Changes and significance of monocytic myeloid-derived suppressor cells during acute phase of Kawasaki disease / 中华微生物学和免疫学杂志

ABSTRACT

Objective:To investigate the changes of monocytic myeloid-derived suppressor cells (M-MDSC) in children with acute Kawasaki disease (KD) and its roles in the immunological pathogenesis of KD.Methods:A total of 38 children with acute KD were enrolled in the present study and 32 age-matched healthy children were selected as control group. The proportions of HLA-DR -CD11b + CD33 + CD15 -CD14 + M-MDSC and CD4 + CD25 + CD127 - regulatory T cells (Treg) in peripheral blood, concentrations of reactive oxygen species (ROS) and expression of arginase-1 (Arg-1), CD39, CD73, CD40, CD40L and CCR5 at protein levels were detected by flow cytometry. Quantitative real-time PCR was used to evaluate the transcription levels of inducible nitric oxide synthase (iNOS) in M-MDSC and the transcription levels of cytotoxic T-lymphocyte associated antigen 4 (CTLA4) and lymphocyte-activation gene 3 (LAG3) in Treg. Concentrations of NO, CCL3, CCL4, CCL5, IL-10 and TGF-β in the supernatants of cell culture were measured by ELISA. Results:(1) The proportion of HLA-DR -CD11b + CD33 + CD15 -CD14 + M-MDSC, the concentration of intracellular ROS and the expression of iNOS, CD39 and CD73 in M-MDSC decreased significantly in patients with acute KD as compared with those in the control group ( P<0.05), and the concentrations of NO, IL-10 and TGF-β in culture supernatant of M-MDSC were lower than those in the control group upon lipopolysaccharide (LPS) stimulation for 48 h ( P<0.05). All of the aforementioned indexes restored to some extent after intravenous immunoglobulin (IVIG) therapy ( P<0.05). No statistical differences were found in Arg-1 expression between healthy controls and patients with KD before or after IVIG therapy ( P<0.05). (2) CD40 expression on M-MDSC was significantly lower in the acute KD group than in the control group ( P<0.05). The concentrations of CCL3, CCL4 and CCL5 in the culture supernatants of M-MDSC were lower in the acute KD group than in the control group after LPS stimulation ( P<0.05). With IVIG treatment, all of the indexes were up-regulated significantly ( P<0.05), although CD40 expression was still lower in the acute KD group than in the control group ( P<0.05). (3) The proportion of CD4 + CD25 + CD127 -Treg and the expression of CTLA4, LAG3, CD40L and CCR5 reduced significantly in patients with acute KD as compared those in healthy controls ( P<0.05), and all increased remarkably after IVIG therapy ( P<0.05). Pearson correlation analysis showed a positive correlation between the proportions of M-MDSC and Treg in patients with acute KD ( r=0.58, P<0.05). Conclusions:Insufficiency and impaired function of M-MDSC might be a major cause of immune dysfunction in patients with acute KD.