Figure 5.

The frequency of mast cell progenitors is increased in subjects with reduced lung function. The frequencies of Lin⁻ CD34^hi CD117^int/hi FcεRI⁺ mast cell progenitors (MCp) were quantified from 24 blood donors by flow cytometry. (A) The subjects were grouped according to the classification in the MIDAS baseline study. (B) The asthmatic subjects, classified at the baseline study, were divided into 2 groups based on the prebronchodilator FEV1 values expressed as percent of the predicted at the time of blood mast cell progenitor analysis. (C) All subjects including healthy controls were divided into 2 groups based on the prebronchodilator FEV1 values expressed as percent of the predicted at the time of blood mast cell progenitor analysis. One of the healthy controls had developed asthma prior to our follow-up study when blood was sampled (shown as a triangle). One patient diagnosed with nonallergic asthma in the baseline study is shown as a square. Differences between groups were evaluated by 2-tailed unpaired Student t tests of the log-transformed data. The geometric mean values and all subjects are shown.