An innovative method of collecting cord blood stem cells from an isolated mammalian non-exsanguinated or partially exsanguinated placenta by placental perfusion is described and also an easy method for safe long duration cold storage of the placenta. Placental perfusion can include perfusing the isolated placenta with a pulsatile flow of perfusion solution, for example, using a pulsatile or peristaltic pump or device. The stem cells can then be isolated from the perfusate. Significantly increased amounts of CD133+ stem cells can be collected from the perfusate. The perfusion solution can include an anticoagulant. The isolated mammalian placenta need not be treated with an anticoagulant prior to perfusing. The isolated placenta can be free from an anticoagulant prior to perfusing.
