e. g. in a child of T1D father. This discrepancy supports the theory that there is some immunoregulatory influence on her baby. For this reason we decided to study T regulatory cells (Tregs) which are important in immunoregulation and for autoimmune diseases pathogenesis. Moreover Tregs cord blood (CB) studies of T1D mothers are limited. Tregs defined as CD45(+) CD3(+) CD4(+) CD25(+) CD127((low/-)) in CB samples were investigated in our study by flow cytometry and 17 T1D mothers, 17 gestation diabetes mothers and 42 healthy controls were enrolled. We found just that CB from babies of T1D mothers contained 6,73 % Tregs/total Th- lymfocytes in comparison to 9,25 % in controls (p = 0,043). Other differences were not significant. If an establishment of specific immunological tolerance in foetus of T1D mother really exists, it seems to be rather due to other factors than just to changes in Tregs count (which was moreover found to be decreased). We are currently focused on explanation why children of T1D mothers suffer from diabetes less frequently than other first degree relatives by using functional analysis of Tregs. Insights in to this phenomenon would be useful e.g. for construction of T1D immunointervention therapy.