Fig 1: CSSEDF-expanded cells stably self-renewed and shared markers of CPCs/CSCs.a A single CSSEDF-expanded cell (passage 5) colony on a Matrigel-coated surface. Scale bars, 50 µm. b–d Immunocytochemistry showing that CSSEDF-expanded cells expressed genes identified as neural ectodermal markers, including SIX1, NESTIN and ETS1. Scale bars, 50 µm. e–i Immunocytochemistry showing that CSSEDF-expanded cells (passage 5) expressed genes identified as CPC/CSC markers, including SOX9, RUNX2, SOX5, TWIST1, and CD29. Scale bars, 50 µm. j–l Immunocytochemistry showing that CSSEDF-expanded cells (passage 5) express genes recently identified as TMJ condylar cartilage markers, including FOXC1, FOXC2 and MSX1. Scale bars, 50 µm. m Flow cytometry analysis showing that CSSEDF-expanded cells stably express cell proliferation and CPC/CSC markers after long-term in vitro expansion. n Gene expression of chondrocytic lineage markers by CSSEDF-expanded cells at different passages and patient TMJ condylar cartilage were analysed by PCR. CPCs/CSCs: cartilaginous progenitor cells/cartilaginous stem cells.