Discovering Sickle Cell Therapies

Proteins TR2 and TR4 could help treat sickle cell disease

(RxWiki News) For sickle cell disease patients, even everyday events can be difficult because of debilitating pain episodes and chronic organ damage.  A trigger for producing normal red blood cells could lead to a treatment.

Increasing expression of proteins TR2 and TR4 could help increase hemoglobin and reduce organ damage. Sickle cell disease is caused by abnormal hemoglobin, a protein inside red blood cells, that causes them to become crescent shaped.

"Talk to a hematologist about available treatments."

Dr. Andrew Campbell, lead author of the study, and a pediatrician and director of the Pediatric Comprehensive Sickle Cell Program at the University of Michigan Cancer Center, said that the majority of sickle cell disease patients are diagnosed early in childhood when adult hemoglobin usually replaces fetal hemoglobin.

However, depending on the severity of the disease there may be a stronger level of fetal hemoglobin in red blood cells.

During the study in mice, researchers increased expression of proteins TR2 and TR4. They found that doing so more than doubled the level of fetal hemoglobin produced in sickle cell mice and reduced organ damage.

The average fetal hemoglobin was 7.6 percent in sickle cell mice, while mice treated with the proteins had an average fetal hemoglobin of 18.6 percent. Anemia and red blood cell turnover also improved with the treatments.

Clinical trials are still needed to determine whether the method would be helpful in treating human patients with sickle cell disease.

Dr. Campbell noted that hydroxyurea is U.S. Food and Drug Administration approved to increase fetal hemoglobin in sickle cell patients, and some patients respond well to it. However he expressed concern, particularly for children, because the long-term consequences of taking the drug remain unknown.

The research was recently published in the Proceedings of the National Academy of Sciences.

Review Date: 
November 4, 2011