Researchers at EPFL have demonstrated a new method to make immunotherapy a more effective and directed treatment against cancer. The team designed microparticles containing drugs that are only released when T cells physically squeeze them, on contact with cancer cells.
Our own immune system is one of the most powerful tools we have in the fight against cancer, but it often needs a nudge. Immunotherapy offers just that, either through drugs that recruit extra immune cells to a tumor site or by removing immune cells, supercharging them against cancer then returning them to the body to get to work.
Results have proven astonishing – when it works. Unfortunately, the therapy fails more often than not, and using a stronger form of treatment can trigger a potentially deadly immune system overreaction.
So for the new study, the team conducted a proof of concept for a method that boosts the killing power of the body’s T cells only in the presence of cancer. While most immunotherapy techniques use biochemical signals to trigger the release of drugs, the new system relies on a novel trigger – a physical squeeze.
“When T cells come into contact with cancer cells, they destroy the cells by releasing chemical compounds as well as applying mechanical force,” says Li Tang, lead author of the study. “The T cells’ mechanical force is only triggered when they are touching their target cells.”
The researchers started with porous silica microparticles. Those pores are filled with anticancer drugs, and capped off with plugs made of double-stranded DNA. The idea is that when the T cells come in contact with cancer cells, they give the tumors and the microparticles a little squeeze, which breaks the DNA caps and releases the drugs.
The technique was tested in human cells in culture and in live mice, and in both cases it significantly enhanced the cancer-killing effects of the T cells.
Ultimately, the plan is to shrink the particles down to the nano scale, and adapt the system so that it can be attached to T cells, carried to the target location and release the drugs to help the immune system in the fight.
“For now we’ve only just completed the proof of concept stage,” says Tang. “We’ve shown that our idea works, but we need to develop the technology further before we can start conducting clinical trials.”
The research was published in the journal Material Horizons.
Source: EPFL