HealthWACH: Umbilical cord implants
Wed, 18 Jun 2014 02:00:00 GMT — COLUMBIA (WACH) - Originally the source of transplant was from the bone marrow of a matched sibling. From somebody within the family who has the same tissue type and thatâ??s what we called HLA matched, but, obviously only one-third of patients will have that option available to them. So, researchers started looking at other sources and the next was an unrelated donor, adult unrelated donor transplant. The unrelated donor transplant was very successful in their finding, and what is connected with that as well is the understanding and the better tissue typing that improved so that the matching can be much improved and prevent complications. Still the unrelated registry is limited because of the variability or the changes were all different especially in the United States where the population is so heterogeneous. And small minorities and ethnic groups did not have the right to enough representation in that. So next was what was found is cord blood; in other words, the area that is discarded placenta. The cord blood contained blood from the baby thatâ??s not going to be used and that also contains the same hematopoietic stem cells, in other words blood stem cells, that can populate or that can build a new bone marrow.
â??The nice thing about cord blood is you donâ??t need to have the same degree of matching. Because the assumption in those cells from the cord are naÃ¯ve and were not exposed to any other antigens or any other proteins, thatâ??s why they are less likely to cause complication in the recipient. So actually we donâ??t need a full match when you use cord blood.â??
â??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, itâ??s not a number that we can manipulate or make any change to. Thatâ??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 â??take.â?? It will not do the job, it will not engraft; thatâ??s the terminology. And thatâ??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 thatâ??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 thatâ??s the interesting thing: we donâ??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.â??