RRC ID |
38736
|
著者 |
Kukita T, Kukita A, Nagata K, Maeda H, Kurisu K, Watanabe T, Iijima T.
|
タイトル |
Novel cell-surface Ag expressed on rat osteoclasts regulating the function of the calcitonin receptor.
|
ジャーナル |
J Immunol
|
Abstract |
Osteoclasts are known to be hematopoietic in origin. However, the detailed mechanisms of their differentiation and activation are not known. Cell-surface molecules preferentially expressed on cells of the osteoclast lineage may play some important roles in these processes. We prepared a mAb that recognizes a unique cell-surface membrane protein specifically expressed on rat osteoclasts. Expression of this Ag, designated as Kat1 Ag, was markedly stimulated by a factor secreted by the osteoblastic cell line ROS 17/2.8. Binding studies of 125I-labeled calcitonin (CT) showed that the Ag was not the CT receptor (CTR). However, interestingly, studies of the biologic activity of this mAb that recognizes Kat1-antigen (mAb Kat1) revealed possible regulatory functions of this Ag in osteoclasts. Firstly, mAb Kat1 significantly elevated the binding affinity of the CTR expressed on osteoclast-like cells without altering the number of receptors. Secondly, CT-sensitivity of the osteoclast progenitor cells in the system of osteoclast differentiation showed marked augmentation on treatment of these cells with this mAb. Even a very low concentration of CT (0.1 ng/ml) significantly inhibited osteoclast differentiation in the presence of mAb Kat1, whereas a higher concentration of CT (10 ng/ml) was required to inhibit their differentiation in the absence of this mAb. Thirdly, mAb Kat1 inhibited dentin-resorbing activity of osteoclast-like cells. Furthermore, the inhibitory effects of CT on osteoclast-mediated dentin resorption was augmented by the presence of this mAb. These observations strongly suggest that Kat1-antigen is a unique cell-surface protein regulating the affinity of the CTR expressed on osteoclasts and also the bone-resorbing function of these cells.
|
巻・号 |
153(11)
|
ページ |
5265-73
|
公開日 |
1994-12-1
|
PMID |
7963580
|
MeSH |
Animals
Antibodies, Monoclonal
Antigens, Surface / physiology*
Blotting, Western
Calcitonin / metabolism
Cells, Cultured
Dentin / metabolism
Osteoclasts / immunology*
Osteoclasts / physiology*
Osteoclasts / ultrastructure
Rats
Rats, Sprague-Dawley
Receptors, Calcitonin / physiology*
Tumor Cells, Cultured
|
IF |
4.886
|
引用数 |
23
|
WOS 分野
|
IMMUNOLOGY
|
リソース情報 |
ヒト・動物細胞 |
NRK(RCB0043)
Vero(RCB0001) |