CA1S are a subline of embryonic stem cells (ESCs) derived from the parental CA1 line using the single-cell passaging adaptation procedure. These cells are relatively insensitive to enzymatic dissociation and can be maintained for months in this state. The cells express standard markers of pluripotent human ESCs, produce typical well-differentiated multi-lineage teratomas in vivo, and retain the ability to differentiate into cells of the three germ layers in vitro and in vivo. When differentiated into definitive endoderm these cells do not require WNT3A treatment.
Cells are maintained on Matrigel-coated dishes in mTeSR1 or mouse embryonic fibroblast-conditioned medium (MEF-CM) containing DMEM/F12, supplemented with Knockout serum replacement (20%), non-essential amino acids (0.1 mM), GlutaMAX (2 mM), Penicillin-Streptomycin (100 units/ml), β-mercaptoethanol (10-4 M) and basic fibroblast growth factor (bFGF; 4 ng/ml). Cells are passaged every 4 to 5 days after enzymatic dissociation with TrypLE Express or Accutase.