Age distribution characteristics of intestinal segmented filamentous bacteria and their relationship with intestinal mucosal immunity in children / 中国当代儿科杂志

OBJECTIVE@#To investigate the age distribution characteristics of intestinal segmented filamentous bacteria (SFB) in children and their relationship with intestinal mucosal immunity.@*METHODS@#The fresh feces of 177 children and the ileocecal fluid of 47 children during colonoscopy were collected. The SFB was determined by real-time PCR. The concentration of secretory immunoglobulin A (sIgA) was determined by enzyme-linked immunosorbent assay. The numbers of interleukin 17A (IL-17A) cells and intraepithelial lymphocytes in the terminal ileum mucosa and the expression of transcription factors associated with the differentiation of T helper (Th) cells, T-box transcription factor (T-bet), forkhead box P3 (FOXP3), and retinoid-related orphan receptor gamma t (ROR-γt), were determined by immunohistochemistry.@*RESULTS@#The positive rate of intestinal SFB in these children was 19.2% (34/177). Trend analysis showed that the positive rate of SFB was correlated with age: the rates for children aged 0-, 1-, 2-, 3-, 4-, 5-, 6-, and 7-15 years were 40%, 47%, 32%, 15%, 12%, 13%, 15% and 4% respectively (P<0.001). The concentration of sIgA in intestinal fluid was significantly higher in SFB-positive children (n=24) than in SFB-negative children (n=23) (P<0.01). The number of intraepithelial lymphocytes in the terminal ileum mucosa and the expression of T-bet, FOXP3, and ROR-γt were not significantly different between the SFB-positive group (n=12) and the SFB-negative group (n=11), but the number of IL-17A cells in the terminal ileum mucosa was significantly lower in the SFB-positive group than in the SFB-negative group (P<0.05).@*CONCLUSIONS@#Intestinal SFB colonization in children is age-related, and the colonization rate is relatively high in children under 3 years old. In SFB-positive children, the secretion of intestinal sIgA is increased, while the number of IL-17A cells in the terminal ileum is reduced.

Effect of atopy on serum glucocorticoid receptor levels in children with bronchiolitis / 中国当代儿科杂志

<p><b>OBJECTIVE</b>To investigate the effect of atopy on the expression of glucocorticoid receptors in children with bronchiolitis.</p><p><b>METHODS</b>ELISA was used to measure the changes in the serum levels of glucocorticoid receptor α (GRα) and glucocorticoid receptor β (GRβ) in the bronchiolitis group (77 children, including 34 children with atopy) and pneumonia group (68 children). Thirty-eight children who were prepared to undergo surgeries for non-infectious diseases and had no atopy or family history of allergic diseases were enrolled as the control group.</p><p><b>RESULTS</b>The bronchiolitis group and the pneumonia group had significant increases in the serum levels of GRα and GRβ compared with the control group (P<0.01), and the bronchiolitis group had significant increases in these levels compared with the pneumonia group (P<0.01). Compared with the control group and the pneumonia group, the bronchiolitis group had a significant increase in the GRα/GRβ ratio (P<0.01). Compared with the control group, the children with or without atopy in the bronchiolitis group had significant increases in the serum levels of GRα and GRβ (P<0.01). The non-atopic children in the bronchiolitis group had a significant increase in the serum level of GRβ compared with the atopic children (P<0.01). The atopic children in the bronchiolitis group had a significant increase in the GRα/GRβ ratio compared with the control group and non-atopic children in the bronchiolitis group (P<0.01).</p><p><b>CONCLUSIONS</b>Children with bronchiolitis have increased serum levels of GRα and GRβ. The children with atopy have an increased GRα/GRβ ratio, suggesting that the atopic children with bronchiolitis are highly sensitive to glucocorticoids.</p>