Project description:The vascularization of engineered tissues and organoids has remained a major unresolved challenge in regenerative medicine. While multiple approaches have been developed to vascularize in vitro tissues, it has thus far not been possible to generate perfusable vessels in sufficiently close proximity and at sufficient small scale to perfuse large de novo tissues. Here, we achieve the perfusion of multi-mm3 tissue constructs by generating perfusable synthetic capillary-scale 3D channels. Our 3D soft microfluidic strategy is uniquely enabled by a 3D-printable 2-photon-polymerizable hydrogel formulation, which allows for precise microvessel printing at scales below the diffusion limit. We demonstrate that these large-scale engineered tissues are viable, proliferative and exhibit complex morphogenesis during long-term in-vitro culture, while avoiding hypoxia and necrosis. We show by scRNAseq and immunohistochemistry that neural differentiation is significantly accelerated in perfused neural constructs. Additionally, we illustrate the versatility of this platform by demonstrating long-term perfusion of developing liver tissue. This fully synthetic vascularization platform opens the door to the generation of human tissue models at unprecedented scale and complexity.
Project description:Neutrophils play critical roles in modulating the immune response. However, neutrophils have a short circulating half life, are readily stimulated in vitro, and have low levels of cellular mRNA when compared to other blood leukocyte populations. All of these factors have made it difficult to evaluate neutrophils from clinical populations for molecular and functional studies. Here we present a robust methodology for rapidly isolating neutrophils directly from whole blood and develop âon- chipâ processing for mRNA and protein isolation for genomics and proteomics. We validate this device with an ex vivo stimulation experiment and demonstrate the ability of the device to discriminate subtle differences in the genomic and proteomic response of peripheral blood neutrophils to direct and indirect stimulation. Lastly, we implement this tool as part of a near patient blood processing system within a multi-center clinical study of the immune response to severe trauma and burn injury and demonstrate that this technique is easy to use by nurses and technical staff yielding excellent quality and sufficient quantity of mRNA for sensitive genomic readout of the host response to injury 1. Ex vivo Stimulation Studies: We assessed whether the relatively small number of isolated neutrophils captured by the microfluidics cassettes would impact the resulting genomic sensitivity and potential discriminatory genomic capabilities in response to various stimuli. To do this, we compared the genome-wide expression profile in neutrophils from 4 independent repeated experiements under three conditions - untimulated, ex vivo activation with either Escherichia coli lipopolysaccharide (LPS), or with granulocyte-macrophage colony-simulating factor (GM-CSF) and interferon-gamma (INF-g) (referred to as GM+I). In both protocols, whole blood was stimulated ex vivo24 to allow leukocyte and plasma protein interactions. 2. Inter-subject Reproducibility: To further ensure the reliability of the of the microfluidics cassette isolation method, we directly compared the gene expression of neutrophils captured in the microfluidics cassettes with neutrophils isolated using density centrifugation with Ficoll-dextran. We performed parallel neutrophil isolations using both methodologies from five different healthy volunteers and processed the cell lysates for microarray analysis using identical protocols.
Project description:The fungal toxin-encoding genes are highly upregulated in the vegetative mycelium upon challenge with the predator. Our recent studies in microfluidics have shown that latter induction is spatially restricted to parts of the vegetative mycelium that is in direct contact with the predator. In order to dissect the defensome of a multicellular fungus against a predator, here, we performed RNA - sequencing of mushroom Coprinopsis cinerea upon challenged with fungivorous nematode Aphelenchus avenae in Microfluidics device at three different time points. We analyzed hyphae that were collected from a microfluidics device where they have been in direct contact with or cultivated without A. avenae.
Project description:Human pericytes demonstrate multilineage differentiation potential, and their descendants participate in tissue homeostasis and repair. Increasing evidence from developmental biology and tissue engineering suggest that regional specification by tissue of origin exists among human pericytes.Here, we sought to define the differentiation of CD146+ human pericytes from skeletal and soft tissue sources. Uncultured CD146+CD31-CD45- pericytes were derived by fluorescent activated cell sorting from human periosteum, adipose, or dermal tissue. Periosteal CD146+CD31-CD45- cells retained canonical features of pericytes, including cell surface marker expression, multilineage differentiation potential, and paracrine induced tubulogenesis. Periosteal pericytes demonstrated a striking tendency to undergo osteoblastogenesis, while soft tissue pericytes did not in vitro or in vivo. Microarray analysis demonstrated enrichment in CXCR4 and BMP signaling among periosteal pericytes in comparison to their soft tissue pericyte counterparts. Signaling pathway manipulation of CXCR4 among soft tissue pericytes led to an increase in osteoblastogenesis and bone formation. In sum, skeletal and soft tissue pericytes differ in their relative lineage differentiation potential and ability to form bone. Plasticity exists, however, and manipulation of CXCR4 signaling pathway may ‘coax’ a soft tissue pericyte toward an osteoblastogenic cell fate.
Project description:A microfluidics technology was implemented to the immunoaffinity purification process of MHC peptides in Ligandomics/Immunopeptidomics. The thus purified HLA peptides were analysed by LCMS with the nanoElute LC and TimsTOF Pro Mass Spectrometer from Bruker. The aim of the microfluidics implementation was to improve the sensitivity and robustness while also reducing antibody and other material requirements in the immunoaffinity purification protocol.
Project description:We used microarrays to detail differential gene expression in perfused rat liver after 180 min under normo- and hypoosmotic condition.
Project description:We used microarrays to detail differential gene expression in perfused rat liver after 180 min under normo- and hypoosmotic condition.
Project description:Micro- and nanoscale patterned monolayers of plasmonic nanoparticles were fabricated by combining concepts from colloidal chemistry, self-assembly, and subtractive soft lithography. Leveraging chemical interactions between the capping ligands of pre-synthesized gold colloids and a polydimethylsiloxane stamp, we demonstrated patterning gold nanoparticles over centimeter-scale areas with a variety of micro- and nanoscale geometries, including islands, lines, and chiral structures (e.g., square spirals). By successfully achieving nanoscale manipulation over a wide range of substrates and patterns, we establish a powerful and straightforward strategy, nanoparticle chemical lift-off lithography (NP-CLL), for the economical and scalable fabrication of functional plasmonic materials with colloidal nanoparticles as building blocks, offering a transformative solution for designing next-generation plasmonic technologies.