Human myeloma cells stimulate the receptor activator of nuclear factor-κB ligand (RANKL) in T lymphocytes: a potential role in multiple myeloma bone disease
Blood, The Journal of the American Society of Hematology, 2002•ashpublications.org
The biologic mechanisms involved in the pathogenesis of multiple myeloma (MM) bone
disease are not completely understood. Recent evidence suggests that T cells may regulate
bone resorption through the cross-talk between the critical osteoclastogenetic factor,
receptor activator of nuclear factor-κB ligand (RANKL), and interferon γ (IFN-γ) that strongly
suppresses osteoclastogenesis. Using a coculture transwell system we found that human
myeloma cell lines (HMCLs) increased the expression and secretion of RANKL in activated …
disease are not completely understood. Recent evidence suggests that T cells may regulate
bone resorption through the cross-talk between the critical osteoclastogenetic factor,
receptor activator of nuclear factor-κB ligand (RANKL), and interferon γ (IFN-γ) that strongly
suppresses osteoclastogenesis. Using a coculture transwell system we found that human
myeloma cell lines (HMCLs) increased the expression and secretion of RANKL in activated …
The biologic mechanisms involved in the pathogenesis of multiple myeloma (MM) bone disease are not completely understood. Recent evidence suggests that T cells may regulate bone resorption through the cross-talk between the critical osteoclastogenetic factor, receptor activator of nuclear factor-κB ligand (RANKL), and interferon γ (IFN-γ) that strongly suppresses osteoclastogenesis. Using a coculture transwell system we found that human myeloma cell lines (HMCLs) increased the expression and secretion of RANKL in activated T lymphocytes and similarly purified MM cells stimulated RANKL production in autologous T lymphocytes. In addition, either anti–interleukin 6 (anti–IL-6) or anti–IL-7 antibody inhibited HMCL-induced RANKL overexpression. Consistently, we demonstrated that HMCLs and fresh MM cells express IL-7 mRNA and secrete IL-7 in the presence of IL-6 and that bone marrow (BM) IL-7 levels were significantly higher in patients with MM. Moreover, we found that the release of IFN-γ by T lymphocytes was reduced in presence of both HMCLs and purified MM cells. Furthermore, in a stromal cell–free system, osteoclastogenesis was stimulated by conditioned medium of T cells cocultured with HMCLs and inhibited by recombinant human osteoprotegerin (OPG; 100 ng/mL to 1 μg/mL). Finally, RANKL mRNA was up-regulated in BM T lymphocytes of MM patients with severe osteolytic lesions, suggesting that T cells could be involved at least in part in MM-induced osteolysis through the RANKL overexpression.
ashpublications.org