Project description:Primary tissue-derived epithelial organoids are a physiologically relevant in vitro intestinal model that have been implemented for both basic research and drug development applications. The existing method of culturing intestinal organoids in surface-attached native extracellular matrix (ECM) hydrogel domes is not readily amenable to large-scale culture and contributes to culture heterogeneity. We have developed a method of culturing intestinal organoids within suspended basement membrane extract (BME) hydrogels of various geometries, which streamlines the protocol, increases the scalability, enables kinetic sampling, and improves culture uniformity without specialized equipment or additional expertise. We demonstrate the compatibility of this method with multiple culture formats, and provide examples of suspended BME hydrogel organoids in downstream applications: implementation in a medium-throughput drug screen and generation of Transwell monolayers for barrier evaluation. The suspended BME hydrogel culture method will allow intestinal organoids, and potentially other organoid types, to be used more widely and at higher throughputs than previously possible.
Project description:DNA barcodes can be used to identify single cells in a sequencing data space while optical codes can be used to track single live cells in an image data space. We have developed dual image and DNA (ID)-coding, which identifies individual single cells in both live image and sequencing data spaces. Samples provided here are relevant to proof-of-concept studies of ID-coding presented in the associated publication. DNA barcoded micro-particles were encapsulated in hydrogel droplets with or without single cells. The hydrogel droplets were then subjected to “single-droplet sequencing” where whole polyA-bearing nucleic acid components within a hydrogel droplet (i.e. mRNA from cells and synthetic DNA on beads) were concatenated by the same cell barcodes.
Project description:A new approach to sample preparation and enzymatic digestion in bottom-up proteomics has been developed using alginate-based hydrogel entrapment of enzymes. This hydrogel facilitates rapid and room-temperature digestions with multienzyme capabilities. Three methodologies were tested: within microcentrifuge tubes, in situ pipette tips, and automated robotic liquid handling. Factorial experimental design identified a 1 h, room temperature, pepsin–trypsin dual-enzyme digestion as optimal for sequence coverage and protein group identification, comparable to a gold-standard overnight proteomic protocol. This method promises significant advancements in proteomic analysis by enhancing reusability, speed, throughput, convenience, and cost-effectiveness, without hindering digestion efficiency.
Project description:End-stage liver diseases are an increasing health burden and liver transplantations are currently the only curative treatment option. Due to a lack of donor livers, alternative treatments are urgently needed. Human liver organoids are very promising for regenerative medicine, however, organoids are currently cultured in Matrigel, which is extracted from the extracellular matrix of the Engelbreth-Holm-Swarm mouse sarcoma. Matrigel is poorly defined, suffers from high batch-to-batch variability and is of murine origin, which limits clinical application of organoids. Here, a novel hydrogel based on polyisocyanopeptides (PIC) and laminin-111 is described for human liver organoid culture. PIC is a synthetic hydrogel with thermodynamic properties, making it easy to handle and very attractive for clinical applications. Organoids in an optimized PIC hydrogel proliferate at rates comparable to Matrigel; proliferation rates are stiffness-dependent, with lower stiffnesses being optimal for organoid proliferation. Moreover, organoids can be efficiently differentiated towards hepatocyte-like cells with key liver functions. This proliferation and differentiation potential can be maintained over at least 16 passages. Our results indicate that PIC is a promising material for human liver organoid culture and has the potential to be used in a variety of clinical applications including cell therapy and tissue engineering.
Project description:Explore the role of these hydrogels in wound healing, this study assessed the effects of both, Dersani Hydrogel with Alginate (DHA) and Dersani Hydrogel (DH), in human skin keratinocytes and fibroblasts gene expression profiles in a wound healing context. Sodium alginate (SA) and culture medium were also included as controls.
Project description:Delivery of therapeutic stem cells to treat bone tissue damage is a promising strategy that faces many hurdles to clinical translation. Among them is the design of a delivery vehicle which promotes desired cell behavior for new bone formation. In this work, we describe the use of an injectable microporous hydrogel, made of crosslinked gelatin microgels, for the encapsulation and delivery of human mesenchymal stem cells (MSCs) and compared it to a traditional nonporous injectable hydrogel. MSCs encapsulated in the microporous hydrogel showed rapid cell spreading with direct cell-cell connections whereas the MSCs in the nonporous hydrogel were entrapped by the surrounding polymer mesh and isolated from each other. Microporous hydrogel induced more robust osteogenic differentiation of MSCs and calcium mineral deposition than the nonporous hydrogel confirmed by alkaline phosphatase (ALP) assay and calcium assay. RNA-seq confirmed the upregulation of the genes and pathways that are associated with cell spreading and cell-cell connections, as well as the osteogenesis in the microporous hydrogel. These results demonstrate that the microgel-based injectable hydrogels can be useful tools for therapeutic cell delivery for bone tissue repair.