The treatment of many blood-borne illnesses has reached a breakthrough
with the recent announcement of a device able to cleanse the blood of disease
pathogens. With this in mind, bioengineer Donald Ingber and his team set
out to develop an artificial spleen that is able to filter blood through the
use of proteins and magnets. More specifically, the device uses modified
mannose-binding lectin (MBL), a human protein that binds to sugar molecules on
the surface of over 90 bacteria, viruses, and fungi, as well as the toxins
released by dead bacteria that cause sepsis in the first place.
By adding MBL to magnetic nano-beads and passing blood
through the device, the pathogens in the blood bind to the beads. A magnet then
pulls the beads and their constituent bacteria from the blood, which is now
clean and able to be put back into the patient. Ingber and his team tested the
device on infected rats, and after finding that 89% of infected rats were still
alive by treatment’s end, wondered whether the device could handle the blood
load of an average human adult (about five litres). By passing
similarly-infected human blood through the device at 1L/hour, they found the
device removed the vast majority of pathogens within five hours.
Once the
bulk of the bacteria is removed from the patient’s blood, their immune system
can handle their weakened remains. Ingber is hopeful that the device will be
able to treat larger-scale diseases, such as HIV and Ebola, where the key to
survival and effective treatment is to lower the pathogenic level of the
patient’s blood before attacking the disease with powerful medicine.
