Isolation and Culture of Murine Cell Lines

HEK293T and C3H10T1/2 cells (RIKEN, Ibaraki, Japan) were cultured in Dulbecco’s modified Eagle’s medium (DMEM) (Wako Pure Chemical Industries, Osaka, Japan) supplemented with 10% fetal bovine serum (FBS) (Nichirei Biosciences, Tokyo, Japan) and penicillin–streptomycin-glutamine (Wako Pure Chemical Industries). Articular cartilage SFZ cells were isolated as described previously^{26 (link),42 (link)}. SFZ cells were maintained in DMEM containing 10% FBS and penicillin–streptomycin-glutamine. Costal chondrocytes were isolated from ribs of 4-day-old mice by digestion with collagenase. The chondrocytes were collected from dispersions and cultured in DMEM supplemented with 10% FBS and penicillin–streptomycin-glutamine. LB cells were isolated from LB of E11.5 embryos by digestion with trypsin and collagenase. The LB cells were collected from dispersions and cultured in DMEM supplemented with 10% FBS and penicillin–streptomycin-glutamine.