New understanding of the treatment of sickle cell disease

An international team of researchers found a new biophysical marker which can help to improve the awareness of the treatment of sickle cell disease, taking an important step to treat the inherited blood disease. Each year, about 80,000 to 100,000 Americans suffer from the disease. The results will be published online this week in the early version of Progress of National Academy (PNAS), which also has many other studies on recombinant proteins.

Patients with hemoglobin shape sickle cell disease show abnormal shape of hemoglobin. Hemoglobin is protein used by red cells in vivo to carry oxygen. The shape of normal red blood cells is biconcave disc-shaped and is easy to deform and stretch, which is easy to get through narrow blood vessels of the body. In sickle cell disease, abnormal hemoglobin forms fibers. When under the condition of hypoxia, it will lead red blood cells to become flattened, sickle-shaped or harden. The change in shape and hardness can make red blood cells be stuck in the blood vessels, preventing oxygen to be transported to the surrounding tissues. This can cause anemia and extreme pain, affecting the health of body tissues and organs.

Currently, hydroxyurea is the only drug approved by FDA for the treatment of sickle cell disease. The drug improves sickle of red blood cells and is used for the treatment of pain and alleviating the need of blood transfusions for some patients, but it is not effective in all patients. Researchers have long debated what the mechanism of the drug is. So they have conducted a lot of research using recombinant rat proteins.

In the current study, the international team evaluated the biophysical properties of red blood cells - the shape, surface area and volume, biomechanical properties - flexibility and viscosity under normal oxygen conditions and used electromagnetic waves to measure small differences in the physical properties. This technology is known as the common path interferometric microscope, which allows researchers to obtain three-dimensional images of the cells.

The researchers took blood samples from patients with sickle cell disease and divided them into four groups based on the density of red blood cells. The density of normal, disk-shaped red blood cells is minimum, while density of severe sickle cells is maximum. Then they collected blood samples of patients who received hydroxyurea treatment and not. Red blood cells of patients who received treatment showed improvement in physical and biological properties. In addition, physical properties-related red blood cells of patients receiving treatment is greatly related to erythrocytes compared with the level of fetal hemoglobin.

The researchers hope that these biophysical markers can be combined with biochemical and molecular markers to assess the severity of the suffering degree of patients to determine whether hydroxyurea therapy is effective and to monitor the effects of the treatment. Flarebio provides recombinant proteins such as recombinant ITGB2 at good prices.