Using smart bombs to kill old cells

A new nanotechnology developed at the University of Leicester could lead to people living longer.

A new tool that detects and destroys old cells that interfere with the normal functions of body tissues has been developed at the University of Leicester, with the goal of improving the symptoms of ageing in humans.

Previous research has shown that when animals age, they progressively accumulate old cells in their organs. As their numbers increase, such cells interfere with normal tissue functions and they can even turn their neighbour cells old as well. For these reasons, they have sometimes been called ‘zombie’ cells. 

It has been shown that by eliminating these cells, it’s possible to delay the symptoms associated with ageing and prolong the lifespan of animals. But until now, it has never been possible to detect these cells inside the human body and selectively kill them. Cell biologists and chemists at the University of Leicester have collaborated to develop a new tool to do precisely that, with the goal of defining new strategies to improve ageing.

Research lead, Dr Salvador Macip, Associate Professor, Department of Molecular and Cell Biology, said: “This is a scientific breakthrough that could improve ageing in humans. More research needs to be carried out, but based on what we know so far, by killing ‘zombie’ cells it should be possible to ameliorate ageing and change the way diseases like diabetes, Alzheimer’s or obesity are treated in the future.”

The Mechanisms of Cancer and Ageing lab at the University of Leicester, directed by Dr Macip, was able to overcome the initial obstacle of finding old cells in tissues when they discovered a series of proteins overexpressed on the surface of these cells. Now, these markers have been used to design “smart bombs” that can hunt old cells and release a fatal drug inside them.

These advancements, published online in Nanoscale Horizons, have been possible thanks to a nanotechnology – Molecularly Imprinted Nanopolymers (nanoMIPs) – developed by Professor Sergey Piletsky’s team in the University of Leicester’s Department of Chemistry and MIP Diagnostics Limited. MIPs are very small entities that can be moulded to recognise any protein of a cell. They were made to recognise one of the proteins abundant on the surface of old cells and then tagged with a fluorescent molecule to aid in their detection.

These nanoparticles, produced using an innovative solid-phase approach owned by MIP Diagnostics, were able to detect old cells in the laboratory and, when injected into mice of different ages, they highlighted the tissues of older animals. Importantly, when the nanoparticles were loaded with a drug, they were able to specifically target and kill the old cells in the lab.

This is the first targeted nanoparticle designed against old cells and has the potential to be used as a diagnostic and therapeutic tool in humans. Furthermore, thanks to the generic nature of the proprietary imprinting process used in this research, MIP Diagnostics can offer the possibility to design custom-made nanoMIPs against other clinically relevant targets.

• ‘Detecting and targeting senescent cells using molecularly imprinted nanoparticles’ is available to read online now, Nanoscale Horizons, 2019, DOI: 10.1039/C8NH00473K