Table 1. | Effects of cytokines on osteoclast cells [1,30,33] |
|
Cytokines (Effect on bone loss) |
Main producer cells |
Target cells in the regulation of OC |
Effects on OC |
|---|---|---|---|
| RANKL (↑) |
Stromal cells/OB; T cells |
OC precursor cells; OC |
OC generation ↑; OC activation; OC apoptosis ↓ |
| IL-1 (↑) | Macrophages | OB lineage cells |
OC generation ↑; OC activation |
| IL-4 (↓) |
Th2 cells; NK cells |
OC precursor cells |
OC generation ↓; RANK down-regulation |
| IL-6 (↑) |
Th2 cells; DCs |
Stromal cells/OB; T cells |
OC generation ↑; RANKL induction |
| IL-7 (↑) | Stromal cells |
OC precursor cells; T cells |
Indirect (T cell mediated mechanisms) |
| IL-10 (↓) | Th2 cells | OC precursor cells | RANK signalling inhibition |
| IL-12 (↓) |
Macrophages; DCs |
T cells | Indirect (via IFN-γ induction) |
| IL-17 (↑) | Th17 cells |
OC precursor cells; OB lineage cells |
OC generation ↑; RANKL induction |
| IL-18 (↓) |
Macrophages; DCs |
T cells | Indirect (via IFN-γ induction) |
| TNF-α (↑) |
Macrophages; Th1 cells; NK cells |
OC precursor cells; OB lineage cells |
Mobilization of OC precursors; RANKL induction; OC activation |
| INF-γ (γ↓↑) |
Th1 cells; NK cells |
OC precursor cells | Variable |
| M-CSF (↑) | Stromal cells/OB | OC precursor cells | OC survival and proliferation ↑ |
| GM-CSF (↓) |
Macrophages; T cells; NK cells |
OC precursor cells | RANKL signalling inhibition |
OC = osteoclasts; OB = osteoblasts; IL = interleukin; Th = T helper; RANK = receptor activator of nuclear factor κ B; RANKL = receptor activator of nuclear factor κ B ligand; NK = natural killer; DCs = dendritic cells; TNF-α = tumour necrosis factor alpha; INF-γ = interferon gamma; M-CSF = macrophage colony-stimulating factor; GM-CSF = granulocyte macrophage colony-stimulating factor. |