The role of regulatory CD4+CD25+high T-lymphocytes and their functional activity in the development of type 1 diabetes mellitus

Abstract

Type 1 diabetes mellitus (DM1) is associated with compromised (defective) immunologic tolerance to autoantigens and selective destruction of pancreatic B-cells by CD4+ (effector) and CD8 (cytotoxic) lymphocytes. The mechanisms of autotolerance involve CD4+CD25+high T-regulatory cells (Treg) whose suppressor activity depends on the expression of the FoxP3 gene. Aim. Detection of quantitative and functional alterations at the level of regulation of immunity in subjects at risk of DM1 and patients with different duration of DM1. Materials and methods. 116 patients (67 men and 49 women) with different duration of DM1. The risk group was comprised of 33 subjects (10 men and 23 women), control group included 16 subjects. In all cases, HLA genotyping was performed, autoantibodies to GDC, insulin and tyrosine phosphatase, islet cell antigens were determined, subpopulation composition of CD3+, CD4+, CD8+, CD38+, HLA DR+, CD25+, CD4+25+ lymphocytes and their functional activities (FoxP3 gene expression) studied, C-peptie and HbA1c levels measured. Results. A tendency toward a rise in Cd25+ and CD4+25+ T-lymphocytes and a decrease in FoxP3 expression was documented in the risk group compared with control (p0.05) but their functional activity was lower (p

Keywords

• type 1 diabetes mellitus
• subjects at risk if dm1
• cd4+cd25+high regulatory t-lymphocytes
• foxp3 gene