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Biology subjects

Agley, C. C.

Publications and source records attributed to Agley, C. C..

2 recordsLinked to original sources

Microfluidic platform for live cell imaging of 3D cultures with clone retrieval

Combining live imaging with the ability to retrieve individual cells of interest remains a technical challenge. These combined methods are of particular interest when studying highly dynamic or transient, asynchronous or heterogeneous cell biological and developmental processes. Here we present a method to encapsulate live cells in a 3D hydrogel matrix, via droplet compartmentalisation. Using a small-scale screen, we optimised matrix conditions for the culture and multilineage differentiation of mouse embryonic stem (ES) cells. Moreover, we designed a custom microfluidic platform that is compatible with live imaging. With this platform we are able to retain or extract individual bead/droplets by media flow only, obviating the need for enzymatic cell removal from the platform. We show that we can differentiate mES cells, monitor reporter expression by live imaging, and retrieve individual droplets for functional assays, correlating reporter expression with functional response. Overall, we present a highly flexible 3D cell encapsulation and microfluidic platform that enables both monitoring of cellular dynamics and retrieval for molecular and functional assays.

bioengineering↗

StemBond hydrogels optimise the mechanical microenvironment for embryonic stem cells

Studies of mechanical signalling are typically performed by comparing cells cultured on soft and stiff hydrogel-based substrates. However, it is challenging to independently and robustly control both substrate stiffness and tethering of extracellular matrix (ECM) to substrates, making ECM tethering a potentially confounding variable in mechanical signalling investigations. Moreover, poor ECM tethering can lead to weak cell attachment. To address this, we developed StemBond hydrogels, a hydrogel formulation in which ECM tethering is stable and can be varied independently of stiffness. We show that soft StemBond hydrogels provide an optimal format for culturing embryonic stem (ES) cells. We find that soft StemBond substrates improve the homogeneity of ES cell populations, boost their self-renewal, and increase the efficiency of cellular reprogramming. Our findings underline how soft microenvironments impact mechanosensitive signalling pathways regulating self-renewal and differentiation, indicating that optimising the complete mechanical microenvironment will offer greater control over stem cell fate specification.

cell biology↗