Exciting Advancements in Cord Blood Treatments for Sickle Cell Anemia

September is National Sickle Cell Awareness Month, a key time to highlight how cord blood banking can make a lasting difference in the fight against this disease.

A short primer on sickle cell disease

Sickle cell disease (SCD) is an inherited genetic blood disorder passed from parents to children. A baby is born with sickle cell disease when they inherit two abnormal hemoglobin genes, one from each parent. A baby who inherits only one abnormal gene from one parent is a carrier with sickle cell trait. If that baby grows up to have a child with another carrier, then their baby has a chance of inheriting sickle cell disease.

For many families, these genetic facts translate into real-life journeys toward recovery.

Complications of sickle cell disease

The sickle cell genes cause episodes where the body’s red blood cells become rigid, inflexible and mis-shaped, changing from a disk shape to a curved shape that looks like a crescent moon or an old farm tool known as a sickle. These “sickle” cells tend to stick together and block the flow of blood and oxygen to the body, causing pain in the extremities and back, infections in the skin and other areas, organ failure and other tissue damage, loss of eyesight, severe blood clots and strokes. These complications tend to progress at adolescence and worsen during early adulthood and often lead to early mortality.

In addition, the sickle-shaped blood cells don’t last as long as they do in healthy people (10–20 days as opposed to 120 days). The bone marrow can’t replace these blood cells fast enough, which causes anemia.

Sickle cell can also lead to infections in the spleen. As the spleen filters the blood of infections, it can filter out the sickle-cell shaped red blood cells. This can cause the spleen to become overworked and eventually start to fail.

What is the difference among sickle cell trait, sickle cell anemia and sickle cell disease?

Sickle cell trait is when a person has inherited the gene from one parent and could possibly pass the disease along to offspring.

Sickle cell anemia is when the person has received the sickle cell gene from both parents.

Sickle cell disease is a more general term for sickle cell anemia and other conditions in which a sickle cell gene and another gene that causes abnormalities in red blood cells are inherited together. For example, sickle cell–beta thalassemia is the combination of a sickle cell gene and beta thalassemia, a blood disorder that reduces the production of hemoglobin, the iron-containing, oxygen-carrying part of the red blood cell that also helps it retain its disk shape.

Who is affected by SCD?

Sickle cell disease (SCD) is particularly common among those whose ancestors came from sub-Saharan Africa; Spanish-speaking regions in the Western Hemisphere (South America, the Caribbean, and Central America); Saudi Arabia; India; and Mediterranean countries such as Turkey, Greece, and Italy.

How common is SCD?

SCD affects approximately 100,000 Americans. It is, however, more common among African American and Hispanic Americans:

• SCD occurs among about one out of every 365 Black or African–American births.
• SCD occurs among about one out of every 16,300 Hispanic–American births.
• About one in 13 black or African–American babies is born with sickle cell trait (SCT).

Treating sickle cell disease

Antibiotics and pain relievers can help manage the symptoms of sickle cell anemia and other sickle cell diseases and prevent any infections. Today, two paths also exist to address the underlying cause itself: a stem cell transplant using cord blood or bone marrow from a matched donor, or gene therapy using a patient’s own modified stem cells.  

Gene therapy is a newer option. In December 2023, the FDA approved two gene therapies for sickle cell disease, Casgevy and Lyfgenia, and in July 2026 expanded approval of Casgevy to children as young as 2. These therapies edit or add genes in a patient’s own stem cells rather than replacing them with a donor’s, which removes the need to find a match. But they require treatment at a limited number of specialized centers and aren’t an option for every patient, which is exactly where a sibling’s cord blood keeps its relevance.

In a stem cell transplant, the patient first receives a drug that wipes out their blood-forming bone marrow stem cells. Healthy stem cells from a donor’s cord blood are then transfused into the patient to replace them, and those new cells go on to produce normal, healthy red blood cells.   

Finding a matching unrelated bone marrow donor can be difficult, and stem cells from an unrelated source carry a higher risk of causing graft-versus-host disease. That’s where a sibling’s cord blood becomes the strongest first option when one is available. 

Why Banking Every Child's Cord Blood Matters

This is worth understanding clearly: a child’s own cord blood isn’t used to treat their own sickle cell disease, because SCD is present in every cell that child’s body makes, including the cells in their own stored cord blood. Treating it takes cells from a matched donor, most often a sibling.

That’s why sibling matching is the paramount use for cord blood banking in sickle cell disease, and why every child born into a family has value to bank, not only the one who might get sick. You can’t know in advance which child may need a transplant, or which brother or sister will turn out to be the match. Banking each child’s cord blood keeps that option open across the whole family, so a new baby can end up being exactly what an older sibling needs.

The Odds of a Match

When both parents carry the sickle cell trait, each pregnancy carries defined odds:

• a 25% (1 in 4) chance the child will have sickle cell disease,

• a 50% (1 in 2) chance the child will have the trait only,

• a 25% chance the child will have neither.

Those same odds are why every subsequent birth is a fresh opportunity. Most siblings born after a child with SCD won’t have the disease themselves, and their cord blood becomes a candidate donor. Separately, for matching compatibility, siblings share a 25% chance of being a complete match and a 50% chance of being a partial match for stem cell transplantation.³⁸

Real Stories Close to Home

Our own transplant matrix, a running, dated record of every transplant and infusion performed using cord blood store with Cryo-Cell, lists two sickle cell anemia cases, both using a siblings’ cord blood: 

•    June 2022 – a child treated at Children’s Hospital of Los Angeles, using a sibling’s cord blood unit that had been stored for 83 months. 
•    August 2008 – a 2-year-old treated at North Shore Long Island Jewish Children’s Hospital, using a sibling’s cord blood unit store for 31 months. 

These are historical transplant records, not outcome or efficacy data — the matrix documents that a transplant took place, not whether it was successful. Treatment outcomes vary by patient and can only be assessed by a treating physician.

What Research Shows

A 2017 international registry study— a joint analysis by Eurocord, the European Society for Blood and Marrow Transplantation, and the Center for International Blood and Marrow Transplant Research — followed 1,000 children who received an HLA-identical sibling stem cell transplant for SCD between 1986 and 2013. Most used bone marrow (84%), with peripheral blood (7%) and cord blood (9%) making up the rest. At 5 years, overall survival across the group was 92.9%, with event-free survival at 91.4% (Gluckman et al., 2017).
Furthermore, a study led by Dr. Matthew Hsieh at National Institute of Health (NIH) showed that treatment possibilities for adults with sickle cell anemia have also improved. The study also disproved the long-held hypothesis that adult patients were too vulnerable to organ toxicity and transplant rejection, overcoming this barrier using an innovative, low-toxicity conditioning protocol successfully.

Conclusion

Sickle cell disease presents serious challenges, but advances in stem cell therapy continue to change the landscape of treatment options. By preserving umbilical cord blood at birth, families secure a healthy source of stem cells that offers a viable path for siblings facing this inherited disease. A matched sibling's banked cord blood offers a well-documented, readily available source of donor stem cells for transplant — and because it comes from a related donor, it carries a lower risk of graft-versus-host disease than sources from unrelated donors. This makes cord blood banking a powerful resource for African Americans and Hispanic Americans, who have a higher chance of inheriting sickle cell disease and often face greater difficulty finding matched unrelated donors on public registries.

First published in July 2014. Revised and re-published in September 2016, August 2017, and August 2026.