High-throughput stem cell-based phenotypic screening through microniches.

As the field of tissue engineering develops, methods for screening combinations of signals for their effects on stem cell behavior are needed. We introduce a microgel-based screening platform for testing combinations of in situ-generated proteins on stem cell fate in ultrahigh-throughput. Compartmentalizing individual sets of growth factors was addressed by encapsulating aggregates of stable recombinant cell lines secreting individual glycoproteins into microgels through an on-chip polymerization.

Microfluidic production of bioactive fibrin micro-beads embedded in crosslinked collagen used as an injectable bulking agent for urinary incontinence treatment.

Unlabelled: Endoscopic injection of bulking agents has been widely used to treat urinary incontinence, often due to urethral sphincter complex insufficiency. The aim of the study was to develop a novel injectable bioactive collagen-fibrin bulking agent restoring long-term continence by functional muscle tissue regeneration. Fibrin micro-beads were engineered using a droplet microfluidic system.

Microfluidic Programming of Compositional Hydrogel Landscapes.

A droplet microfluidics strategy to rapidly synthesize, process, and screen up to hundreds of thousands of compositionally distinct synthetic hydrogels is presented. By programming the flow rates of multiple microfluidic inlet channels supplying individual hydrogel building blocks, microgel compositions and properties are systematically modulated. The use of fluorescent labels as proxies for the physical and chemical properties of the microgel permits the rapid screening and discovery of specific formulations through fluorescence microscopy or flow cytometry.

Cell-Instructive Microgels with Tailor-Made Physicochemical Properties.

A microfluidic in vitro cell encapsulation platform to systematically test the effects of microenvironmental parameters on cell fate in 3D is developed. Multiple cell types including fibroblasts, embryonic stem cells, and cancer cells are incorporated in enzymatically cross-linked poly(ethylene glycol)-based microgels having defined and tunable mechanical and biochemical properties. Furthermore, different approaches to prevent cell "escape" from the microcapsules are explored and shown to substantially enhance the potential of this technology.

Stem cell niche engineering through droplet microfluidics.

Stem cells reside in complex niches in which their behaviour is tightly regulated by various biochemical and biophysical signals. In order to unveil some of the crucial stem cell-niche interactions and expedite the implementation of stem cells in clinical and pharmaceutical applications, in vitro methodologies are being developed to reconstruct key features of stem cell niches. Recently, droplet-based microfluidics has emerged as a promising strategy to build stem cell niche models in a miniaturized and highly precise fashion.