Copyright ©ERS Journals Ltd 2002 Studying human airway pharmacology in microsections: application of videomicrometry1 Leiden University Medical Centre, Dept of Pulmonology, Leiden, the Netherlands. 2 University of Southampton School of Medicine, Respiratory Cell and Molecular Biology Section, Division of Infection, Inflammation and Repair, Southampton, UK. 3 University of Chicago, Section of Pulmonary and Critical Care Medicine and Committee on Cell Physiology and Clinical Pharmacology, Chicago, IL, USA CORRESPONDENCE: K.F. Rabe, Leiden University Medical Centre, Dept of Pulmonology, C3-P, P.O. Box 9600, NL-2300 RC, Leiden, The Netherlands. Fax: 31 715266927. E-mail: K.F.Rabe@lumc.nl Keywords: bronchi, epithelium, eosinophils, immunological sensitization, smooth muscle, video microscopy
Received: June 28, 2001
This work was funded by grants from the German Ministry for Research and Technology (BMFT 01 KE 9301) and the National Institutes of Health (HL-46368, SCOR HL-56399, NIAID V01-AI-34566).
The influence of endogenously-released mediators and activated eosinophils on the airway lumen and the effect of passive sensitization on anti-immunoglobulin (Ig)-E-induced contractile responses was investigated by videomicrometry.
Human bronchial sections of 23 mm internal diameter, placed in 250 µL Hank's balanced salt solution on microtitre plates, were monitored and recorded by digitized image analysis. Airway preparations exhibited a spontaneous narrowing (mean±sem 33±5% of the luminal area). Removal of the bronchial epithelium almost completely prevented the development of spontaneuous narrowing (6±3%; p<0.001). The addition of platelet-activating factor stimulated human eosinophils to the bronchial sections led to significant narrowing of the airway lumen (39±9%; p<0.05). Passive sensitization induced hyperresponsiveness to polyclonal anti-IgE (35±8%; p<0.01).
It is concluded that videomicrometry is suitable for studying interactions between human airways and inflammatory cells, as well as the effect of passive sensitization on smooth muscle reactivity in vitro, without the imposition of preload. Under these conditions, human airways exhibited a spontaneous decrease of the airway lumen over time suggesting a role for epithelium-derived mediators because the development of spontaneous tone was epithelium dependent.
This article has been cited by other articles:
| ||||||||||||||||||||||||||||||||||||