Artificial spleen cleans up blood infections

Researchers have developed an artificial 'biospleen' that may be able to quickly clean blood of everything from E coli to Ebola.
The device filters blood to rid the body of infections - even those caused by unknown pathogens.
Blood infections can be very difficult to treat, and can lead to sepsis, an often-fatal immune response.
The device, developed by a team led by Donald Ingber, a bioengineer at the Wyss Institute for Biologically Inspired Engineering in Boston, Massachusetts, used a modified version of the protein mannose-binding lectin (MBL).
MBL protein is found in humans and binds to sugar molecules on the surfaces of more than 90 different bacteria, viruses and fungi, as well as to the toxins released by dead bacteria that trigger the immune overreaction in sepsis.

The researchers coated magnetic nanobeads with MBL. As blood enters the biospleen device it passes by the MBL-equipped nanobeads, which bind to most pathogens.

A magnet on the biospleen device then pulls the beads and their quarry out of the blood, which can then be routed back into the patient, 'nature.Com' reported.
To test the device, Ingber and his team infected rats with either E coli or Staphylococcus aureus and filtered blood from some of the animals through the biospleen.
Five hours after infection, 89 per cent of the rats whose blood had been filtered were still alive, compared with only 14 per cent of those that were infected but not treated.

The researchers found that the device had removed more than 90 per cent of the bacteria from the rats' blood. The rats whose blood had been filtered also had less inflammation in their lungs and other organs, suggesting they would be less prone to sepsis.
The researchers then tested whether the biospleen could handle the volume of blood in an average adult human - about 5 litres.
They ran human blood containing a mixture of bacteria and fungi through the biospleen at a rate of 1 litre per hour, and found that the device removed most of the pathogens within five hours.

Ingber said that the biospleen could also help to treat viral diseases such as HIV and Ebola, in which survival depends on lowering the amount of virus in the blood to a negligible level.