Scientists have long used imaging technologies to peer into our bodies and to diagnose what ails us. Robarts Research Institute scientist Paula Foster, however, has taken this a step further and is looking directly at individual cells.
“We were the first in the world to show you can detect a single iron-labelled cell in a living animal with MRI,” she says.
The discovery helps scientists track cellular movement and shed light on diseases like cancer and Multiple Sclerosis. “Cells are early detectors, including cancer cells,” Foster says. “There is always a cellular event – pre-disease states – we can detect through imaging.”
Having spent the early years of her career developing the tools necessary for cellular tracking, Foster and her group have narrowed the best applications for the technology and are focusing on two main areas: cancer and stem cells.
Though her team is working on the nanoscale – a mere billionth of a metre in size – the iron they inject into cells creates ‘black holes’ in the magnetic resonance image, allowing them to track cellular movement. This technology is far less invasive than previous methods of research and analysis, which required autopsies or biopsies.
Much of Foster’s work deals with metastatic breast cancer to the brain and looks at both the ability to detect and track cancerous cells, and methods for using immune cells as therapy.
“Breast cancer treatments are getting better, but it’s not the breast cancer that kills, it’s the metastasis, particularly when it gets into the brain,” she says.
Foster and her group are now separating diverse cancer cells and injecting specific populations into animal models to better understand why they act differently, including why some dormant cells might metastasize, then do nothing before proliferating.
Immunotherapy, where immune cells recovered from blood or bone marrow are injected into cancer cells and ‘educated’ to find the disease, may provide promising new treatments and opportunities for Foster to track their success.
“The most exciting thing for me is cancer immunotherapy is already happening in cancer centres,” she says. “They are using cells for therapy and this gives us our first opportunity to image their success – right now, the only outcome is ‘is the patient getting better?'”
Foster also uses imaging technologies to study stem cells, particularly in how they relate to Multiple Sclerosis, spinal cord injury and vascular injury.
“There are very encouraging reports in pre-clinical trials showing positive outcomes,” she says. “The fundamental question to address is how can you maximize stem cell delivery to get cells to go where you want them to.”
In the long run, Foster is interested in using MRI for whole-body screening, and to use the technology to track metastasis of cancer cells through the body.
“As you can imagine, there is an innumerable number of questions to be asked that will keep me busy for a long time,” she says.
For more, please visit: www.imaging.robarts.ca/~pfoster