Real Voices interview: Bobby Gaspar
Meet Bobby, a paediatrician at Great Ormond Street Hospital
What do you do?
I came to Great Ormond Street about 20 years ago as a children’s doctor, intending to stay for about six months. I’m still here.
What do you work on?
I work on primary immunodeficiencies. These conditions result from a single genetic defect, which means that children are born without an immune system, so they can’t fight infection effectively. Over 200 genetic defects have been identified. They range from people who get relatively minor but recurrent infections on a regular basis to those who have no immunity at all and are susceptible to all kinds of infection from a very early age.
Severe combined immune deficiencies – SCID – is a blanket term for very severe immune deficiencies. Probably 15 to 20 children are born with SCID per year in the UK.
What causes SCID?
The immune system is pretty complex. It’s got lots of different white cells that have different functions. A major group of immune cells are the lymphocytes. Children with SCID have very low numbers of lymphocytes because a genetic defect stops these white blood cells being made.
The term ‘bubble babies’ is often used, because in the past children had to be kept in plastic bubbles as they were vulnerable to everything. Nowadays, they are kept isolated in very clean cubicles and there are strict restrictions on who they can see and where they can go.
Is there a cure?
Up until 20 years ago, the only way we could rebuild the immune system was to give children a bone marrow transplant, from a healthy individual. But that only works if there is a good matched donor available.
We wanted to try and find a better way of correcting these conditions. So we take the child’s own cells, usually from the bone marrow, and in the laboratory put a working copy of the gene into them. We’ve got a delivery vehicle, or vector, which is based on HIV. We disable the virus – taking out the bad bits – but keep the properties that HIV has to get into cells.
Immune deficiencies are the first conditions in which gene therapy has been shown to correct a genetic disease. We’re still working on gene therapy for SCID, but we’re also working on it for other immune deficiencies that are less severe but which still cause significant problems.
Gene therapy is currently only available at a few specialised centres worldwide, including Great Ormond Street Hospital. However, in the future, we want to make gene therapy into an approved genetic medicine so that it is available for babies with SCID wherever they might be.