How Cells Can Find Their Way Through the Human Body

Bob Yirka / Phys.org / August 28, 2020

A team of researchers affiliated with multiple institutions in the U.K. has discovered how cells are able to travel so accurately through the human body. In their paper published in the journal Science, the group describes a theory they developed to explain cell orienteering and how they tested it using mazes.

When the body is injured, such as being poked with a needle, the immune system responds by sending white blood cells to kill any bacteria that might be trying to enter through the wound.

But how do the cells know how to find the wound?

Prior research has shown that cells use chemicals in the body known as chemoattractants to navigate short distances. White blood cells can sense and move toward them—but it only works for short distances. In this new effort, the researchers found that cells can use such chemoattractants in a different way to navigate longer and more complicated pathways.

The researchers theorized that certain cells navigate by breaking down chemoattractants that are close to them. They then sense the degree to which the chemoattractants are replenished, and most importantly, in which direction. By noting the position of the new chemoattractants, they are able to move toward their desired destination. As an example, a white blood cell working its way to a wound upon finding a fork in the road would choose the path with the most or newest chemoattractants after it breaks them down in both directions.