Light microscopic photographic images of airway tissue sections obtained from a non-asthmatic (A) and an asthmatic (B) patient.

<p>Images (magnification 60×) are representative of tissues obtained from 3 non-asthmatic and 7 asthmatic patients stained with Haematoxylin-Eosin. Note the increased thickening of the basement membrane in the asthmatic airways. E = epithelium, arrows are indicating the basement membrane.