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Updated: May 7, 2026
09:00
Isolation of Human Mesenchymal Stem Cells and their Cultivation on the Porous Bone Matrix
Published on: February 9, 2015
Direct resorption of bone by human monocytes.
Science (New York, N.Y.)
|June 3, 1977
Summary
Human monocytes can stimulate bone resorption in fetal rat bones, but this effect is blocked by cortisol. This suggests monocytes play a role in bone remodeling independent of typical osteoclast-stimulating hormones.
Area of Science:
- Immunology
- Bone Biology
- Cell Biology
Background:
- Monocytes are immune cells with diverse functions.
- Bone remodeling involves complex cellular interactions.
- Osteoclasts are key cells in bone resorption.
Purpose of the Study:
- To investigate the role of human peripheral blood monocytes in bone resorption.
- To determine if monocytes can directly stimulate bone mineral and matrix release.
- To examine the influence of cortisol and other hormones on monocyte-mediated bone resorption.
Main Methods:
- Cultured human peripheral blood monocytes were used.
- Killed long bones from fetal rats served as the bone model.
- Bone mineral and matrix release were measured.
- The effects of cortisol and osteoclast-stimulating hormones were assessed.
Main Results:
- Cultured human monocytes stimulated the release of bone mineral and matrix from fetal rat bones.
- Cortisol significantly inhibited this monocyte-induced bone resorption.
- Hormones known to stimulate osteoclastic bone resorption did not affect the monocyte-mediated process.
- No morphological differentiation of monocytes into osteoclasts was observed.
Conclusions:
- Human peripheral blood monocytes can induce bone resorption.
- This monocyte-driven bone resorption is sensitive to cortisol inhibition.
- The mechanism appears distinct from classical osteoclast-mediated resorption pathways.
- Monocytes may play a direct role in bone remodeling processes.
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