Culturing Cell Lines and Primary Cells

HeLa, HaCaT, and HEK293T cell lines (ATCC) were maintained at 37°C in a humidified atmosphere of 5% CO₂ in fully supplemented media containing DMEM with 10% fetal bovine serum (FBS), nonessential amino acids, sodium pyruvate (Thermo Fisher Scientific), and Mycozap-CL (Lonza). Primary cardiac fibroblasts were isolated from neonatal mouse hearts as described (Zhang et al., 2014 (link)). Fibroblasts adhering to the dish during the pre-plating step were enriched for 1 week in DMEM:F12 supplemented with 3.5% FBS and 1x Mycozap-PR (Lonza). Primary glial cells were isolated from neonatal mouse brains as previously described (He et al., 2007 (link); Habas et al., 2013 (link)).