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)