Role of CX3CL1/CX3CR1 Signaling Axis Activity in Osteoporosis

Table 1

The potential role of the CX3CL1/CX3CR1 signaling axis in osteoclastogenesis. OCs: osteoclasts; OBs: osteoblasts; BMCs: bone marrow cells; CD: cluster of differentiation; CXCR4: CXC chemokine receptor type 4; BMD: bone mineral density; CSF1R: colony-stimulating factor 1 receptor; EGFP: enhanced green fluorescent protein; CX3CR1: CX3C chemokine receptor 1; LPA: lysophosphatidic acid; LPAR1: lysophosphatidic acid receptor type 1; BMMs: bone marrow macrophages; CX3CL1: CX3C motif chemokine ligand 1; PMOP: postmenopausal osteoporosis patients; PMNOP: healthy postmenopausal patients; TRACP-5b: tartrate-resistant acid phosphatase 5b; NTx: cross-linked N-telopeptides of type I collagen; IL-1β: interleukin 1 beta; IL-6: interleukin 6.

Study	Material	CX3CL1/CX3CR1 axis role
Koizumi et al.	(i) Mouse precursors of OCs (Toyama, Japan); (ii) Mouse OBs (Toyama, Japan); (iii) Mature OCs (Wako Pure Chemical); (iv) Bone samples of orthopedic patients (University of Toyama, Toyama, Japan)	(i) Stimulation of differentiation of OC precursors into mature OCs; (ii) Activation of local inflammatory reaction and migration of monocytes/macrophages to bone tissue; (iii) Cofactor for the OC maturation and OB binding
Goto et al.	(i) Mouse BMCs (CD45 CD11b^+, CD45^+ hematopoietic cells, CXCR4^+ CD45^-, Shizuoka, Japan)	(i) Promotion of osteoclastogenesis; (ii) Bone resorption and BMD reduction; (iii) Activation and fusion of OCs in the formation of multijugular forms
Kikuta et al.	(i) CD11b^+ cells from C57BL/6 mice (CREA Japan); (ii) BMCs from CSF1R-EGFP^+ transgenic mice (Jackson Laboratory); (iii) BMCs from CX3CR1-EGFP^+ knock-in mice (Jackson Laboratory); (iv) Mouse RAW264.7 cells (Chugai Pharmaceuticals Co., Ltd.)	(i) Stimulation of mobility of CX3CR1-EGFP^+ cells near bone tissue
David et al.	(i) BMCs from CX3CR1-EGFP^+ knock-in mice (Jackson Laboratory)	(i) Potential correlation with LPA/LPAR1 in promoting osteoclastogenesis process
Song et al.	(i) BMMs from C57BL/6 mice (CREA Japan)	(i) Induction of inflammatory processes and osteoclastogenesis
Chen et al.	Concentration of CX3CL1 in blood serum in group of; (i) 53 PMOP; (ii) 51 PMNOP; (iii) 50 healthy premenopausal patients	(i) Increasing the concentration of bone turnover markers (TRACP-5b, NTx) and inflammatory factors (IL-1β, IL-6) in blood serum; (ii) Potential marker and screening test of the exacerbation of osteoporotic lesions