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Updated: May 28, 2026
09:37
A RANKL-based Osteoclast Culture Assay of Mouse Bone Marrow to Investigate the Role of mTORC1 in Osteoclast Formation
Published on: March 15, 2018
Primary human bone marrow adipocytes support TNF-α-induced osteoclast differentiation and function through RANKL
Hisataka Goto1, Akira Hozumi, Makoto Osaki
1Department of Orthopaedic Surgery, Graduate School of Biomedical Science, Nagasaki University School of Medicine, 1-7-1 Sakamoto, Nagasaki 852-8501, Japan.
Cytokine
|October 4, 2011
Summary
Tumor necrosis factor-alpha (TNF-α) boosts Receptor Activator of Nuclear factor κ-B Ligand (RANKL) in bone marrow cells. This enhances osteoclast differentiation, potentially impacting osteoporosis.
Area of Science:
- Bone Biology
- Cellular Biology
- Immunology
Background:
- Bone marrow adipocytes are implicated in steroid osteoporosis via Receptor Activator of Nuclear factor κ-B Ligand (RANKL) induced osteoclastogenesis.
- Understanding the role of inflammatory cytokines in this process is crucial for developing targeted therapies.
Purpose of the Study:
- To investigate the effect of Tumor necrosis factor-alpha (TNF-α) on RANKL expression in human bone marrow adipocytes.
- To evaluate the capacity of TNF-α-treated bone marrow adipocytes to support osteoclast differentiation.
Main Methods:
- Real-time RT-PCR was used to quantify mRNA expression of RANKL, osteoprotegerin (OPG), and macrophage-colony stimulating factor (M-CSF) in bone marrow adipocytes.
- Co-culture systems of bone marrow adipocytes and osteoclast precursors were established with or without TNF-α to assess osteoclast differentiation morphologically and functionally.
Main Results:
- TNF-α treatment significantly increased RANKL expression and the RANKL/OPG ratio in bone marrow adipocytes.
- Co-cultures with TNF-α showed increased TRAP-positive multinuclear cells and resorption activity, indicating enhanced osteoclast differentiation.
- Osteoclast differentiation was inhibited by anti-RANKL antibody, confirming the mechanism's dependence on RANKL.
Conclusions:
- TNF-α upregulates RANKL expression in primary human bone marrow adipocytes.
- Bone marrow adipocytes treated with TNF-α promote osteoclast differentiation and activity, mediated by increased RANKL expression.
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