OBJECTIVE: To investigate the correlation between the polymorphism of IL-4 and IL-10 gene promoters and the susceptibility of Chinese children to asthma and to study the impact of such polymorphism upon cytokine production. METHODS: The data of medical history, pulmonary function, hypersensitive test, and serum IgE were recorded among 168 unrelated Chinese children with asthma aged 5 approximately 15. Four polymorphism sites of IL-4 and IL-10 gen promoter regions were determined by PCR/RFLP. The peripheral blood monocyte (PBMC) was cultured and stimulated by lipopolysacchride (LPS). Then the contents of IL-4 and IL-10 gene promoter regions were determined by ELISA. 53 age-matched children without asthma were used as control. RESULTS: (1) The allele frequencies of-598 (C/T) site of IL-4 gene promoter was significantly different between Chinese children and children of Caucasian and Afro-American origin (P = 0.01). The allele frequency of -1082 (G/A) site, -819 (C/T) site, and -592 (A/C) site in IL-10 gene promoter was significantly different between Chinese children and their British counterparts (P = 0.01). (2) The serum total IgE level was significantly different among children with different allelic sites in IL-4 and IL-10 gene promoters. A allele in IL-10 - 1082 (G/A) site and T allele in IL-10 - 819 (C/T) site -1082 were associated with elevated total serum IgE (P < 0.01, OR = 3.16; P < 0.05, OR = 1.84). (3) The IL-10 level in the supernatant of PBMC culture of children with homozygous genotypes of -819 TT and ATA/ATA in IL-10 gene promoter after stimulation of LPS was the lowest in comparison with those in the supernatant of PBMC culture of children with other genotypes (all P < 0.05). (4) No correlation was found between -589 (C/T) site in IL-4 gene promoter and asthma. There was no significant difference between the increase of IL-4 level in the supernatant of PBMC culture of children with the two different homozygous genotypes of IL-4 gene promoter. CONCLUSIONS: (1) There is no significant correlation between the polymorphism sites in IL-4 and IL-10 gene promoters and the susceptibility to asthma among Chinese. (2) The polymorphism of IL-10 gene promoter may be an important candidate gene for severity of asthma. The allele -819T plays an important role in increase of the total serum IgE by reducing the upregulation of IL-10 gene expression.
OBJECTIVE: To investigate the correlation between the polymorphism of IL-4 and IL-10 gene promoters and the susceptibility of Chinese children to asthma and to study the impact of such polymorphism upon cytokine production. METHODS: The data of medical history, pulmonary function, hypersensitive test, and serum IgE were recorded among 168 unrelated Chinese children with asthma aged 5 approximately 15. Four polymorphism sites of IL-4 and IL-10 gen promoter regions were determined by PCR/RFLP. The peripheral blood monocyte (PBMC) was cultured and stimulated by lipopolysacchride (LPS). Then the contents of IL-4 and IL-10 gene promoter regions were determined by ELISA. 53 age-matched children without asthma were used as control. RESULTS: (1) The allele frequencies of-598 (C/T) site of IL-4 gene promoter was significantly different between Chinese children and children of Caucasian and Afro-American origin (P = 0.01). The allele frequency of -1082 (G/A) site, -819 (C/T) site, and -592 (A/C) site in IL-10 gene promoter was significantly different between Chinese children and their British counterparts (P = 0.01). (2) The serum total IgE level was significantly different among children with different allelic sites in IL-4 and IL-10 gene promoters. A allele in IL-10- 1082 (G/A) site and T allele in IL-10 - 819 (C/T) site -1082 were associated with elevated total serum IgE (P < 0.01, OR = 3.16; P < 0.05, OR = 1.84). (3) The IL-10 level in the supernatant of PBMC culture of children with homozygous genotypes of -819 TT and ATA/ATA in IL-10 gene promoter after stimulation of LPS was the lowest in comparison with those in the supernatant of PBMC culture of children with other genotypes (all P < 0.05). (4) No correlation was found between -589 (C/T) site in IL-4 gene promoter and asthma. There was no significant difference between the increase of IL-4 level in the supernatant of PBMC culture of children with the two different homozygous genotypes of IL-4 gene promoter. CONCLUSIONS: (1) There is no significant correlation between the polymorphism sites in IL-4 and IL-10 gene promoters and the susceptibility to asthma among Chinese. (2) The polymorphism of IL-10 gene promoter may be an important candidate gene for severity of asthma. The allele -819T plays an important role in increase of the total serum IgE by reducing the upregulation of IL-10 gene expression.
Authors: Yohan Bossé; Mathieu Lemire; Audrey H Poon; Denise Daley; Jian-Qing He; Andrew Sandford; John H White; Alan L James; Arthur William Musk; Lyle J Palmer; Benjamin A Raby; Scott T Weiss; Anita L Kozyrskyj; Allan Becker; Thomas J Hudson; Catherine Laprise Journal: Respir Res Date: 2009-10-24