association of regulatory t cells with diabetes type-1 and its renal and vascular complications based on the expression of forkhead box protein p3 (foxp3), helios and neurophilin-1

In recent years, it has been recognized that regulatory t cells (tregs) play a critical role in maintaining immune tolerance. moreover, the expression of two markers named helios and neurophilin-1 (nrp-1) has been highlighted in such cells. helios, an intracellular transcription marker, largely differentiates twomost operative sub group of tregs, namely naturally occurring (ntreg) and induced (itreg) tregs, and nrp-1 is reckoned as a membranous activity marker of tregs. we aimed to count peripheral mononuclear cells expressing such markers in a group of type 1 diabetes patients to elucidate the possible role of tregs in the pathogenesis of such disease and its complications. blood samples from 61 adult patients with type 1 diabetes and 61 sex and age-matched healthy controls were tested to count two types of tregs, namely naturally occurring and inducible types, according to the expression of cell surface markers of cd4/cd25/cd47–fitc/pe/apc and intracellular markers of foxp3/helios–pe-cy5/eflour450 by flow cytometry, respectively.we also investigated the relation between expression of such markers with hba1c, urine albumin/creatinine ratio (uacr), and common carotid intima thickness (cimt). the circulatory frequency of both helios+ and helios- t-cells were significantly decreased in patients compared to those in healthy controls (p<0.001). there was also a significant decrease in circulatory frequency of helios+ nrp-1+ and helios- nrp-1+ cells in the patients compared to controls (p=0.029). according to expression of helios and nrp-1 markers, the number and function of both tregs were decreased in diabetic patients. moreover, the neurophilin expression was inversely associated with complications of type 1 diabetes.