Bacteria-laden microgels as autonomous three-dimensional environments for stem cell engineering

• Main Authors: K. Witte, A. Rodrigo-Navarro, M. Salmeron-Sanchez
• Format: Article
• Language: English
• Published: Elsevier 2019-03-01
• Series: Materials Today Bio
• Online Access: http://www.sciencedirect.com/science/article/pii/S2590006419300092

A one-step microfluidic system is developed in this study which enables the encapsulation of stem cells and genetically engineered non-pathogenic bacteria into a so-called three-dimensional (3D) pearl lace–like microgel of alginate with high level of monodispersity and cell viability. The alginate-based microgel constitutes living materials that control stem cell differentiation in either an autonomous or heteronomous manner. The bacteria (Lactococcus lactis) encapsulated within the construct surface display adhesion fragments (III7-10 fragment of human fibronectin) for integrin binding while secreting growth factors (recombinant human bone morphogenetic protein-2) to induce osteogenic differentiation of human bone marrow–derived mesenchymal stem cells. We concentrate on interlinked pearl lace microgels that enabled us to prototype a low-cost 3D bioprinting platform with highly tunable properties. Keywords: Droplet-based microfluidics, Bioprinting, Engineered bacteria, Cell engineering, Living materials, Stem cells