About the study
Sickle cell disease (SCD) is an inherited blood disorder. It results from a single genetic
change (mutation) in red blood cells (RBCs). RBCs are the cells that carry oxygen to the
body. In people with SCD, some RBCs are abnormal and die early. This leaves a shortage of
healthy RBCs. Researchers want to learn more about how long RBCs live in the human body.
To study how long RBCs live in people with and without SCD.
People age 18 and older who either have SCD, had SCD but were cured with a bone marrow
transplant, have the sickle cell trait (SCT), or are a healthy volunteer without SCD or SCT
Participants will be screened with a medical history and physical exam. They will give a
Participants will have a small amount of blood drawn from a vein. In the laboratory, the
blood will be mixed with a vitamin called biotin. Biotin sticks to the outside of RBCs
without changing their function, shape, or overall lifetime. This process is known as biotin
labeling of RBCs. The biotin labeled RBCs will be returned to the participant via vein
Participants will give frequent blood samples. Their RBCs will be studied to see how many
biotin labeled RBCs remain over time. This shows how long the RBCs live. Participants will
give blood samples until no biotin labeled RBCs can be detected.
During the study visits, participants will report any major changes to their health.
Participation lasts for up to 6 months.
– Age 18 or greater with a confirmed diagnosis of homozygous sickle cell anemia (HbSS),
sickle cell trait (HbAS), or ethnic-matched healthy volunteer (HbA).
– Normal renal function: creatinine <1.5 mg/dL, proteinuria <1+.
- Negative direct antiglobulin test (DAT).
- Ability to give informed consent to participate in the protocol.
– Any active chronic illness other than sickle cell disease.
– Blood transfusion within the preceding 90 days
– Active viral, bacterial, fungal, or parasitic infection.
– Consumption of biotin supplements or raw eggs within 30 days.
– Blood loss within the previous 8 weeks >30mL including but not limited by blood
donation, trauma, gastrointestinal bleeding.
– Pre-existing, naturally occurring antibodies against biotin