SAN DIEGO – Scientists at La Jolla's Salk Institute for Biological Studies say they've taken a significant step toward using stem cells and gene therapy to cure a genetic disease.
The team led by Salk Professor Juan-Carlos Izpisua Belmonte corrected a defective gene in cells taken from patients with Fanconi anemia, a disease that can lead to bone marrow failure, leukemia and other cancers.
Their work, published online Sunday by the journal Nature, offers the first proof that the technology can work in human cells – though more work remains for it to be tried in patients.
“We haven't cured a human being, but we have cured a cell,” Belmonte said. “In theory we could transplant it into a human and cure the disease.”
The researchers received a $6.6 million grant from California's stem cell institute in April to continue the work. One big remaining problem is to prevent the reprogrammed cells from inducing tumors.
Belmonte said the work has taken a little more than two years already. Many of the techniques the team used are relatively new, he said, so it took time to learn how to make them work efficiently.
The approach involved taking hair or skin cells from patients with Fanconi anemia, then using a series of steps to correct the gene defect and reprogram the cells into induced pluripotent stem cells – cells created synthetically from skin or other cells.
They used gene therapy techniques developed in the lab of Salk Professor Inder Verma, and also collaborated with researchers at the Center of Regenerative Medicine in Barcelona, Spain, and CIEMAT in Madrid, Spain.
“If we can demonstrate that a combined (stem cell)-gene therapy approach works in humans, then there is no limit to what we can do,” Verma said.
The scientists said the cells that resulted from their work were indistinguishable from human embryonic stem cells or induced pluripotent stem cells from healthy donors.
The remaining work will include improving the technology to produce transplantable cells. Belmonte said many labs are working on ways to address the cancer risk the cells pose.
“It's been 10 years since human stem cells were first cultured in a Petri dish,” Belmonte said. “The hope in the field has always been that we'll be able to correct a disease genetically and then make (stem cells) that differentiate into the type of tissue where the disease is manifested and bring it to clinic.”