TY - JOUR
T1 - Neutralization of CD40 ligand costimulation promotes bone formation and accretion of vertebral bone mass in mice
AU - Roser-Page, Susanne
AU - Vikulina, Tatyana
AU - Yu, Kanglun
AU - McGee-Lawrence, Meghan E.
AU - Weitzmann, M. Neale
N1 - Publisher Copyright:
© The Author(s) 2018. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved.
PY - 2018/6/1
Y1 - 2018/6/1
N2 - Objective. Immunosuppressive biologics are used in the management of RA and additional immunomodulators are under investigation including modulators of the CD40/CD40 ligand (CD40L) costimulation pathway. Tampering with immune function can have unanticipated skeletal consequences due to disruption of the immuno-skeletal interface, a nexus of shared cells and cytokine effectors serving discrete functions in both immune and skeletal systems. In this study, we examined the effect of MR1, a CD40L neutralizing antibody, on physiological bone remodelling in healthy mice. Methods. Female C57BL6 mice were treated with MR1 and BMD was quantified by dual energy X-ray absorptiometry and indices of trabecular bone structure were quantified by micro-CT. Serum biochemical markers were used to evaluate bone turnover and formation indices by histomorphometry. Results. Unexpectedly, MR1 stimulated significant accretion of BMD and trabecular bone mass in the spine, but not in long bones. Surprisingly, bone accretion was accompanied by a significant increase in bone formation, rather than suppression of bone resorption. Mechanistically, MR1-induced bone accrual was associated with increased Treg development and elevated production of cytotoxic T lymphocyte antigen 4, a costimulation inhibitor that promotes T cell anergy and CD8+ T cell expression of the bone anabolic ligand Wnt-10b. Conclusion. Our studies reveal an unexpected bone anabolic activity of pharmacological CD40L suppression. Therapeutic targeting of the CD40L pathway may indeed have unforeseen consequences for the skeleton, but may also constitute a novel strategy to promote bone formation to ameliorate osteoporotic bone loss and reduce fracture risk in the axial skeleton.
AB - Objective. Immunosuppressive biologics are used in the management of RA and additional immunomodulators are under investigation including modulators of the CD40/CD40 ligand (CD40L) costimulation pathway. Tampering with immune function can have unanticipated skeletal consequences due to disruption of the immuno-skeletal interface, a nexus of shared cells and cytokine effectors serving discrete functions in both immune and skeletal systems. In this study, we examined the effect of MR1, a CD40L neutralizing antibody, on physiological bone remodelling in healthy mice. Methods. Female C57BL6 mice were treated with MR1 and BMD was quantified by dual energy X-ray absorptiometry and indices of trabecular bone structure were quantified by micro-CT. Serum biochemical markers were used to evaluate bone turnover and formation indices by histomorphometry. Results. Unexpectedly, MR1 stimulated significant accretion of BMD and trabecular bone mass in the spine, but not in long bones. Surprisingly, bone accretion was accompanied by a significant increase in bone formation, rather than suppression of bone resorption. Mechanistically, MR1-induced bone accrual was associated with increased Treg development and elevated production of cytotoxic T lymphocyte antigen 4, a costimulation inhibitor that promotes T cell anergy and CD8+ T cell expression of the bone anabolic ligand Wnt-10b. Conclusion. Our studies reveal an unexpected bone anabolic activity of pharmacological CD40L suppression. Therapeutic targeting of the CD40L pathway may indeed have unforeseen consequences for the skeleton, but may also constitute a novel strategy to promote bone formation to ameliorate osteoporotic bone loss and reduce fracture risk in the axial skeleton.
KW - Bone formation
KW - CD40 ligand
KW - MR1
KW - Osteoblast
KW - Rheumatoid arthritis
KW - T cell
KW - Wnt-10b
UR - http://www.scopus.com/inward/record.url?scp=85048555622&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85048555622&partnerID=8YFLogxK
U2 - 10.1093/rheumatology/kex525
DO - 10.1093/rheumatology/kex525
M3 - Article
C2 - 29522194
AN - SCOPUS:85048555622
SN - 1462-0324
VL - 57
SP - 1105
EP - 1114
JO - Rheumatology (United Kingdom)
JF - Rheumatology (United Kingdom)
IS - 6
ER -