??The nice thing about cord blood is you don??t need to have the same degree of matching. Because the assumption in those cells from the cord are nave and were not exposed to any other antigens or any other proteins, that??s why they are less likely to cause complication in the recipient. So actually we don??t need a full match when you use cord blood.??
??With cord blood we learned the degree of match is only one of the factors, and the other factor is the number of cells in the cord blood bag. This is a given number, it??s not a number that we can manipulate or make any change to. That??s why we and others have started using it for only for small children. Because we knew that when you give it to somebody who is heavier, a heavier child or adult, it will not ??take.?? It will not do the job, it will not engraft; that??s the terminology. And that??s what led to the trial of different ways to make those stem cells from cord blood a little bit stronger. Some people try in the lab to make more of them, to expand their population and that??s more on an experimental level. And the other approach was to use more than one unit and initially the thought was just to give more cells. With time, it turns out, eventually only one takes over and that??s the interesting thing: we don??t know yet who will be the one that will take over; is it by number or is it by other genetic factors? What we do know is that when you give, one unit is serving as the major one and the other unit is more the supporting unit.??