Image-Assisted Microvessel-on-a-Chip Platform for Studying Cancer Cell Transendothelial Migration Dynamics

Magda Gerigk,Cristina Bertulli,Duo Zhang,Thomas Müller,Nicholas Piano,Ye Liu,Tuomas J Knowles,Yan Yan Shery Huang

doi:10.1038/s41598-018-30776-0

Abstract

With the push to reduce in vivo approaches, the demand for microphysiological models that recapitulate the in vivo settings in vitro is dramatically increasing. Here, we present an extracellular matrix-integrated microfluidic chip with a rounded microvessel of ~100 µm in diameter. Our system displays favorable characteristics for broad user adaptation: simplified procedure for vessel creation, minimised use of reagents and cells, and the ability to couple live-cell imaging and image analysis to study dynamics of cell-microenvironment interactions in 3D. Using this platform, the dynamic process of single breast cancer cells (LM2-4175) exiting the vessel lumen into the surrounding extracellular matrix was tracked. Here, we show that the presence of endothelial lining significantly reduced the cancer exit events over the 15-hour imaging period: there were either no cancer cells exiting, or the fraction of spontaneous exits was positively correlated with the number of cancer cells in proximity to the endothelial barrier. The capability to map the z-position of individual cancer cells within a 3D vessel lumen enabled us to observe cancer cell transmigration ‘hot spot’ dynamically. We also suggest the variations in the microvessel qualities may lead to the two distinct types of cancer transmigration behaviour. Our findings provide a tractable in vitro model applicable to other areas of microvascular research.

Highlights

With the push to reduce in vivo approaches, the demand for microphysiological models that recapitulate the in vivo settings in vitro is dramatically increasing
A variety of techniques to fabricate 3D endothelial vessels inside microfluidic devices have been described, most research groups opt for polidimethylsiloxane (PDMS) molding combined with direct hydrogel injection, which provides an excellent base to study mechanistic processes associated with haematological diseases[7], or critical steps in cancer metastasis[8]
This study describes the design of an in vitro 3D microvessel which incorporates an endothelial extracellular matrix (ECM) interface

Summary

Introduction

With the push to reduce in vivo approaches, the demand for microphysiological models that recapitulate the in vivo settings in vitro is dramatically increasing. Our system displays favorable characteristics for broad user adaptation: simplified procedure for vessel creation, minimised use of reagents and cells, and the ability to couple live-cell imaging and image analysis to study dynamics of cell-microenvironment interactions in 3D Using this platform, the dynamic process of single breast cancer cells (LM2-4175) exiting the vessel lumen into the surrounding extracellular matrix was tracked. Exit of cancer cells from the blood vessel into secondary organs[9,10,11] have been replicated in microfluidic systems employing varying levels of complexity[12,13,14,15] These studies have begun to show that microfluidic platforms recapitulate the 3D in vivo conditions more closely than 2D models[16]. Though microfluidic systems provide a favorable platform to undertake such well-controlled experiments, statistical analysis of cellular dynamics is rare

Methods

Results

Discussion

Conclusion