Title:‘Osteoimmunology' Offers New Perspectives for the Treatment of Pathological Bone Loss
Volume: 23
Issue: 41
Author(s): Hongrui Liu, Tingting Luo, Jiali Tan, Minqi Li and Jie Guo*
Affiliation:
- School of Stomatology Shandong University, Shandong Provincial Key Laboratory of Oral Tissue Regeneration, Jinan,China
Keywords:
Bone loss, osteoclast, osteoblast, osteoimmuology, T cells, B cells.
Abstract: New evidence of the interactions between the immune system and bone has accumulated in bone diseases,
including osteoporosis, periodontitis and rheumatoid arthritis. A marked imbalance between bone resorption
and formation is central to the onset of pathological bone loss. Osteoimmunology has revealed that the immune
system, including T cells, B cells and inflammatory cytokines, is a key regulator of both osteoclasts and
osteoblasts. Th1 cells, which differentiate from CD4+T cells, are thought to play a major function during bone
loss. Moreover, the correlated expression of Th1 cytokines (interleukin-12 (IL-12), interferon-γ (IFN-γ)) and
bone-resorbing cytokines (tumor necrosis factor-α (TNF-α), IL-1) also plays a key role during inflammatory
induced bone resorption. Furthermore, a relatively new member of the CD4+T cell family Th17 displays the ability
to promote osteoclast activity. The effect of IFN-γ and IL-17 released by Th 17 cells on pre-osteoclast proliferation,
differentiation and apoptosis provides the preliminary basis for the immune mechanism of pathological
bone loss. The role of B cells in osteoimmunological interactions has long been suspected based on findings of B
cells as active regulators of the RANK/RANKL/OPG axis. Pathological bone loss, including osteoporosis and
human immunodeficiency virus-associated bone loss, are related to the altered RANKL/OPG through modified
production by B cells, supporting this assumption. All of the above evidence may provide new theoretical explanations
for the relationship between bone metabolism and the immune system as well as offer perspectives for the
prevention and treatment of pathological bone loss.
