Friday, July 1, 2011
Cellular GPS Aids in Fight Against Cancer
Imaging Technology Developed at the Mellon College of Science Authorized for Use in Cancer Clinical Trial
New MRI innovation visualizes cellular events in the body. Credit: Frank Harris
Magnetic resonance imaging (MRI) isn’t just for capturing detailed images of torn knee ligaments or the brain. A novel technology developed by Carnegie Mellon University scientist Eric Ahrens will soon allow doctors to use MRI to monitor, in patients, the delivery of a dendritic cell vaccine for treating colorectal cancer. The U.S. Food and Drug Administration has authorized the technology’s use in a Phase I clinical trial at the University of Pittsburgh Cancer Institute (UPCI).
The dendritic cell vaccine is one of many types of cellular therapies that use modified cells—often a patient’s own cells—to fight disease. One of the greatest bottlenecks to such therapies is that there has been no way to monitor where in the body these specialized cells travel.
Ahrens’s cellular MRI technology surmounts this obstacle by allowing researchers to safely monitor where such cells travel throughout the living body using MRI.
“Our technology gives us a surrogate biomarker that provides visual evidence that the cells have gotten to where they need to be,” said Ahrens, associate professor of biological sciences. “In this case, we want the therapeutic cells to migrate to the lymph nodes and activate an immune response.”
The clinical trial at UPCI will use Ahrens’s cellular MRI tool, known by the trade name Cell Sense, to monitor the migration of a dendritic cell vaccine in patients with colorectal cancer. This type of ‘immunotherapy’ holds great promise to provide less toxic, patient-specific cancer treatments. In the laboratory, a patient’s dendritic cells, a type of immune cell, will be modified in such a way that it stimulates native immune cells in the body to target tumor antigens and fight residual cancer cells for extended periods of time. The dendritic cells will also be labeled with Cell Sense. The modified cells will then be reintroduced into the patient, where they can be tracked using MRI.
Cell Sense is a colloidal suspension, or ‘nanoemulsion’, of tiny fluorocarbon droplets. The nuclei of the fluorine atoms in the nanoemulsion send a signal that allows the cell to be detected by MRI. Since fluorine is not found in abundance in the human body, the labeled cells stand out in an MRI image, making it possible to see where the vaccine has traveled.
“It’s tremendously satisfying to have taken the concept of this fluorocarbon molecule all the way to its imminent use in human patients,” said Ahrens. “The FDA’s Investigational New Drug authorization hopefully will be a huge step toward using Cell Sense to investigate other types of treatments.”
Outside of cancer, cellular therapies are being explored to treat a wide range of conditions including heart disease, Parkinson’s disease, spinal cord injury and diabetes.
The Cell Sense solution, initially developed by Ahrens and collaborators at Carnegie Mellon, is licensed to and manufactured by Celsense, Inc. Ahrens serves as a consultant to Celsense. The clinical investigators include Drs. Pawel Kalinski and David Bartlett at UPCI, and Amy Wesa at Celsense. The clinical trial has been funded by the National Cancer Institute at the National Institutes of Health.
By: Amy Pavlak