Characterizing asthma from a drop of blood using neutrophil chemotaxis

Asthma is a chronic inflammatory disorder that is notoriously difficult to diagnose, characterize, and properly treat with tests that are available to clinicians today. Therefore, clinicians would benefit from additional tools that objectively characterize asthma in patients. In this work, we describe a handheld microfluidic device that discriminates asthma from allergic rhinitis patients based on neutrophil function—an inflammatory cell that has been implicated in the pathogenesis of asthma. The device can sort neutrophils from a drop of whole blood within minutes, and was used in a clinical setting to characterize asthmatic and nonasthmatic patients. This technology provides a new tool for clinicians to characterize asthma based on cellular function.