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Updated: Jul 14, 2026

Fluorescence-Based Calcium Imaging in Primary Human Airway Epithelial Cultures Using Automated Cell Segmentation
Published on: May 22, 2026
Calcium-mediated, purinergic stimulation and polarized localization of calcium-sensitive adenylyl cyclase isoforms in
Marie-Christine Nlend1, Andreas Schmid, Zoltan Sutto
1Division of Pulmonary and Critical Care Medicine, University of Miami Miller School of Medicine, Miami, FL, USA.
Abstract:
Purinergic stimulation of human airway epithelia results in a prolonged increase in ciliary beat frequency that depends on calcium-mediated cAMP production [Lieb, T., Wijkstrom Frei, C., Frohock, J.I., Bookman, R.J. and Salathe, M. (2002) Prolonged increase in ciliary beat frequency after short-term purinergic stimulation in human airway epithelial cells. J. Physiol. (Lond.) 538, 633-646]. Here, fully differentiated human airway epithelial cells in culture are shown to express calcium-stimulated transmembrane adenylyl cyclase (tmAC) isoforms (types 1, 3, and 8) by reverse transcription polymerase chain reaction. Immunohistochemistry of tracheal sections and fully differentiated airway epithelial cell cultures revealed polarized expression of these tmACs, with types 1 and 8 localized to the apical membrane and thus at the position required for ciliary regulation. Real-time, ciliated-cell specific cAMP production by tmACs upon apical, purinergic stimulation with UTP was confirmed using fluorescent energy resonance transfer between fluorescently tagged PKA subunits.
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