Human airway epithelial cells express interleukin-2 in vitro. Aoki, Yosuke, Daoming Qiu, Anne Uyei, and Peter N. Kao. Pulmonary and Critical Care Medicine, Stanford University Medical Center, MSLS P322, Stanford, CA 94305
APStracts 3:0208L, 1996.
Human airway epithelial cells (AECs) produce T-cell growth factor, IL -2, which likely modulates the T-cell lung inflammatory response. IL-2 mRNA from cultured AECs and from Jurkat T-cells was analyzed by RT -PCR and Northern hybridization. IL-2 mRNA is present constitutively in AECs, and is enhanced 2-fold following stimulation with phorbol 12-myristate 13-acetate (PMA, 20ng/ml) + histamine (2mM). Normal human AECs secrete IL-2 at rest (7 pg/ml), and IL-2 secretion is increased 3-fold following stimulation with PMA + histamine, and this increase is inhibited by dexamethasone and diphenhydramine. Transcriptional regulation of IL-2 was investigated with a transgenic human AEC line, 16HBE/IL-2 luciferase: there is constitutive IL-2 transcription at rest, and IL-2 transcription is enhanced 8-fold by PMA, and 25-fold by PMA + histamine. IL-2 regulation differs fundamentally between AECs and Jurkat T-cells. AEC IL-2 likely promotes local proliferation of T-cells, and may contribute to pathologic airway inflammation in asthma.

Received 21 May 1996; accepted in final form 24 September 1996.
APS Manuscript Number L147-6.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996