Immunoreactivity and proliferative actions of beta 2 microglobulin on human bone-derived cells in vitro.
Recent studies have demonstrated homology between bone-derived growth factor and beta 2 microglobulin. We have shown that beta 2 microglobulin has proliferative actions on human bone-derived cells in vitro and that these cells also show immunogenicity for beta 2 microglobulin. beta 2 microglobulin stimulated the incorporation of 3H-thymidine into DNA of human bone cells in a dose-dependent manner. In contrast to this stimulatory action, beta 2 microglobulin had no detectable activity with the same concentration on the production of osteocalcin, alkaline phosphatase activity or prostaglandin E2 synthesis. The possibility that the human bone-derived cells could also produce beta 2 microglobulin was examined. Under basal conditions these cells exhibit immunoreactivity for beta 2 microglobulin, the expression of which could be enhanced following treatment with interferon gamma in a dose-dependent manner. The co-localization of staining for beta 2 microglobulin and alkaline phosphatase, a marker of the osteoblast phenotype, indicate that human osteoblast-like cells represent a source of activity of this factor. The production of beta 2 microglobulin by human osteoblast-like cells and the subsequent action of this factor on cells within the bone microenvironment may indicate a role for beta 2 microglobulin as a local regulator of bone metabolism.
Evans
D B
DB
Department of Human Metabolism and Clinical Biochemistry, University of Sheffield Medical School, UK.
Thavarajah
M
M
Kanis
J A
JA
D000469:Alkaline Phosphatase / Q000378:metabolism; D001842:Bone and Bones / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004261:DNA Replication / Q000187:drug effects; D015232:Dinoprostone / Q000378:metabolism; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007700:Kinetics; D010006:Osteoblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D015675:Osteocalcin / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D011994:Recombinant Proteins; D001613:beta 2-Microglobulin / Q000032:analysis / Q000494:pharmacology* / Q000502:physiology
D011506:Proteins; D011994:Recombinant Proteins; D001613:beta 2-Microglobulin; D015675:Osteocalcin; D007371:Interferon-gamma; D000469:Alkaline Phosphatase; D015232:Dinoprostone