1. Attenuation of subchondral bone abnormal changes in osteoarthritis by inhibition of SDF-1 signaling 
Y. Chen, S. Lin, Y. Sun, J. Guo, Y. Lu, C.W. Suen, J. Zhang, Z. Zha, K.W. Ho, X. Pan, G. Li 
Osteoarthritis and Cartilage 
Volume 25, Issue 6, Pages (June 2017)
DOI: /j.joca
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

2. Fig. 1
(a) Gross appearance of tibial plateau of the samples obtained from patients at the time of total joint arthroplasty. On the OA part, the cartilage was severely fibrillated or damaged and from the more affected compartment; and on the RN part, the cartilage was RN or nonfibrillated which was from the uninvolved compartment. (b) Safranin-O/fast green and H&E staining of sagittal sections of the subchondral tibia in the OA and RN compartments of the same OA patient. Scale bar, 200 μm (in top), 50 μm (in bottom).
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

3. Fig. 2
(a) 3D μCT images of the tibia subchondral bone compartment of the OA (left) and RN (right) area from the same OA patient. Scale bar, 1 mm. Quantitative analysis of structural parameters of subchondral bone by μCT test. (b) BMD, (c) BV/TV. The results showed that subchondral bone had significantly higher BMD, BV/TV in the OA compartment compared to RN compartment. n = 5 per group. *P < 0.05: the OA compartment compared to the RN compartment.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

4. Fig. 3
(a) ELISA assay showed the SDF-1 level in subchondral bone in the severe OA part and the RN part from the same patient (n = 7). The result showed that SDF-1 in the severe OA part was significantly higher than that of the RN part. The statistical significance was determined by pair sample t-test. *P < 0.05: the OA part vs the RN part. (b)The phosphorylated (p) Erk1/2 and GAPDH in subchondral bone lysates were detected by Western blotting using appropriate antibodies. The result showed that pErk1/2 was up-regulated in OA side cartilage compared to the RN side.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

5. Fig. 4
Immunofluorescent staining showed that MSCs which were Nestin-positive (green) and CXCR4-positive (red). Their nuclei were stained by DAPI (blue). Scale bars, 25 μm.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

6. Fig. 5
SDF-1 plays an important role in MSCs osteogenic differentiation. (a) Blocking the SDF-1 signal reduced the ALP activity during MSCs osteogenic differentiation. MSCs were cultured in OIM or in normal culture medium as control. In parallel, cells were pretreated with AMD3100 at 400 μM for 2 h at 37°C prior to culture in OIM. The ALP staining assay in MSCs was detected at 5 days after cultured in OIM. The number of ALP positive cells (violet) were significantly reduced in the AMD3100 treated group compared to the OIM treated group. Scale bars, 200 μm. (b) Blocking SDF-1 signal inhibited intracellular Erk phosphorylation in MSCs osteogenic differentiation. The MSCs were pretreated with CXCR4 antagonist AMD3100 at 400 μM for 2 h at 37°C prior to culture in OIM for 15 min; the controls were cultured in normal culture media or OIM. Total Erk1/2, the phosphorylated (p) Erk1/2, and GAPDH were detected in cell lysates by Western blot. Level of phosphorylated (p) Erk1/2 was down-regulated in the AMD3100 treated group compared to the OIM group.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

7. Fig. 6
AMD3100 attenuates articular cartilage degeneration in ACLT + MMx rat. Safranin O and fast green staining of sagittal sections of the subchondral femora medial compartment in the AMD3100 treatment group, PBS group and OA group. Scale bar, 400 μm (in top), 200 μm (in bottom). The result showed that cartilage degeneration was less severe in the AMD3100 group, compared to the PBS or OA group.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

8. Fig. 7
AMD3100 reduces aberrant subchondral bone formation in a rat OA model. (a) 3D μCT images of the tibia subchondral bone compartment (sagittal view) of rats in the AMD3100 group, PBS group and OA group. Scale bar, 1 mm. Quantitative assay of structural parameters of subchondral bone by μCT. (b) BMD, (c) BV/TV. The results showed that subchondral bone had significantly reduce BMD, BV/TV in the AMD3100 treated group compared to PBS group or OA group. n = 5 per group. *P < 0.05: the AMD3100 group compared to the PBS or OA group.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions

9. Fig. 8
(a) Immunohistochemical analysis and quantification of Nestin (b) and Osterix (c) positive cells (brown) in the tibial subchondral region. The result showed that AMD3100 treatment would significantly reduced Nestin and Osterix positive cells compared to the other two groups. Scale bars, 50 μm. *P < 0.05, the AMD3100 group compared to the PBS or OA group.
Osteoarthritis and Cartilage  , DOI: ( /j.joca )
Copyright © 2017 Osteoarthritis Research Society International Terms and Conditions