A novel microfluidics chip developed by researchers at Massachusetts General Hospital (MGH) will let doctors examine how white blood cells called neutrophils help the body cope with burns and other traumatic injuries. It may also shed light on why the immune system sometimes spirals out of control, resulting in dangerous inflammation.

The chip lets scientists do something they've never before been able to do: quickly and easily capture neutrophils from a small volume of blood. In the long term, scientists hope to use this technology to predict which patients are most likely to develop serious infections after an injury and therefore need the most aggressive treatment. "People have been looking for biomarkers for injury and sepsis [blood poisoning] for a long time," says Steven Calvano, a researcher at Robert Wood Johnson Medical School. Calvano, who was not directly involved in the project, says, "This could be an extremely valuable clinical tool."

Damage to the skin's protective barrier, like the kind that occurs with traumatic injuries and severe burns, makes patients dangerously susceptible to infection. Neutrophils, the most abundant white blood cell in the body, are one of the immune system's first responders. They rush to the site of damage, where they devour bacteria and other invaders.

Recent research suggests that these cells also play a subtle role in the immune system, helping to regulate the immune response. An overreaction of the immune system after injury can cause systemic inflammation, which can be just as dangerous as the initial infection or damage. So if researchers can get a better picture of how these cells behave, that could lead to new drug targets to prevent or treat sepsis and inflammation. "Regulation of these cells is really the key to be able to target and change the overall response," says Carol Miller-Graziano, director of the Immunobiology and Stress Response Laboratories at the University of Rochester Medical Center. Miller-Graziano took part in the MGH project.

Until now, isolating these cells from blood has been lengthy and technically challenging. But a novel microfluidics chip developed by Ken Kotz and collaborators at the Center for Engineering in Medicine at MGH is changing that. In a study published online last week in the journal Nature Medicine, researchers showed that the device could capture the cells as effectively as traditional methods but in much less time. They also showed that a small volume of blood--150 microliters--generates enough cells for later analysis. The research is part of a large multicenter grant, funded by the National Institutes of Health, to better understand inflammation and how the body responds to injury.