Changes of natural killer T cells levels in peripheral blood of children with asthma and clinical significance / 中华实用儿科临床杂志

ABSTRACT

Objective To study the changes of natural killer T cells (NKT cells) in peripheral blood and the ability of NKT cells to proliferate in response to alpha-galactosyl ceramide (α-Galcer) in children with asthma.Methods Fifty-two asthmatic children who were diagnosed by Pediatric Clinic of Renji Hospital Affiliated to Shanghai Jiaotong University Medical College from Feb.2009 to Mar.2012 were selected as asthmatic group (26 cases in intermittent group,14 cases in mild persistent group and 12 cases in moderate persistent group).Twenty healthy children were selected as healthy control group.Peripheral blood mononuclear cells were collected by way of density gradient centrifugation method from blood samples.The ratio of peripheral blood NKT and CD4 + NKT cells were assessed by immunolluorescence and flow cytometry assays.The relationships between the NKT cells number,CD4 + NKT cells and atopic indexes such as the total IgE,eosinophil cationic protein (ECP) and the severity of asthma were investigated.The levels of IFN-γ,IL-4,IL-10 in peripheral blood were measured by enzyme-linked immunosorbent assay after proliferate in response to α-Galcer.The data were analyzed by using statistics software.Results Compared with healthy control group,the ratio of peripheral blood NKT and CD4 + NKT cells in asthmatic patients were significantly decreased (all P ＜0.01) ; There were no significant differences in asthmatic patients among the subgroups in terms of severity (P ＞ 0.05).There was no significant correlation between the NKT cells,CD4 + NKT cells and atopic indexes such as the total IgE and ECP(all P ＞ 0.05).The level of IL-4 in serum secreted by NKT cells in asthmatic group was significantly higher than that of healthy control group (P ＜0.01) ;The level of IL-10 in serum secreted by NKT cells in asthmatic group was decreased significantly (P ＜0.01) ;There was no significant difference in IFN-γ secreted by NKT cells between the asthmatic group and healthy control group (P ＞ 0.05).Conclusion The pathogenesis of asthma may be related to the ratio and dysfunction of NKT cells and CD4 + NKT cells.