Innovative Microfluidic System Enables Rapid, Label-Free Evaluation of Neutrophil Function in Sepsis Patients

Sepsis, a life-threatening condition caused by infection and immune system dysregulation, involves complex immune responses that are challenging to assess quickly and accurately. Neutrophils, a type of white blood cell critical to the immune defense, play a significant role in the progression of sepsis. However, current clinical tools fall short in their ability to simultaneously isolate these cells and evaluate their functional activity efficiently.

A team of researchers from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences and the First Affiliated Hospital of Anhui Medical University has developed a groundbreaking microfluidic platform that addresses these limitations. This innovative system allows for label-free sorting and functional analysis of neutrophils directly from small blood samples, making it a powerful tool for early diagnosis and monitoring.

The platform comprises two integrated components. The first is a cell-sorting chip (CS chip) capable of extracting white blood cells with over 80% purity and more than 90% viability from as little as 50 microliters of blood. The second component, a deformation and chemotaxis chip (CD² chip), evaluates neutrophil motility by measuring deformation time (T_D) and migration time (T_M). These two modules work in tandem within a single device, automating both cell sorting and functional assessment in approximately 30 minutes.

To ensure gentle handling of the cells and accurate measurements, the researchers optimized the device's structural design and employed COMSOL simulations to create smooth fluid flow conditions, preserving cell integrity. Clinical testing demonstrated that neutrophils from sepsis patients exhibit significantly impaired motility, characterized by prolonged T_D and T_M times, compared to cells from healthy individuals.

Furthermore, the team introduced a Neutrophil Motility and Function Index, combining the deformation and migration times into a single diagnostic parameter. This index showed excellent accuracy in distinguishing septic from healthy states and correlated strongly with established clinical markers.

This technology offers a rapid, label-free, and dynamic approach to assessing immune function, holding great promise for enhancing early diagnosis, personalized treatment, and real-time monitoring of sepsis. By providing detailed insights into neutrophil behavior, this platform could significantly improve clinical outcomes and deepen our understanding of immune dysregulation in sepsis.

Source: https://medicalxpress.com/news/2025-09-microfluidic-platform-free-neutrophil-function.html