For the first time, gene editing technology has saved a human life. Doctors in the United Kingdom were able to mass-produce, gene-edited cells to attack the leukaemia into her body and for now, it looks like that the cells fought off her leukaemia.
Because Layla's case had been declared incurable and doctors had exhausted all other options, her parents were granted permission to use the experimental treatment on compassionate grounds. While this is only one case study, what's really exciting is that it's the first evidence that using edited versions of generic, non-personalised cells could work as an effective therapy, paving the way for more affordable and accessible treatment options for a range of cancers.
Layla was born in the UK, and was diagnosed with what's known as acute lymphoblastic leukaemia – an aggressive cancer of the bone marrow – at just three months old. She underwent several rounds of intense chemotherapy, a bone marrow transplant, and took part in an experimental trial all before her first birthday, but the cancer came back.
works by taking immune T-cells from a patient's blood and then genetically engineering them to attack cancerous cells before placing them back in the body. This has been tested so far and results suggest that it can be effective, but it's expensive and time consuming.
Instead the researchers at University College London created an 'off-the-shelf' approach, a healthy person donates a whole bunch of T-cells, which are then modified to make sure they're safe to transfer, creating what the researchers call UCART19 cells. To create these cells they used a pair of 'molecular' scissors, known as TALEN proteins, to switch off certain receptors, ensuring that the UCART19 T-cells only attack leukaemia cells, and not healthy ones. They also removed genes to make the cells invisible, so that they wouldn't be destroyed by other leukaemia drugs.
Layla was given 1 ml of the cells, and two months later, once the doctors confirmed that the leukaemia cells had all been removed, she was given another bone marrow transplant. And the best part is that once the final bone marrow transplant was done, Layla's own immune system kicked back in and destroyed the geneedited, UCART19 cells, so there was no trace left of the gene-editing.
The researchers have now scheduled a proper clinical trial of the UCART19 cells, funded by biotech company Cellectis, to start in early 2016. In addition to making sure the treatment works, these trials will ensure that the modifications made to the T-cells can't be passed on, and aren't toxic to a wider group of patients.