Abstract: A composition includes a hydrogel that includes a plurality biodegradable natural polymer macromers crosslinked with a first agent and optionally a plurality of cells dispersed in the crosslinked macromers, the microgels are capable of being crosslinked with a second agent that is different than the first crosslinking agent.

Abstract: A composition includes a plurality of coacervate micro and/or nanodroplets of oxidized alginate and a methacrylated gelatin.

Abstract: A bioadhesive includes a crosslinked biodegradable hydrogel that includes a plurality of oxidized, acrylated or methacrylated, natural polymer.

Abstract: A bioadhesive includes a crosslinked biodegradable hydrogel that includes a plurality of oxidized, acrylated or methacrylated, natural polymer. Bioadhesives are natural or synthetic materials that can be used for soft tissue repair to create a seal preventing leakage of biological fluids or to reinforce anatomic integrity as an attractive alternative to sutures and staples. The most widely used bioadhesives are fibrin, cyanoacrylates, and albumin-glutaraldehyde bioadhesives.

Abstract: A method of modulating transdifferentiation of chondrocytes to osteoblast includes administering to the chondrocytes an agent that modulates GP130 receptor signaling and expression of at least one of Sox2, Oct4, or Nanog of the chondrocytes.

Abstract: A method of forming an insoluble native collagen fiber additive, includes soaking the decellularized tissue powder, which includes collagen fibers, in acidic or basic, salt solution, enzymatically dissociating the insoluble collagen fibers, and isolating insoluble native collagen fibers from the solution. The isolated insoluble collagen fibers can be used in cell aggregates and/or tissue constructs to provide three dimensional cell growth and/or adhesion.

Abstract: A composition includes a plurality of particulate coated hydrogel microparticles, each of the microparticles including a hydrogel inner core and a particulate shell defined by a plurality of solid nanoparticles, the particulate shell inhibiting aggregation of the microparticles in an aqueous medium and being permeable to allow release of agents from the hydrogel inner core.

Abstract: An elastomeric nanocomposite hydrogel includes first natural polymer macromers covalently crosslinked with second natural polymer macromer and physically crosslinked with a plurality of inorganic nanoparticles. The elastomeric nanocomposite hydrogel is cytocompatible, and, upon degradation, produce substantially non-toxic products.

Abstract: A cytocompatible hydrogel includes a plurality first polymer macromers linked to a plurality of second polymer macromers different than the first polymer macromers by a plurality of ?-hydroxythio-ether linkages, and a plurality of cells encapsulated in the hydrogel.

Abstract: A composition includes a plurality of coacervate micro and/or nanodroplets of oxidized alginate and a methacrylated gelatin.

Abstract: A method for forming a bioactive agent spatially patterned includes providing a photocrosslinkable hydrogel that includes a photocrosslinkable base polymer, photocrosslinkable bioactive agent coupling polymer macromers, and at least one bioactive agent that couples to the photocrosslinkable bioactive agent coupling polymer macromer, an selectively exposing discrete portions of the photocrosslinkable hydrogel to actinic radiation effective to initiate cross-linking of the base polymer and the bioactive agent coupling polymer macromers at the exposed portions.

Abstract: A composition includes a dual crosslinkable hydrogel that includes a plurality of polymer macromers, which are crosslinked with a first agent and a second agent different than the first agent, wherein the crosslinks formed using the second agent are reversible and repeatable to allow the mechanical properties of the hydrogel to be dynamically adjusted.

Abstract: An interpenetrating polymer network (IPN) structured hydrogel includes a crosslinked first natural polymer macromer with a first elasticity and an interpenetrating network of crosslinked second natural polymer macromers having a second elasticity higher than the first elasticity, the IPN structured hydrogel being cytocompatible, and, upon degradation, produce substantially non-toxic products.

Abstract: A tissue construct comprising includes a self-assembled, scaffold-free, high-density cell aggregate. The cell aggregate includes a plurality of cells and a plurality of biocompatible and biodegradable nanoparticles and/or microparticles that are incorporated within the cell aggregate. The nanoparticles and/or microparticles act as a bulking agent within the cell aggregate to increase the cell aggregate size and/or thickness and improve the mechanical properties of the cell aggregate allowing the cell aggregate to be readily manipulated and formed into tissue constructs with defined architectures.

Abstract: A composition includes a plurality of coacervate micro and/or nanodroplets of oxidized alginate and a methacrylated gelatin.

Abstract: A tissue construct comprising includes a self-assembled, scaffold-free, high-density cell aggregate. The cell aggregate includes a plurality of cells and a plurality of biocompatible and degradable nanoparticles and/or microparticles that are incorporated within the cell aggregate. The nanoparticles and/or microparticles act as a bulking agent and/or provide bioactive agents or signals within the cell aggregate to increase the cell aggregate size and/or thickness and improve the mechanical properties of the cell aggregate and/or regulate cell function within the aggregate allowing the cell aggregate to be readily manipulated and formed into tissue constructs with defined architectures and potential tissue specific functionality.

Abstract: A modular engineered tissue construct includes a plurality of fused self-assembled, scaffold-free, high-density cell aggregates. At least one cell aggregate includes a plurality of cells and a plurality of biocompatible and biodegradable nanoparticles and/or microparticles that are incorporated within the cell aggregates. The nanoparticles and/or microparticles acting as a bulking agent within the cell aggregate to increase the cell aggregate size and/or thickness and improve the mechanical properties of the cell aggregate as well as to deliver bioactive agents.

Abstract: A modular engineered tissue construct includes a plurality of fused self-assembled, scaffold-free, high-density cell aggregates. At least one cell aggregate includes a plurality of cells and a plurality of biocompatible and biodegradable nanoparticles and/or microparticles that are incorporated within the cell aggregates. The nanoparticles and/or microparticles acting as a bulking agent within the cell aggregate to increase the cell aggregate size and/or thickness and improve the mechanical properties of the cell aggregate as well as to deliver bioactive agents.

Abstract: A photocrosslinked biodegradable hydrogel includes a plurality of natural polymer macromers cross-linked with a plurality of hydrolyzable acrylate cross-links. The hydrogel is cytocompatible and produces substantially non-toxic products upon degradation.

Abstract: A bioadhesive includes a crosslinked biodegradable hydrogel that includes a plurality of oxidized, acrylated or methacrylated, natural polymer. Bioadhesives are natural or synthetic materials that can be used for soft tissue repair to create a seal preventing leakage of biological fluids or to reinforce anatomic integrity as an attractive alternative to sutures and staples. The most widely used bioadhesives are fibrin, cyanoacrylates, and albumin-glutaraldehyde bioadhesives.