JCB logo
MBoC5 from Garland Science
  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents

This Article
Right arrow Full Text
Right arrow PDF (Full Text)
Right arrow PPT slides of all figures
Right arrow Alert me when this article is cited
Right arrow Citation Map
Services
Right arrow Email this article
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new content in the JCB
Right arrow Download to citation manager
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Millward-Sadler, S.J.
Right arrow Articles by Salter, D.M.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Millward-Sadler, S.J.
Right arrow Articles by Salter, D.M.
Social Bookmarking
 Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati  
What's this?

J. Cell Biol., Volume 145, Number 1, April 5, 1999 183-189

Integrin-regulated Secretion of Interleukin 4: A Novel Pathway of Mechanotransduction in Human Articular Chondrocytes

S.J. Millward-Sadler,* M.O. Wright,Dagger H.-S. Lee,*§ K. Nishida,* H. Caldwell,* G. Nuki,parallel and D.M. Salter*

* Department of Pathology and Dagger  Department of Physiology, University of Edinburgh Medical School, Edinburgh, United Kingdom EH8 9AG; § National Defense Medical Center and Tri-Service General Hospital, Taiwan 100; and parallel  Rheumatic Diseases Unit, Western General Hospital, Edinburgh, United Kingdom EH4 2XU

Chondrocyte function is regulated partly by mechanical stimulation. Optimal mechanical stimulation maintains articular cartilage integrity, whereas abnormal mechanical stimulation results in development and progression of osteoarthritis (OA). The responses of signal transduction pathways in human articular chondrocytes (HAC) to mechanical stimuli remain unclear. Previous work has shown the involvement of integrins and integrin-associated signaling pathways in activation of plasma membrane apamin-sensitive Ca2+-activated K+ channels that results in membrane hyperpolarization of HAC after 0.33 Hz cyclical mechanical stimulation. To further investigate mechanotransduction pathways in HAC and show that the hyperpolarization response to mechanical stimulation is a result of an integrin-dependent release of a transferable secreted factor, we used this response. Neutralizing antibodies to interleukin 4 (IL-4) and IL-4 receptor alpha  inhibit mechanically induced membrane hyperpolarization and anti-IL-4 antibodies neutralize the hyperpolarizing activity of medium from mechanically stimulated cells. Antibodies to interleukin 1beta (IL-1beta ) and cytokine receptors, interleukin 1 receptor type I and the common gamma  chain/CD132 (gamma ) have no effect on me- chanically induced membrane hyperpolarization. Chondrocytes from IL-4 knockout mice fail to show a membrane hyperpolarization response to cyclical mechanical stimulation. Mechanically induced release of the chondroprotective cytokine IL-4 from HAC with subsequent autocrine/paracrine activity is likely to be an important regulatory pathway in the maintenance of articular cartilage structure and function. Finally, dysfunction of this pathway may be implicated in OA.

Key words: chondrocyte;  mechanotransduction;  integrin;  interleukin 4;  ion channels


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati    What's this?


This article has been cited by other articles:



  Home | Help | Feedback | Subscriptions | Archive | Search | Table of Contents