Carnegie Mellon MRI technology that non-invasively locates, quantifies specific cells in the body
"With our technology we can image specific cells in real-time with exquisite selectivity, which allows us to track their location and movement and to count the apparent number of cells present. We then use conventional MRI to obtain a high-resolution image that places the labeled cells in their anatomical context," said Ahrens, an associate professor of biological sciences at the Mellon College of Science.
The ability to track the movement and eventual location of specific immune cells is critical for understanding the cells' role in disease and therapeutic mechanisms, and for developing effective cell-based therapeutics. Other MRI methods for visualizing cells use metal-based contrast agents, which can make it difficult to clearly identify labeled cells in the body, according to Ahrens.
"The large background signal from mobile water and intrinsic tissue contrast differences can often make it challenging to unambiguously identify regions containing these metal-ion labeled cells throughout the body, which is the current state of the art," Ahrens said.
Ahrens's new approach — fluorocarbon labeling — solves this problem by producing images that clearly show the labeled cells at their precise location in the body. Ahrens first labels the cells of interest with a perfluoropolyether (PFPE) nanoemulsion, which is a colloidal suspension of tiny fluorocarbon droplets. Then, he introduces the labeled cells into an animal subject and tracks the cells in vivo using 19F MRI.
While conventional MRI detects the nuclear magnetic resonance signal from protons contained in the mobile water in tissue, 19F MRI detects the signal from the nucleus of the fluorine atom. Fluorine is not normally present in the body at sufficient concentrations to detect, so when Ahrens labels cells with PFPE, he can detect this fluorine 'tracer' with MRI after the cells are transplanted into the body. The Ahrens' team has recently used the PFPE technology to label and track dendritic cells and T cells in a mouse model of type I diabetes, a disease in which immune cells infiltrate the pancreas, attacking and damaging the body's own cells.
Most read news
Other news from the department science
Get the analytics and lab tech industry in your inbox
From now on, don't miss a thing: Our newsletter for analytics and lab technology brings you up to date every Tuesday. The latest industry news, product highlights and innovations - compact and easy to understand in your inbox. Researched by us so you don't have to.