Stem cell transplant
Stem cell transplantation is among the most established and widely used applications of blood-forming stem cells worldwide. For decades, stem cell transplants have been used to treat patients with serious blood disorders, immune deficiencies, and certain cancers. Today, thousands of stem cell transplantations are performed worldwide each year, making it a well-established part of modern medicine.
What is a stem cell transplant?
A stem cell transplant is a medical procedure in which healthy blood-forming stem cells are transferred to a patient to replace damaged, diseased, or destroyed cells.
Once transplanted, the stem cells migrate to the bone marrow, where they begin producing new blood cells and rebuilding the patient’s blood and immune system. This process can help restore the body’s ability to generate healthy red blood cells, white blood cells, and platelets.
Stem cell transplantation has been used in clinical medicine for more than five decades and is today an established treatment for a wide range of serious conditions. It is most commonly used in the treatment of blood cancers and disorders such as leukaemia, lymphoma, multiple myeloma, and myelodysplastic syndromes (MDS) 6.
Today, stem cell transplantation is performed in specialised hospitals around the world and remains one of the most important clinical applications of blood-forming stem cells. For many patients, both children and adults, it represents a potentially life-saving treatment and, in some cases, the only curative option available.
When is stem cell transplantation used?
Blood cancers
Used in the treatment of leukaemia, lymphoma, and multiple myeloma, where stem cells can help restore healthy blood production.
Inherited blood disorders
Applied in conditions such as thalassemia, sickle cell disease, and other inherited disorders affecting the blood and bone marrow.
Immune disorders
Used in selected immune deficiencies and bone marrow disorders where transplantation can help rebuild a functioning immune system.
Two different types of stem cell transplantation
Autologous transplantation
In an autologous transplant, the patient receives their own previously collected stem cells. This approach is commonly used in the treatment of certain cancers, including lymphoma, multiple myeloma, and selected solid tumors.
Because cord blood banking only became widely available in the early 2000s, most individuals with stored cord blood are still relatively young. Since the need for stem cell transplantation generally increases with age, the number of autologous cord blood transplantations may increase in the future as these individuals reach adulthood.
Allogeneic transplantation
In an allogeneic transplant, stem cells are donated by another person, either a family member or an unrelated donor. This type of transplantation is commonly used in the treatment of leukemia, inherited blood disorders, bone marrow failure syndromes, and certain immune system diseases.
The goal is to replace diseased or damaged blood-forming cells with healthy donor stem cells capable of rebuilding the patient’s blood and immune system. In some countries, allogeneic stem cell transplantation is also used as a treatment option for selected severe autoimmune conditions, including certain forms of multiple sclerosis (MS).
Sources of blood-forming stem cells
Blood-forming stem cells used in transplantation can be collected from three different sources.
Umbilical Cord Blood
Collected after delayed cord clamping from the umbilical cord and placenta, then processed and cryopreserved for potential future use.
Bone Marrow
Requires a compatible donor and collection through a specialised bone marrow procedure performed under anaesthesia.
Peripheral Blood
Typically collected from a compatible donor after several days of treatment to mobilise stem cells from the bone marrow into the bloodstream.
Why cord blood is unique
Cord blood has several characteristics that have made it an important source of blood-forming stem cells for transplantation.
One of its key advantages is that it can be collected, tested, and cryopreserved in advance. Unlike many other donor sources, cord blood is already available when needed.
For patients diagnosed with conditions such as acute leukemia, time can be critical. Searching for a suitable donor may take weeks, months or years, whereas stored cord blood can be retrieved, thawed, tested for viability, and prepared for transplantation within a much shorter timeframe 1.
Once transplanted, the stem cells migrate to the bone marrow where they begin producing new healthy blood cells and rebuilding the patient’s blood and immune system.
Cord blood has also been shown to require less stringent HLA matching than many traditional donor sources, which may increase the likelihood of finding a suitable transplant option for certain patients 2, 3.
In addition, studies have demonstrated a lower risk of severe graft-versus-host disease (GvHD) in some transplantation settings, while maintaining the therapeutic benefits of donor-derived stem cells 4.
Why clinicians value cord blood
Expanding the potential of cord blood transplantation
One historical limitation of cord blood transplantation has been the relatively low number of stem cells available in a single collection, which can be particularly challenging when treating larger children and adults.
To address this challenge, researchers have developed technologies that expand cord blood stem cells in the laboratory before transplantation. One example is Omisirge® (omidubicel), an ex vivo expanded cord blood product designed to increase the number of transplantable stem cells available from a single cord blood unit 4, 5.
Clinical studies have demonstrated faster neutrophil engraftment and encouraging outcomes in patients with serious blood and immune disorders when compared with conventional cord blood transplantation 4.
The approval of Omisirge represents an important milestone in transplantation medicine and highlights how innovation continues to expand the clinical potential of cord blood stem cells.
As new technologies become available, they may help improve access to transplantation and further strengthen the role of cord blood as an established source of stem cells for medical treatment.
Omisirge® at a glance
Why this matters
Stem cell transplantation remains one of the most established and important medical applications of blood-forming stem cells.
While no future medical need can be predicted, preserving stem cells at birth provides access to a unique biological resource that would otherwise be discarded.
As transplantation medicine continues to evolve, access to high-quality stem cell sources may become increasingly important for future patients and families.
When preserved cord blood becomes a treatment opportunity
Discover how eligible families may access specialised cord blood therapy programmes through Cellaviva’s international network.
References
- Eapen, M., Rubinstein, P., Zhang, M. J., Stevens, C., Kurtzberg, J., Scaradavou, A., Loberiza, F. R., Champlin, R. E., Klein, J. P., Horowitz, M. M., & Wagner, J. E. Outcomes of transplantation of unrelated donor umbilical cord blood and bone marrow in children with acute leukaemia. Lancet. 2007;369(9577):1947–1954. DOI:10.1016/S0140-6736(07)60915-5
- Eapen, M., Rocha, V., Sanz, G., Scaradavou, A., Zhang, M. J., Arcese, W., Sirvent, A., Champlin, R. E., O’Donnell, P. V., Passweg, J. R., Ballen, K. K., Horowitz, M. M., & Gluckman, E. Effect of graft source on unrelated donor haemopoietic stem-cell transplantation in adults with acute leukaemia: a retrospective analysis. Lancet Oncology. 2010;11(7):653–660. DOI:10.1016/S1470-2045(10)70127-3
- Milano, F., Appelbaum, F. R., & Delaney, C. Cord-Blood Transplantation in Patients with Minimal Residual Disease. New England Journal of Medicine. 2016;375(22):2204–2205. DOI:10.1056/NEJMc1612872
- Horwitz, M. E., Wease, S., Blackwell, B., Valcarcel, D., Frassoni, F., Boelens, J. J., et al. Omidubicel vs standard myeloablative umbilical cord blood transplantation: results of a phase 3 randomized study. Blood. 2021;138(16):1429–1440. DOI:10.1182/blood.2021011719
- Peled, T., Shoham, H., Aschengrau, D., Yackoubov, D., Frei, G., Rosenheimer, G. N., et al. Nicotinamide, a SIRT1 inhibitor, inhibits differentiation and facilitates expansion of hematopoietic progenitor cells with enhanced bone marrow homing and engraftment. Experimental Hematology. 2012;40(4):342–355.e1. DOI:10.1016/j.exphem.2011.12.005
- Snowden, J. A. et al. Indications for haematopoietic cell transplantation for haematological diseases, solid tumours and immune disorders: current practice in Europe, 2022. Bone Marrow Transplant 57, 1217-1239, doi:10.1038/s41409-022-01691-w (2022).