Latest use of technology seems to avoid use of embryonic cells, may spur international race
Experiments in China with a controversial gene modifying process may hold the key to a cure for cancer, according to the science journal Nature.
A team at Sichuan University in Chengdu has become the first in the world to inject a person with cells that contain genes edited using the CRISPR–Cas9 technique.
Developed in 2014, CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) allows scientists to cut out a bad piece of DNA and replace it with the correct sequence.
In late October, Chinese oncologist Lu You injected modified cells into a patient as part of a clinical trial at the West China Hospital in Chengdu, Nature reported.
Lu’s experiments seem to avoid ethical problems such as using the cells of embryos. According to the article, researchers removed immune cells from the recipient’s own blood and then disabled a gene in them using CRISPR–Cas9. His team then cultured the edited cells, increasing their number, and injected them back into the patient. The hope is that the edited cells will attack and defeat the cancer.
Father Tad Pacholczyk, director of education at the National Catholic Bioethics Center (NCBC), said the new development offers an “exciting glimpse” into some of the likely future applications of CRISPR-Cas9.
“Hopefully there won’t be any unanticipated side-effects from the study, but even if there are, I think researchers will probably work out the kinks pretty quickly,” Father Pacholczyk said. “This technique represents a remarkable snippet of biotechnological wizardry and will likely be used in the future to therapeutically address a broad range of diseases. Ethically speaking, this particular news story doesn’t raise concerns beyond the usual range of questions about anticipated risks v. benefits for the patient being treated, being sure that sufficient animal model work has preceded the human trials, the high costs that are likely to be involved, etc.”
The ethicist expressed hope that in the future scientists will not “turn down the dark alley of using this technique to edit genes in human embryos, nor otherwise go in the direction of introducing germ-line genetic changes.”
In the past, Father Pacholczyk warned that the ability to rewrite the human genome at will through precise DNA editing techniques raises “substantial concerns” about misusing the technology.
“In fact, researchers are already discussing the possibility of going beyond therapies and treatments, and instead, using CRISPR and other gene-alteration technologies to enhance human characteristics,” the organization said, offering as an example the possibility of enhancing the performance of athletes and soldiers by engineering changes in the genes of human muscles.
But the step taken in Chengdu seems to be creating some international competition a la an earlier scientific rivalry: the “space race” between the United States and the former USSR.
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. “I think this is going to trigger ‘Sputnik 2.0’, a biomedical duel on progress between China and the United States, which is important since competition usually improves the end product,” he says.
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, Nature says.