The first stem cell transplants were performed with blood stem cells in the 60's, researchers quickly realized its potential for regenerative medicine.
The difference between stem cells in cord tissue and cord blood.
It's important to note that umbilical cord blood and cord tissue are rich in two distinct types of stem cells. Both types of stem cells play key roles in regenerative medicine, and each works in its own way.
The blood within your baby's umbilical cord that remains in the umbilical cord and placenta after delivery, is called 'cord blood' for short. The umbilical cord contains the same powerful stem cells that help your baby develop organs, blood, tissue, and an immune system during pregnancy. After your baby is born, whether vaginally or by c-section, the cord is clamped and then cut according to the maternity clinic’s usual procedure – either by your partner or your midwife. There is still blood left over in the umbilical cord that can be collected and saved even after delayed cord clamping.
Hematopoietic stem cells (HSC) give rise to all blood cells. They were discovered in 1961 and the main source of hematopoietic stem cells is bone marrow and umbilical cord blood. Around 50 000 patients receive a stem cell transplantation each year, a therapy given to treat a number of deadly diseases including leukemia, lymphoma, metabolic diseases and immune system diseases.
Every part of the human body contains some stem cells, but most are not a rich enough source to be harvested for therapeutic applications. Hematopoietic stem cells can be found in bone marrow, cord blood and in smaller numbers in peripheral blood. Unlike the stem cells in bone marrow or peripheral blood, stem cells in cord blood are immature and have not yet learned how to attack foreign substances. In addition to their relative potency, when used in treatment, cord blood stem cells are less likely to cause problems in transplant because of their youth and flexibility. The properties of cord blood cells mean they can more easily integrate into a patient’s body. It's easier to match transplant patients with cord blood than with other sources of stem cells. This makes cord blood an even more valuable resource for ethnic minorities, who have a harder time finding stem cell matches in the registry of adult bone marrow donors.
Cord blood is currently used in the treatment of more than 80 diseases and has been determined to be the preferred source of stem cells for a transplant: Cord blood can be used in partial matches and shows a reduced risk of transplantation complications. In addition, when someone contracts a disease that must be treated with chemotherapy or radiation, there is a high probability of a negative impact on the immune system. Hematopoietic stem cells found in cord blood are used to bolster and re-populate the cells in the blood and immune system. Leukemia is a disease where chemotherapy is often used to rid the body of the cancerous blood cells, but it takes its toll on the body’s normal blood-forming cells, too. Stem cell transplants infuse the body with the blood-forming cells it needs to recover, effectively replacing the old cells with new, healthy cells.
If the treatment is more beneficial with the body’s own stem cells or from a donor depends on the illness or condition being treated. When doctors use stem cells to help the body repair itself, the patient's own cells are ideal. There's no concern that the body will reject its own stem cells or react against them. But when the body is making altered cells – for example, if the illness is cancer or a genetic blood disorder – then the transplant must come from another donor, not the patient's own cells. That's because the patient's stem cells will carry the same defect that caused the genetic disease, and sometimes changes predisposing for the cancer, and you'd be transplanting the seeds of the disease back into the patient. In leukemia there is often the need for the transplanted cells to attack the tumor cells, and for this another donor, such as a sibling, is the best choice. A family member with matching HLA will always be the preferable choice for donation for a genetic disease. Your baby’s umbilical cord stem cells are a perfect match for your child and are more likely to be a match for siblings. A family saving of stem cells is therefor a safety for your entire family and not only for the child the stem cells belong to.
Beyond the current treatments, the possible uses of cord blood have not been completely defined, and clinical trials are underway for its use as a regenerative therapy in strokes, heart disease, diabetes and many more.