By: Gina Kolata, New York Times
For the first time, scientists have found a way to efficiently and precisely remove genes from white blood cells of the immune system and to insert beneficial replacements, all in far less time than it normally takes to edit genes.
If the technique can be replicated in other labs, experts said, it may open up profound new possibilities for treating an array of diseases, including cancer, infections like HIV and autoimmune conditions like lupus and rheumatoid arthritis.
The work, published in the journal Nature, “is a major advance,” said Dr. John Wherry, director of the Institute of Immunology at the University of Pennsylvania, who was not involved in the study.
But because the technique is so new, no patients have yet been treated with white blood cells engineered with it.
“The proof will be when this technology is used to develop a new therapeutic product,” said Dr. Marcela Maus, director of cellular immunotherapy at Massachusetts General Hospital.
That test may not be far away. The researchers have already used the method in the laboratory to alter the abnormal immune cells of children with a rare genetic condition. They plan to return the altered cells to the children in an effort to cure them.
Currently, scientists attempting to edit the genome often must rely on modified viruses to slice open DNA in a cell and to deliver new genes into the cell. The method is time-consuming and difficult, limiting its use.
Despite the drawbacks, the virus method has had some success. Patients with a few rare blood cancers can be treated with engineered white blood cells — the immune system’s T-cells — that go directly to the tumors and kill them.
This type of treatment with engineered white cells, called immunotherapy, has been limited because of the difficulty of making viruses to carry the genetic material and the time needed to create them.
But researchers now say they have a found a way to use electrical fields, not viruses, to deliver both gene-editing tools and new genetic material into the cell. By speeding the process, in theory a treatment could be available to patients with almost any type of cancer.
“What takes months or even a year may now take a couple weeks using this new technology,” said Fred Ramsdell, vice president of research at the Parker Institute for Cancer Immunotherapy in San Francisco. “If you are a cancer patient, weeks versus months could make a huge difference.”
“I think it’s going to be a huge breakthrough,” he said.
The Parker Institute already is working with the authors of the new paper, led by Dr. Alexander Marson, scientific director of biomedicine at the Innovative Genomics Institute — a partnership between University of California, San Francisco and the University of California, Berkeley — to make engineered cells to treat a variety of cancers.
In the new study, Marson and his colleagues engineered T-cells to recognize human melanoma cells. In mice carrying the human cancer cells, the modified T-cells went right to the cancer, attacking it.
The idea of engineering T-cells without using a virus is not new, but the immune cells are fragile and hard to keep alive in the lab, and it has always been difficult to get genes into them.
Already the scientists are talking to the Food and Drug Administration about using the new method to precisely attack solid tumors, as well as blood cancers.
“Our intent is to try to apply this as quickly as possible,” Ramsdell said.
Barbara Jacoby is an award winning blogger that has contributed her writings to multiple online publications that have touched readers worldwide.