Gene 'scissors' hope for sickle cell disease
Researchers at Barts Health NHS Trust have recruited the first patient in the UK to a cutting-edge clinical trial which looks at using genetic 'scissors' to repair faulty DNA in those with sickle cell disease.
Sickle cell disease is the name for a group of inherited health conditions that affect the red blood cells. The most serious type is called sickle cell anaemia.
The disease is particularly common in people with an African or Caribbean family background.
People with the condition produce unusually shaped red blood cells that can cause problems because they do not live as long as healthy blood cells and can block blood vessels. As a result, sickle cell patients can be more prone to infection and suffer from painful episodes known as crises, which can leave them needing hospital treatment such as blood transfusions.
The trial uses cutting-edge technology known as CRISPR/Cas9 to edit genes. Gene-editing can be used to add, remove, or alter DNA in the genome to potentially correct the harmful impact of genetic diseases, like sickle cell disease.
In sickle cell patients, the protein called haemoglobin, found in red blood cells and responsible for carrying oxygen to the body, is abnormal. This abnormality means it can form stiff rods, or sickles, in the blood cell. These sickle-shaped red blood cells are inflexible and can create blockages that slow or stop the oxygen from being delivered to the body. This can cause health issues, such as pain and damage that can occur in any organ.
In the trial, stem cells are collected from bone marrow and then the DNA within the cells is edited using CRISPR-Cas9 gene-editing technology. This is done outside the body in a lab before the edited stem cells are infused back into the patient.
The goal of the editing is to reduce expression of a gene called BCL11A in the blood stem cells and allow the body to begin reproducing foetal haemoglobin (HbF), which is normally not produced in adults. The elevation of HbF has the potential to eliminate painful and debilitating sickle crises for people with sickle cell disease.
Louise Taylor, ITP and Immune Haematology Nurse Consultant and Clinical Haematology Trials Manager at Barts Health, said: “We are very happy to be able to offer this leading technology to our patients.
“Sickle cell is a hugely debilitating condition that patients live with for life, and the only treatments we have now are ones which alleviate symptoms – they do not cure the disease itself.
“This trial is using state-of-the-art medicine to hopefully bring about better outcomes for sickle cell patients.”
