Interleukin 6 receptor expression on human bronchial epithelial
cells: regulation by interleukin 1 and interleukin 6.
Takizawa, Hajime, Takayuki Ohtoshi, Naomi Yamashita, Teruaki Oka, and
Koji Ito.
Department of Medicine and Physical Therapy and Department of
Pathology, University of Tokyo School of Medicine, Tokyo, Japan
APStracts 2:0169L, 1995.
Airway epithelial cells have a potential to participate in regulation
of local homeostasis by releasing active compounds including
cytokines and growth factors. Several factors such as transforming
growth factor-[beta] and endothelin have been shown to regulate
airway epithelial cell functions through an autocrine mechanism. We
studied the expression of the specific receptor for a multifunctional
cytokine interleukin 6 ( IL-6 ), which is expressed and released by
airway epithelial cells. Specific binding assay demonstrated a single
set of binding sites on human primary and transformed bronchial
epithelial cells. Human recombinant interleukin-1[alpha] ( IL
-1[alpha] ) increased maximal binding sites to IL-6. Northern blot
analysis demonstrated that airway epithelial cells constitutively
expressed mRNA for IL-6 receptor, and IL-1 and IL-6 itself
upregulated IL-6R gene expression. Moreover, exogenously added human
recombinant IL-6 had a stimulatory effect on interleukin-8 release
from human bronchial epithelial cells. These results indicated that
human bronchial epithelial cells expressed IL-6R, and IL-6 might be
involved in the regulation of the epithelial functions via an
autocrine as well as a paracrine mechanism.
Received 19 August 1994; accepted in final form 13 September
1995.
APS Manuscript Number L244-4.
Article publication pending Am. J. Physiol. (Lung Cell. Mol.
Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 31 October 95