Dictyostelium cells navigating a version of the maze at Hampton Court Palace in London
Luke Tweedy (CRUK Beatson Institute), Michele Zanoni (University of Strathclyde) and Robert Insall (University of Glasgow)
Cells can rapidly solve artificial mazes by generating chemical gradients to predict the fastest route, a clever trick that may explain how they migrate through the body.
Our cells often have to traverse highly complicated routes. “If you cut your finger, for example, your white blood cells have to find their way around all sorts of things like nerves, bones and skin cells to get from your blood vessels to the wound,” says Robert Insall at the Cancer Research UK Beatson Institute in Glasgow.
It is well known that cells can steer short distances by sensing and moving towards attractive chemicals, or “chemoattractants”, in their direct vicinity, but how they navigate longer routes has been unclear.
To find out, Insall and his colleagues studied the paths taken by cells through computer-generated and real-life mazes.
They found that cells determine the best route ahead by using enzymes to break down chemoattractants in their immediate surroundings, then sensing the extent to which the chemicals are replenished from different directions. “They read the resulting chemical gradients to see where to go,” says Insall.
This allows cells to tell the difference between dead ends and clear paths, because fresh chemoattractant only returns along clear paths, he says. “As cells approach a junction leading to a dead end and a non-dead end, they slurp up all the chemoattractant from both sides, but only the good side gets replenished.”
This strategy allowed mouse pancreatic cancer cells and soil-based amoeba cells called Dictyostelium discoideum to rapidly solve artificial mazes made out of silicon, including a miniature replica of the famous hedge maze at Hampton Court Palace in London.
“Cells are better at solving these mazes than people because they can sniff out a path before even going in, whereas we can’t tell there’s a blind corner until we’ve actually gone in and seen it with our eyes,” says Insall.
The researchers hope that the findings will improve our understanding of complex cell-migration processes inside the body, including how cancer cells spread and how individual cells that make up embryos find their correct positions.
Journal reference: Science, DOI: 10.1126/science.aay9792
More on these topics: