| STUDY ON THE REGULATION OF OSTEOCLAST AND T CELL ACTIVATION VIA CELL MEMBRANE PROTEINS OF TNF FAMILY, CD137 LIGAND AND RANK LIGAND |
|
Sung-Joon Hong1, Jae-Hong Park1, Hyeon-Woo Lee2, Keung-Ho Lee1 |
1Department of Pediatric Dentistry, School of Dentistry, Kyung Hee University
2Department of Phamacology and Institute of Oral Biology, School of Dentistry, Kyung Hee University |
| TNF계 CD137L 및 RANKL의 파골세포와 T 세포에 대한 활성조절 |
|
홍성준1, 박재홍1, 이현우2, 이긍호1 |
1경희대학교 치과대학 소아치과학교실
2경희대학교 치과대학 치과약리학교실, 구강생물학 연구소 |
Correspondence:
Jae-Hong Park, Tel: 02-958-9373, Email: pedopjh@khu.ac.kr
|
|
Received: 18 April 2008 • Accepted: 8 July 2008 |
|
|
| Abstract |
|
Resorption of alveolar bone in periodontitis is due to excessive differentiation and activation of osteoclasts. Bacterial antigens causing periodontitis activates CD4 T cells, which leads to expressing RANK ligand (RANKL) on CD4 T cells. RANKL binds RANK on preosteoclasts or osteoclasts, and enhances the differentiation preosteoclasts into osteoclasts and the activation of mature osteoclasts. CD137, one of TNF receptor (TNFR) family, expressed on activated T cells binds with CD137 ligand (CD137L) on antigen presenting cells. Cross-linking of CD137 by CD137L acts as T cell co-stimulatory signals and, therefore, enhances the activation of T cell. In this study, I elucidated the biological responses of CD137L on (pre)osteoclasts and RANKL on T cells in the context of in vivo interaction between T cells and osteoclasts. RAW264.7, murine monocytic cells, constitutively express CD137L. Ligation of CD137L with anti-CD137L mAb inhibited RANKL-induced osteoclast formation in a dosedependent manner. Bone marrow cells are expressed CD137L by the treatment with M-CSF. Cross-linking of CD137L abolished M-CSF/ RANKL-evoked the formation of multi-nucleated osteoclasts. Both mouse CD4 and CD8 T cells are expressed RANKL following their activation. Ligation of RANKL with OPG, the decoy receptor for RANKL, inhibited both CD4 and CD8 T cell proliferation. These effects were attributed to RANKL-induced apoptosis. These data indicate that CD137L and RANKL on osteoclasts and T cells, respectively provide them with inhibitory signal. |
| Key Words:
RANKL, CD137L, Osteoclast, T lymphocyte |
|
PDF Links
Download Citation
