(A) HA-VSMCs, THP-1 cells, co-cultured HA-VSMCs (bottom chamber) with THP-1 cells (upper chamber), and co-cultured HA-VSMCs (bottom chamber) with ox-LDL-treated THP-1 cells (upper chamber) were seeded into Transwell plates and incubated for 24 or 48 h. The upper chamber was then removed and cell proliferation was detected with the MTT assay. (B) Cells were treated as in (A); after 48 h, the upper chamber was removed and the HA-VSMCs were fixed and stained with Oil Red O. The respective images are shown (×200). (C) Cells were treated as in (A); after 48 h, the upper chamber was removed, the culture medium in the bottom chamber was collected, and CXCL12 expression was examined by ELISA. (D) Cells were collected and lysed with lysis buffer, and Western blotting was performed. **, P<0.05, HA-VSMC+THP-1 s. HA-VSMC+THP-1+ox-LDL; ***, P<0.001, HA-VSMCs+THP-1 vs. HA-VSMCs+THP-1+ox-LDLs.