Related Experiment Video
Updated: Jun 18, 2025
Simultaneous Imaging of Microglial Dynamics and Neuronal Activity in Awake Mice
Published on: August 23, 2022
A programmable microfluidic platform to monitor calcium dynamics in microglia during inflammation
Adam Shebindu1,2, Durga Kaveti1, Linda Umutoni1
1Department of Bioengineering, University of Texas at Dallas, Richardson, TX 75080 USA.
Abstract:
Neuroinflammation is characterized by the elevation of cytokines and adenosine triphosphate (ATP), which in turn activates microglia. These immunoregulatory molecules typically form gradients in vivo, which significantly influence microglial behaviors such as increasing calcium signaling, migration, phagocytosis, and cytokine secretion. Quantifying microglial calcium signaling in the context of inflammation holds the potential for developing precise therapeutic strategies for neurological diseases. However, the current calcium imaging systems are technically challenging to operate, necessitate large volumes of expensive reagents and cells, and model immunoregulatory molecules as uniform concentrations, failing to accurately replicate the in vivo microenvironment. In this study, we introduce a novel calcium monitoring micro-total analysis system (CAM-μTAS) designed to quantify calcium dynamics in microglia (BV2 cells) within defined cytokine gradients. Leveraging programmable pneumatically actuated lifting gate microvalve arrays and a Quake valve, CAM-μTAS delivers cytokine gradients to microglia, mimicking neuroinflammation. Our device automates sample handling and cell culture, enabling rapid media changes in just 1.5 s, thus streamlining the experimental workflow. By analyzing BV2 calcium transient latency to peak, we demonstrate location-dependent microglial activation patterns based on cytokine and ATP gradients, offering insights contrasting those of non-gradient-based perfusion systems. By harnessing advancements in microsystem technology to quantify calcium dynamics, we can construct simplified human models of neurological disorders, unravel the intricate mechanisms of cell-cell signaling, and conduct robust evaluations of novel therapeutics.
Insights
Researchers developed a novel microfluidic system to precisely measure microglial calcium signaling under simulated neuroinflammation. This system accurately models in vivo conditions, revealing location-dependent microglial activation patterns for better therapeutic development.
Area of Science:
- Neuroscience
- Cell Biology
- Biomedical Engineering
Background:
- Neuroinflammation involves elevated cytokines and ATP, activating microglia and influencing their behavior via molecular gradients.
- Current calcium imaging systems struggle to replicate in vivo microenvironments and are resource-intensive.
- Accurate quantification of microglial calcium signaling is crucial for developing neurological disease therapeutics.
Purpose of the Study:
- To introduce a novel calcium monitoring micro-total analysis system (CAM-μTAS) for quantifying microglial calcium dynamics.
- To mimic in vivo neuroinflammatory conditions by creating defined cytokine gradients.
- To analyze location-dependent microglial activation patterns in response to these gradients.
Main Methods:
- Development of a CAM-μTAS utilizing microvalve arrays and a Quake valve for precise gradient generation.
- Automated sample handling and rapid media exchange (1.5s) for streamlined experiments.
- Quantification of BV2 cell calcium transient latency to peak in response to cytokine and ATP gradients.
Main Results:
- Demonstrated the ability of CAM-μTAS to generate and maintain cytokine gradients, mimicking neuroinflammation.
- Observed and quantified location-dependent microglial activation patterns based on gradient exposure.
- Showcased automated, rapid media exchange capabilities for efficient experimental workflows.
Conclusions:
- CAM-μTAS provides a more accurate model of the in vivo microenvironment for studying microglial responses.
- The system reveals novel insights into location-dependent microglial activation, contrasting traditional methods.
- This technology facilitates the development of human models for neurological disorders and therapeutic evaluations.
