[Activation of CD4+ T cells and increased release of interleukin-5 in cultures of bronchoalveolar lavage cells and PBMC from patients with asthma].
To investigate the roles of CD4+ T cells and Th2 cytokine interleukin (IL)-5 in asthma, we examined the activation of CD4+ T cells and IL-5 production in cultures of bronchoalveolar lavage (BAL) cells and PBMC with and without allergen stimulation, in vitro, in 12 atopic asthmatic, 10 non-atopic asthmatic and 9 atopic non-asthmatic patients, as well as 10 normal control subjects. The patients with atopic and non-atopic asthma had significantly increased percentages of CD4+ T cells expressing CD25 (10.1% +/- 1.8% and 10.6% +/- 2.9%) and HLA-DR (11.2% +/- 3.1% and 12.0% +/- 3.6%, respectively) as compared with normal control subjects (P < 0.01) in unstimulated BAL cell cultures. IL-5 levels in the supernatants of those BAL cells from atopic and non-atopic asthmatic patients significantly enhanced (43.8 +/- 14.2 pg/ml and 85.5 +/- 15.1 pg/ml) as compared with those for atopic non-asthmatic and normal control subjects (P < 0.01). Meanwhile, increased percentages of activated CD4+ T cells and IL-5 secretion were also observed in the cultures of unstimulated PBMC from both types of asthmatic patients. In the cultures of allergen-stimulated BAL cells and PBMC, atopic asthmatic patients demonstrated marked increase in the percentage of CD4+ CD25+ T cells (17.9% +/- 13.9% and 29.0% +/- 27.5%) and IL-5 production (30.5 +/- 13.3 pg/ml and 109.3 +/- 35.0 pg/ml, for BAL cell and PBMC cultures respectively) as compared with nona-topic asthmatic patients (P < 0.01). Although the percentages of activated CD4+ T cells and IL-5 secretion elevated significantly in allergen-stimulated culture of PBMC from atopic non-asthmatic subjects, the IL-5 release by the allergen-stimulated BAL cells from the same subjects were still significantly lower than both forms of asthmatic patients (P < 0.01). Our findings show that activation of CD4+ T cells and IL-5 production are strongly implicated in the pathogenesis of both atopic and non-atopic asthma.
Tang
C
C
202nd Hospital, PLA, Shenyang.
Quan
B
B
Wang
D
D
D000328:Adult; D001249:Asthma / Q000276:immunology*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology / Q000276:immunology*; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D015848:Interleukin-5 / Q000096:biosynthesis*; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D006377:T-Lymphocytes, Helper-Inducer / Q000276:immunology*
D015848:Interleukin-5