Ann: DREAM HF Trial Published in JACC, page-108

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There are many advantages of UCB as a source of Human Stem Cells (HSCs) as compared to BM and Peripheral Blood (PB). First, the collection of cord blood units is easy and non-invasive for the donor and therefore the number of potential donors is higher than for bone marrow. Umbilical cord can be easily obtained without causing pain, and the procedure avoids ethical and technical issues [58]. Then, cord blood units are stored in advance and are therefore rapidly available when needed while bone marrow has to be collected from the donor just before transplantation and there is always a risk of last minute consent refusal. Moreover, MSCs from UCB are more primitive than MSCs isolated from some other tissue sources [60-63]. Despite, reports to date have focused on obtaining those cells after culture expansion from a segment of the umbilical cord [64-66]. Culture expansion has a disadvantage, the cells cannot be frozen on the same day as UCB cells arrive in the laboratory, and there is the increased risk of contamination with any culture manipulation. Moreover, MSCs from UCB have lower success rate of isolating if compared with MSCs from BM (63% vs 100%) [67].