Effect of cholecalciferol on cd3+cd25+ T cells in patients with severe sepsis

Abstract

Sepsis is a common complication in surgical patients and is the first cause of death in Intensive Care Unit (ICU) patients. The aim of this study was to identify the effect of cholecalciferol on the expression level of T helper 17 cells (Th17) and regulatory T cells (Tregs) in patients with severe sepsis, and to explore their role in immune function in severe sepsis. Forty patients with severe sepsis from Intensive Care Unit (ICU) were selected as the experimental group. Blood samples were collected from all patients on day 1 after their admission to ICU. CD3+CD25+ cells were isolated from blood specimens and used to measure the differentiation of CD3+CD25+ to Th17 cells and Treg cells under different concentrations of cholecalciferol: 0 nM, 1 nM, 5 nM and 10 nM. Apache II scores, Sofa Scores, blood pressure and platelet count decreased in the group with low cholecalciferol levels compared to the group with normal cholecalciferol level. The percentage of CD4+IL-17+ and CD8+IL-17+ cells decreased significantly in the 4 groups under cholecalciferol treatment in a dose-dependent manner. The percentages of CD4+CD25+Foxp3+ and CD8+CD25+Foxp3+ cells increased significantly in the 4 subgroups under cholecalciferol treatment in a dose-dependent manner. Cholecalciferol modulates the differentiation of CD3+CD25+ T cells into Th17 cells and Treg cells by decreasing the Th17 cells levels and increasing the Treg cell levels in a dose-dependent manner, suggesting that cholecalciferol level can affect the progression of severe sepsis patients.