Feb 22, 2019
One enduring challenge in human organ transplantation is detecting rejection crises early enough to save the transplanted organ with the administration of anti-rejection drugs such as high dose steroids. Typically, rejection is diagnosed with biopsies. By the time a biopsy shows conclusive changes, much of the organ is often destroyed. A new technique being developed at the Georgia Institute of Technology may change all that.
The diagnostic tool employs nanotechnology to build an ingenious probe that acts as an early warning beacon for organ rejection. It is a nanoball with iron oxide in the middle, a sugar coating of dextran, and some polyethylene glycol or antifreeze to prevent the body from quickly degrading it. The ball is covered with amino acid florescent spikes. These nanoballs are injected into the transplanted organs and remain there.
As the transplant patient’s T cells bulk up to mount a rejection of a heart, liver, or kidney, they begin to produce the toxic enzyme granzyme B. Even in tiny amounts, this enzyme will begin to release the small fluorescent molecules from the nanoball. When they pass out in urine, they make it glow under black light.
This probe system can serve not only as an early warning signal for rejection but as a sensitive monitor for the effectiveness of anti-rejection therapy. So far, the nanoballs work well in mice. Next, the system will be perfected in men.
#transplantation #rejection #nanotechnology #fluorescence #healthnews #healthtips
Quoc D. Mac, Dave V. Mathews, Justin A. Kahla, Claire M. Stoffers, Olivia M. Delmas, Brandon Alexander Holt, Andrew B. Adams, Gabriel A. Kwong. Non-invasive early detection of acute transplant rejection via nanosensors of granzyme B activity. Nature Biomedical Engineering, 2019; DOI: 10.1038/s41551-019-0358-7