Sepsis is a whole-body inflammatory nightmare caused by an infection of the blood, and it’s not only deadly, but difficult to treat, according to Don Ingber, director of Wyss Institute for Biologically Inspired Engineering, at Harvard.
Not knowing the specific pathogens causing the condition, doctors will often use broad spectrum antibiotics that have only limited chance of success. And treating the condition is a race against time. Ingber says for every hour patients are on the wrong drug, their mortality rate increases by nearly 10%. Sepsis eventually shuts down the body’s vital organs.
Blood infections have been a particular problem for the military in Afghanistan and Iraq. Which is one reason DARPA, the famed research group, is keen to find a better treatment. It recently awarded $9.25 million to the Wyss Institute, because it believes it might have one.
Its so-called "Spleen-on-a-Chip" is a blood cleaning device a little like a kidney dialysis machine. Blood goes out through one vein, and back through another. The key is what’s introduced by syringe beforehand: magnetic nano-beads coated in a protein that binds to bacteria, fungi, parasites, and some toxins. When the blood flows through micro-channels in the device, it pulls the pathogens free with a magnet, leaving the fluid clean.
"The idea with this therapy is that you could use it right away without knowing the type of infection," says Ingber. "You can remove pathogens and infections without triggering that whole cascade that gets worse and worse."
The technique also takes out dead pathogens (killed by antibiotics) that can also cause inflammations, if there are enough of them. And it can be used in combination with antibiotics at the same time.
Wyss is currently testing the "biospleen"—the channels mimic the structure of a real spleen—on rats. The DARPA money will now allow it to trial it with bigger animals, like pigs. Ingber says a fully serviceable device could be ready within five years.
It’s one of more than a dozen organs-on-chips that Wyss is developing, including a lung-on-a-chip and a gut-on-a-chip. The larger aim, says Ingber, is to raise the effectiveness of drug testing, and improve understanding of how the body reacts to disease.