Interleukin-7 Influences Osteoclast Function In Vivo but Is Not a Critical Factor in Ovariectomy-Induced Bone Loss

Abstract

IL-7 is produced by stromal cells in bone marrow and is a major regulator of B and T lymphopoiesis. It is also a direct inhibitor of osteoclastogenesis in vitro. In this study we show that IL-7-deficient mice have increased OC and decreased trabecular bone volume compared with WT mice but mimic WT mice in the amount of trabecular but not cortical bone lost after ovariectomy.

miR-29 Promotes Murine Osteoclastogenesis by Regulating Osteoclast Commitment and Migration

“…The primary cultures obtained from bone marrow are heterogeneous, even when depleted of lymphocytes (33). For this reason, we sought a more simplified and homogeneous model system for the purpose of evaluating the mechanisms by which miR-29 regulates osteoclast differentiation.…”

Selective inhibition of RANK blocks osteoclast maturation and function and prevents bone loss in mice

“…We continued the treatment at 4-day intervals for 28 days and terminated the experiment on day 31. Histology and μCT imaging were carried out essentially as previously described (56,57).…”

Increased bone resorption and osteopenia are a part of the lymphoproliferative phenotype of mice with systemic over-expression of interleukin-7 gene driven by MHC class II promoter

“…In vitro, IL-7 had inhibitory effect on both osteoclasts (OCL) [4] and osteoblasts (OBL) [6]. In vivo, young female transgenic mice expressing human IL-7 gene selectively in OBLs showed increased numbers of early B lymphocytes in the BM and increased trabecular bone mass [7,8]. Mice expressing an IL-7 transgene driven by MHC class II (E α ) promoter [3] develop enlarged marrow cavity and focal osteolysis related to the lymphoproliferative phenotype [9].…”