Cord blood

Cord blood (umbilical cord blood) is blood that remains in the placenta and in the attached umbilical cord after childbirth. Cord blood is collected because it contains stem cells, which can be used to treat hematopoietic and genetic disorders. Cord blood (umbilical cord blood) is blood that remains in the placenta and in the attached umbilical cord after childbirth. Cord blood is collected because it contains stem cells, which can be used to treat hematopoietic and genetic disorders. Cord blood is composed of all the elements found in whole blood - red blood cells, white blood cells, plasma, platelets. Compared to whole blood some differences in the blood composition exist, for example, cord blood contains higher numbers of natural killer cells, lower absolute number of T-cells and a higher proportion of immature T-cells. However, the interest in cord blood is mostly driven by the observation that cord blood also contains various types of stem and progenitor cells, mostly hematopoietic stem cells. Some non-hematopoietic stem cell types are also present in cord blood, for example, mesenchymal stem cells, however these are present in much lower numbers that can be found in adult bone marrow. Endothelial progenitor cells and multipotent unrestricted adult stem cells can also be found in cord blood. The stem cells found in cord blood are often confused with embryonic stem cells - unlike embryonic stem cells, cord blood stem cells are all types of adult stem cells, are lineage restricted and are not pluripotent. Cord blood is used the same way that hematopoietic stem cell transplantation is used to reconstitute bone marrow following radiation treatment for various blood cancers, and for various forms of anemia. Its efficacy is similar as well. Adverse effects are similar to hematopoietic stem cell transplantation, namely graft-versus-host disease if the cord blood is from a genetically different person, and the risk of severe infection while the immune system is reconstituted. To assure that the smallest amount of complications occur during transplantation, levels of engraftment must be present; specifically both neutrophils and platelets must be being produced. This process of neutrophil and platelet production after the transplant, however, takes much longer than that of stem cells. In many cases, the engraftment time depends on the cell dose, or the amount of stem cells obtained in the sample of blood. In Dr. Moise’s article about umbilical cord blood (as cited in ), it was found that there is approximately 10% less stem cells in cord blood than there is in bone marrow. Therefore a sufficient amount of cord blood must be obtained in order to collect an adequate cell dose, however this amount varies from infant to infant and is irreplaceable. Given that this idea is quite new, there is still a lot of research that needs to be completed. For example, it is still unknown how long cord blood can safely be frozen without losing its beneficial effects. There is a lower incidence with cord blood compared with traditional HSCT, despite less stringent HLA match requirements. Umbilical cord blood is the blood left over in the placenta and in the umbilical cord after the birth of the baby. There are several methods for collecting cord blood. The method most commonly used in clinical practice is the 'closed technique', which is similar to standard blood collection techniques. With this method, the technician cannulates the vein of the severed umbilical cord using a needle that is connected to a blood bag, and cord blood flows through the needle into the bag. On average, the closed technique enables collection of about 75 ml of cord blood. Collected cord blood is cryopreserved and then stored in a cord blood bank for future transplantation. Cord blood collection is typically depleted of red blood cells before cryopreservation to ensure high rates of stem cell recovery. The first successful cord blood transplant (CBT) was done in 1988 in a child with Fanconi anemia. Early efforts to use CBT in adults led to mortality rates of about 50%, due somewhat to the procedure being done in very sick people, but perhaps also due to slow development of immune cells from the transplant. By 2013, 30,000 CBT procedures had been performed and banks held about 600,000 units of cord blood. The AABB has generated accreditation standards for cord blood banking facilities.