The spleen’s job is to filter our blood. When people are critically ill or have received traumatic injuries, however, the spleen alone is sometimes not able to remove enough of the pathogens on its own – potentially-fatal sepsis is the result. In order to help avert such an outcome in those situations, scientists from the Wyss Institute for Biologically Inspired Engineering at Harvard University are developing a device known as the spleen-on-a-chip.

The patient’s blood is circulated through the device. The process begins with magnetic nanobeads being mixed with the blood. Those beads are coated with a genetically engineered version of a human blood opsonin protein, that bonds with pathogens such as bacteria, viruses, parasites, fungi and toxins.

The blood/nanobead mixture proceeds to flow through a series of microchannels, in which magnets are used to pull the beads back out. The beads bring the pathogens with them, leaving all the regular components of the now-cleansed blood (such as the cells and proteins) to be returned to the patient.

Anticoagulants aren’t required to keep the blood from clotting within the microchannels, as their inside surfaces are coated with a super-hydrophobic Harvard-developed material known as SLIPS.

The Wyss Institute (which also brought us the gut-on-a-chip) recently received a US$9.25 million contract from DARPA, to further develop the spleen-on-a-chip. DARPA has reason to be interested in the technology, as it could be used to treat soldiers injured on the battlefield.

Testing on large animals is now being planned, with human trials down the road.

Source: Harvard University