Effects of theophylline on CD4+ T lymphocyte, interleukin-5, and interferon gamma in induced sputum of asthmatic subjects.
Abstract
AIM: To investigate the mechanism of anti-inflammatory action of theophylline on
asthma.
METHODS: Nineteen asthmatic subjects were administered 200 mg sustained-release
theophylline twice daily for 4 weeks. The number of CD4+ T lymphocytes,
eosinophils, and the levels of interleukin (IL)-5 and interferon gamma
(IFN-gamma) in sputum pre- and post-administration were measured by direct
immunofluorescene technique, Wright's stain and enzyme-linked immunosorbent
assay, respectively. The symptom scores and lung function were also evaluated.
RESULTS: Theophylline treatment significantly improved symptom scores and FEV1.0,
FEV1.0 % (P < 0.05) and reduced sputum eosinophils (P < 0.01) in asthmatic
subjects. These were accompanied by a decrease in sputum IL-5 level (P < 0.01),
but sputum CD4+ T lymphocytes and IFN-gamma had no significant change (P >0.05).
The mean (range) serum theophylline concentration in final steady state was 7.9
(3.9 - 12.9) mg/L.
CONCLUSION: The anti-inflammatory action of theophylline in asthma may result
from reduction of IL-5 production in the airways.
Keywords:
asthma.
METHODS: Nineteen asthmatic subjects were administered 200 mg sustained-release
theophylline twice daily for 4 weeks. The number of CD4+ T lymphocytes,
eosinophils, and the levels of interleukin (IL)-5 and interferon gamma
(IFN-gamma) in sputum pre- and post-administration were measured by direct
immunofluorescene technique, Wright's stain and enzyme-linked immunosorbent
assay, respectively. The symptom scores and lung function were also evaluated.
RESULTS: Theophylline treatment significantly improved symptom scores and FEV1.0,
FEV1.0 % (P < 0.05) and reduced sputum eosinophils (P < 0.01) in asthmatic
subjects. These were accompanied by a decrease in sputum IL-5 level (P < 0.01),
but sputum CD4+ T lymphocytes and IFN-gamma had no significant change (P >0.05).
The mean (range) serum theophylline concentration in final steady state was 7.9
(3.9 - 12.9) mg/L.
CONCLUSION: The anti-inflammatory action of theophylline in asthma may result
from reduction of IL-5 production in the airways.