We recommend seeding these cells at densities ranging from 2 x 10E4 to 5.5 x 10E4 cells/cm2. A good starting point is 3 x 10E4 cells/cm2. If the feeder cells are too sparse, they may not maintain the pluripotent cells without differentiation, and the pluripotent cells may not attach well. If the feeder cells are too dense, the feeder layer may detach from the plate, and the culture will be lost.