Microfiltering Sepsis

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Ingber modeled the design in theory after the spleen, which contains molecules that bind to pathogens, ferrying them out of the body as blood flows through.

So far, the team has been able to filter a volume of blood comparable to that found in a premature baby within two hours. The researchers are currently working to increase the device's capacity and efficiency, and they plan to use more pairs of channels to increase the filtration rate. The Center for Integration of Medicine and Innovative Technology (CIMIT) recently awarded the team a $500,000 grant toward further developing the technology, and Ingber plans to use the funds to set up animal studies in the next year.

"We're going to try this approach in rabbits, because they are the same size as preemies, who often have life-threatening sepsis," says Ingber. "And we're hoping that if we can demonstrate survival in rabbits, we can quickly go to patients."

Ultimately, Ingber envisions incorporating the microfluidic device into a cartridge form, which can be snapped into any conventional hemofiltration or dialysis system.

Jeffrey Platt, a professor of surgery at the University of Michigan Medical School, says that one challenge in using such a device is anticipating the specific pathogen involved in a given case of sepsis. There are multiple infectious agents, bacterial and fungal, that could trigger septic shock, and researchers would have to devise different magnetically coated solutions for each pathogen. However, Platt says, the device may effectively treat other conditions outside of sepsis.

"The concept underlying the device is novel and interesting, and might ultimately find other applications, such as removal of malignant cells or cholesterol particles from the blood," says Platt. "Whether in fact it would find one or another use depends on what may be found when it is tested in whole animal systems."