Response to inhaled corticosteroids on serum CD28, quality of life, and peak expiratory flow rate in bronchial asthma.

BACKGROUND

CD28 is a 44 kDa glycoprotein that is important in initiating T-cell responses and that results in increased T-cell proliferation and interleukin-2 production. This study estimated the serum CD28 levels in patients with asthma and evaluated the effect of inhaled corticosteroids (ICS) on the levels of CD28, the peak expiratory flow rate (PEFR), and quality of life (QOL).

METHODS

This prospective, open-label, observational study enrolled 40 adult patients with asthma of mild-to-moderate severity who were started on ICS and 40 healthy controls. Patients with bronchial asthma were evaluated for their serum CD28 level and QOL by using Mini Asthma Quality of Life Questionnaire scores, severity of symptoms, and PEFR at baseline and after 4 weeks.

RESULTS

The mean (standard deviation [SD]) serum CD28 concentration in patients with asthma was 107 ± 4.98 ng/mL, which was significantly elevated (p < 0.01) compared with the healthy individuals (37.67 ± 18.28 ng/mL). ICS treatment for 4 weeks reduced the mean (SD) serum CD28 levels to 40.9 ± 2.82 ng/mL. PEFR increased significantly, from 190.75 ± 10.55 to 263 ± 10.69 L/min (p < 0.01) after 4 weeks. Similarly, the mean (SD) Mini Asthma Quality of Life Questionnaire scores significantly increased, from 36.90 ± 10.31 on day 0 to 70.63 ± 11.56 on day 28 after ICS therapy (p < 0.01). A negative correlation between the elevations of serum CD28 levels was seen with QOL.

CONCLUSION

The serum CD28 concentration, a marker of inflammation, is increased in bronchial asthma and reduced by ICS therapy. ICS also improved QOL scores and objective clinical outcomes in patients with asthma.