the ability of immune cells to attack
cancer.
could spark a biomedical duel
between China and the United
States.
A Chinese group has become the first to
inject a person with cells that contain genes edited using the
revolutionary
CRISPR-Cas9 technique.
Earlier clinical trials using cells edited with a different technique have excited clinicians.
The introduction of CRISPR, which is simpler and more efficient than other techniques, will probably accelerate the race to get gene-edited cells into the clinic across the world, says Carl June, who specializes in immunotherapy at the University of Pennsylvania in Philadelphia and led one of the earlier studies.
June is the scientific adviser for a planned US trial that will use CRISPR to target three genes in participants' cells, with the goal of treating various cancers.
He expects the trial to start in early 2017. And in March 2017, a group at Peking University in Beijing hopes to start three clinical trials using CRISPR against bladder, prostate and renal-cell cancers.
Those trials do not yet have approval or funding.
Protein target
Lu's trial received ethical approval from a hospital review board in July.
Injections into participants were supposed to begin in August but the date was pushed back, Lu says, because culturing and amplifying the cells took longer than expected and then the team ran into China's October holidays.
The researchers removed immune cells from the recipient's blood and then disabled a gene in them using CRISPR-Cas9, which combines a DNA-cutting enzyme with a molecular guide that can be programmed to tell the enzyme precisely where to cut.
The disabled gene codes for the protein PD-1, which normally puts the brakes on a cell's immune response:
Lu's team then cultured the edited cells, increasing their number, and injected them back into the patient, who has metastatic non-small-cell lung cancer.
The hope is that, without PD-1, the edited cells will attack and defeat the cancer.
Safety first
Lu says that the treatment went smoothly, and that the participant will get a second injection, but declined to give details because of patient confidentiality.
The team plans to treat a total of ten people, who will each receive either two, three or four injections. It is primarily a safety trial, and participants will be monitored for six months to determine whether the injections are causing serious adverse effects.
Lu's team will also watch them beyond that time to see if they seem to be benefiting from the treatment.
Other oncologists are excited about CRISPR's entry onto the cancer scene.
Antonio Russo of Palermo University in Italy notes that antibodies that neutralize PD-1 have successfully put lung cancer in check, boding well for a CRISPR-enabled attack on the protein.
But Naiyer Rizvi questions whether this particular trial will succeed.
The process of extracting, genetically modifying and multiplying cells is,
He doubts it will be superior to the use of antibodies, which can be expanded to unlimited quantities in the clinic.
Lu says that this question is being evaluated in the trial, but that it's too early to say which approach is better.
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