Journal Article

CD44 binds a chondroitin sulfate proteoglycan, aggrecan

Takashi Fujimoto, Hiroto Kawashima, Toshiyuki Tanaka, Mayumi Hirose, Noriko Toyama-Sorimachi, Yuji Matsuzawa and Masayuki Miyasaka

in International Immunology

Published on behalf of Japanese Society for Immunology

Volume 13, issue 3, pages 359-366
Published in print March 2001 | ISSN: 0953-8178
Published online March 2001 | e-ISSN: 1460-2377 | DOI:
CD44 binds a chondroitin sulfate proteoglycan, aggrecan

More Like This

Show all results sharing these subjects:

  • Immunology
  • Biological Sciences


Show Summary Details


Here we report that CD44 binds a chondroitin sulfate (CS) proteoglycan, aggrecan, a major component of cartilage. Soluble CD44–IgG and CD44+ cells bound to aggrecan from rat chondrosarcoma and bovine cartilage, immobilized on microtiter plates. In both cases, binding was blocked by a neutralizing anti-CD44 mAb or by the pretreatment of aggrecan with chondroitinase, but not hyaluronidase or keratanase, indicating that CD44 binds aggrecan in a manner dependent on CS side chains of aggrecan and that hyaluronic acid is not involved in the binding. Structural analysis showed that glycosaminoglycans of aggrecan from rat chondrosarcoma and bovine articular cartilage consist of mainly CS A and a mixture of CS A and C respectively. When immobilized on microtiter plates, both CS A and C bound CD44–IgG, and the reaction was specifically inhibited by an anti-CD44 mAb. In addition, aggrecan augmented apoptosis in cells expressing CD44–Fas chimeric molecules in synergy with a non-blocking anti-CD44 mAb IRAWB14.4, suggesting that CD44–aggrecan interaction can induce oligomerization of the chimeric molecules. These results suggest that aggrecan interacts with CD44 to mediate cell adhesion and to trigger oligomerization of CD44 molecules, which may lead to intracellular signaling.

Keywords: aggrecan; CD44; chondroitin sulfate; extracellular matrix; proteoglycan; BCECF-AM 2′,7′-bis-(2-carboxyethyl)-5-(and-6)-carboxyfluorescein acetoxymethyl ester; CS chondroitin sulfate; HA hyaluronic acid; KS keratan sulfate; RA rheumatoid arthritis

Journal Article.  6527 words.  Illustrated.

Subjects: Immunology ; Biological Sciences

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content. subscribe or login to access all content.