11 research outputs found
Microfabricated blood vessels undergo neoangiogenesis
The greatest ambition and promise of tissue engineering is to manufacture human organs. Before âmade-to- measureâ tissues can become a reality [1-3], however, three-dimensional tissues must be reconstructed and characterized. The current inability to manufacture operational vasculature has limited the growth of engineered tissues. Here, free-standing, small diameter blood vessels with organized cell layers that recapitulate normal biological functionality are fabricated using microfluidic technology. Over time in culture, the endothelial cells form a monolayer on the luminal wall and remodel the scaffold with human extracellular matrix proteins. After integration into three-dimensional gels containing fibroblasts, the microvessels sprout and generate extended hollow branches that anastomose with neighboring capillaries to form a network. Both the microfabricated vessels and the extended sprouts support perfusion of fluids and particles. The ability to create cellularized microvessels that can be designed with a diameter of choice, produced by the meter, and undergo angiogenesis and anastomoses will be an extremely valuable tool for vascularization of engineered tissues. To summarize, ultraviolet (UV) photocross linkable poly(ethylene glycol) and gelatin methacrylate polymers used in combination with sheathflow microfluidics allow for the fabrication of small diameter blood vessels which undergo neoangiogenesis as well as other developmental processes associated with normal human blood vessel maturation. Once mature, these vessels can be embedded; perfused; cryogenically stored and respond to stimuli such as chemokines and shear stresses to mimic native human blood vessels. The applications range from tissue-on-chip systems for drug screening, characterization of normal and pathologic processes, and creation and characterization of engineered tissues for organ repair
Affinity purification of bacterial outer membrane vesicles (OMVs) utilizing a His-tag mutant
To facilitate the rapid purification of bacterial outer membrane vesicles (OMVs), we developed two plasmid constructs that utilize a truncated, transmembrane protein to present an exterior histidine repeat sequence. We chose OmpA, a highly abundant porin protein, as the protein scaffold and utilized the lac promoter to allow for inducible control of the epitope-presenting construct. OMVs containing mutant OmpA-His6 were purified directly from Escherichia coli culture media on an immobilized metal affinity chromatography (IMAC) Ni-NTA resin. This enabling technology can be combined with other molecular tools directed at OMV packaging to facilitate the separation of modified/cargo-loaded OMV from their wt counterparts. In addition to numerous applications in the pharmaceutical and environmental remediation industries, this technology can be utilized to enhance basic research capabilities in the area of elucidating endogenous OMV function
Microfabricated blood vessels undergo neoangiogenesis
The greatest ambition and promise of tissue engineering is to manufacture human organs. Before âmade-to- measureâ tissues can become a reality [1-3], however, three-dimensional tissues must be reconstructed and characterized. The current inability to manufacture operational vasculature has limited the growth of engineered tissues. Here, free-standing, small diameter blood vessels with organized cell layers that recapitulate normal biological functionality are fabricated using microfluidic technology. Over time in culture, the endothelial cells form a monolayer on the luminal wall and remodel the scaffold with human extracellular matrix proteins. After integration into three-dimensional gels containing fibroblasts, the microvessels sprout and generate extended hollow branches that anastomose with neighboring capillaries to form a network. Both the microfabricated vessels and the extended sprouts support perfusion of fluids and particles. The ability to create cellularized microvessels that can be designed with a diameter of choice, produced by the meter, and undergo angiogenesis and anastomoses will be an extremely valuable tool for vascularization of engineered tissues. To summarize, ultraviolet (UV) photocross linkable poly(ethylene glycol) and gelatin methacrylate polymers used in combination with sheathflow microfluidics allow for the fabrication of small diameter blood vessels which undergo neoangiogenesis as well as other developmental processes associated with normal human blood vessel maturation. Once mature, these vessels can be embedded; perfused; cryogenically stored and respond to stimuli such as chemokines and shear stresses to mimic native human blood vessels. The applications range from tissue-on-chip systems for drug screening, characterization of normal and pathologic processes, and creation and characterization of engineered tissues for organ repair
âData characterizing microfabricated human blood vessels created via hydrodynamic focusingâ
This data article provides further detailed information related to our research article titled âMicrofabricated Blood Vessels Undergo Neovascularizationâ (DiVito et al., 2017) [1], in which we report fabrication of human blood vessels using hydrodynamic focusing (HDF). Hydrodynamic focusing with advection inducing chevrons were used in concert to encase one fluid stream within another, shaping the inner core fluid into âbullseye-likeâ cross-sections that were preserved through click photochemistry producing streams of cellularized hollow 3-dimensional assemblies, such as human blood vessels (Daniele et al., 2015a, 2015b, 2014, 2016; Roberts et al., 2016) [2â6]. Applications for fabricated blood vessels span general tissue engineering to organ-on-chip technologies, with specific utility in in vitro drug delivery and pharmacodynamics studies. Here, we report data regarding the construction of blood vessels including cellular composition and cell positioning within the engineered vascular construct as well as functional aspects of the tissues