Since the transplantation of stem cells derived from umbilical cord blood was reported successful, a lot of interest has grown in the research, banking, as well as transplantation of CB stem cells. Cord blood transplantation helps to treat disorder like lymphoma, leukemia, aplastic anemia (AA), myelodyspasia, metabolic storage diseases, immune-deficiencies, and hemoglobinopathies. Blood banks have been created to help in the collection, processing, and cryopreserving of cord blood. The collection of cord blood is usually a painless and safe process. Neither the mother nor the baby is unsafe. It also does not interfere with the labor or delivery2.
Types of CB Collection
Generally speaking, there are 3 major types of cord blood collection and storage:
- Cord blood units collected and preserved for public use
- Cord blood units collected from a newborn and kept for the purpose of treating a family member who is known to suffer from an illness or disease treatable using hematopoietic stem cell transplantation (HSCT). This is also referred to as directed donor CB collection
- Cord blood units taken from a newborn and stored in blood banks for private use. This is in anticipation that the placental blood will someday be needed to help in providing treatment to a newborn (autologous use) or close family member (allogeneic use) who suffers a disease or ailment that is treatable using HSC transplantation.
How Cord Blood Is Collected?
Cord blood is collected at time of delivery when the baby is born. There are mainly two methods that are accepted to collect cord blood. 1
- Collection of blood immediately a baby is delivered before the placenta is separated from the uterus wall.
- The placenta and cord are taken from the delivery or operative field to an area where a specialist like phlebotomist or lab technician collects the cord blood. This is done after the cord and placenta are separated from the uterus wall by cutting.
Cord clamping and cutting
After the mother has delivered the baby, whether through a cesarean-section or vaginally, the umbilical cord is clamped and cut. The American College of Obstetrics and Gynecology (ACOG) says that it beneficial to the baby to delay clamping3 of the umbilical cord at time of delivery. The delay, if it happens, should be by 30 to seconds from the time of delivery to the time of cord clamping. This is for the healthy, full-term babies. However, when it comes to collection of cord blood, delaying clamping is likely to affect the quality of cells and volume of blood collected. 2
Extracting cord blood
To extract the CB, a medical provider inserts a needle right into the vein of the umbilical cord on the part joined to the placenta. This allows blood to drain into the collection bag. About 1 to 5 ounces of blood may be collected and the process takes a short time, probably less than 10 minutes. 2
Cord blood banking
After the collection, the specimen is taken to the cord blood bank. This involves shipping it to the CB bank for testing, processing, cryopreserving (controlled freezing, and storage. 2
Ensuring High Quality CB Units
In the collection of umbilical cord blood, it is important that high-quality units are obtained. The volume of blood collected should be maximized. It is also paramount that during collection all efforts and precautions are taken to avoid microbial contamination that could result in an infection at time of transplantation. Another thing is avoiding undue delays likely to cause the blood specimen to clot. Optimal cord blood processing, cryopreservation as well as storage are critical steps in ensuring that the CB unit obtained is safe and ensures potency of the graft.1
Cord Blood Processing
In the processing of CB units, sedimentation of red blood cells is done then followed by centrifugation involving leukocyte-rich plasma. The next step is to mix the centrifuged leukocyte-rich plasma with a cryopreservative solution. A controlled freezing is done prior to storing the cord blood using liquid nitrogen.1
In summary, the collection and storage of CB in public banks will continue to increase in the future. It is also possible that the expanded use of umbilical cord blood stored for family or personal use will increase. That being said, privately stored cord blood may not demonstrate a foreseeable future. It may just not be viable. Much of the cord blood banking will be intended for public donation.
Keywords: CB stem cells; Blood banks; cord blood; collect cord blood; cord blood bank; cord blood processing; use of umbilical cord blood
- Collection and Preservation of Cord Blood for Personal Use. https://www.sciencedirect.com/science/article/pii/S1083879107005745
- Cord blood banking: What it is, why consider it. https://www.babycenter.com/0_cord-blood-banking-what-it-is-why-consider-it_1362261.bc
- When To Clamp Umbilical Cord. https://parentsguidecordblood.org/en/news/when-clamp-umbilical-cord-full-term-babies