Project Goal: To use novel and innovative tools to measure neutrophil activity in patients with ME/CFS, LongCovid and Post Treatment Lyme Disease Syndrome (PTLDS). Neutrophils are white blood cells that play a central role in allowing patients to manage bacterial, viral and fungal infections. The Harvard team performing the study has developed advanced microfluidic devices capable of measuring essential neutrophil functions tied to this antimicrobial activity – including how fast neutrophils obtained from a given patient can “swim” towards pathogens in the blood and successfully kill them. This could lead to development of a quick, finger-prick diagnostic test for pathogen-associated immune cell activity.

The microfluidic devices used by the team are, in simple terms, miniature mazes that track how well neutrophils can travel through tiny spaces. Blood collected from patients is immediately exposed to these mazes to measure exactly how neutrophils are acting in the body at the time of collection. Indeed, the mazes are so sensitive that they can detect if neutrophils from a given patient are responding to just one or two bacterial/viral organisms (this is important in conditions like PTLDS where small and difficult to identify organisms may drive symptoms). The microfluidic devices can also be adjusted to measure the activity of other immune cells in patients with ME/CFS, LongCovid and PTLDS, such as natural killer cells.

The team is additionally using similar tools to characterize neutrophil extracellular trap (NET) formation in patients’ blood. NETs are extensions of neutrophils that trap and digest pathogens.