A prosthetic heart valve provided herein can include a cultured cell tissue leaflet. In some cases, a prosthetic heart valve can include a plurality of leaflets secured together and retained within the expandable tubular member. The cultured cell tissue can be obtained by culturing fibroblast cells, smooth muscle cells, or a combination thereof to form a sheet of cultured cells and chemically cross-linking the fibroblast cells while under tension. In some cases, the cultured cell tissue can be radially tensioned. In some cases, the cultured cell tissue can be bi-axially tensioned.

Devices, systems, and techniques are described for printing pre-aligned microtissues into larger tissue constructs. For example, a method of printing a tissue construct includes aligning cells in a first direction to create pre-aligned microtissues, suspending the pre-aligned microtissues in a liquid to create a bioink, and depositing the pre-aligned microtissues in a second direction to create the tissue construct.

Differentiation and stability of neural stem cells can be enhanced by in vitro or in vivo culturing with one or more extracellular matrix (ECM) compositions, such as collagen I, IV, laminin and/or a heparan sulfate proteoglycan. In one aspect of the invention, adult mammalian enteric neuronal progenitor cells can be induced to differentiate on various substrates derived from components or combinations of neural ECM compositions. Collagen I and IV supported neuronal differentiation and extensive glial differentiation individually and in combination. Addition of laminin or heparan sulfate to collagen substrates unexpectedly improved neuronal differentiation, increasing neuron number, branching of neuronal processes, and initiation of neuronal network formation. In another aspect, neuronal subtype differentiation was affected by varying ECM compositions in hydrogels overlaid on intestinal smooth muscle sheets. The matrix compositions of the present invention can be used to tissue engineer transplantable innervated GI smooth muscle constructs to remedy aganglionic disorders.

Disclosed herein are methods and compositions for stimulating angiogenesis, using cells descended from marrow adherent stromal cells that have been transfected with sequences encoding a Notch intracellular domain. Applications of these methods and compositions include treatment of ischemic disorders such as stroke.

Engineered multilevel cell sheet-derived blood vessels and methods of preparing and using them are disclosed. Blood vessels are generated by wrapping cell sheets around a rod-like device, such as an angiocath needle, to form a tube, which is stabilized with a cyanoacrylate membrane or fibrin glue followed by endothelialization. Such engineered blood vessels can be implanted in tissue and used in vascular surgery as vascular bypass or interposition grafts as well as for vascularization and perfusion of tissue or organs prior to transplant.

The presently disclosed subject matter provides systems and methods for producing a three-dimensional model of a human cervix. A microdevice is provided for culturing human cervical cells. The microdevice can include an upper microchannel including live ectocervical epithelial cells. The microdevice can include a lower microchannel including a first parallel lane and a second parallel lane including stromal media. The first and the second parallel lanes can be lined with live vascular endothelial cells. The lower microchannel can include a third parallel lane including uterine fibroblasts and live smooth muscle cells embedded in hydrogel. The first, second, and third lanes of the lower microchannel can be separated by protrusion structures. The third parallel lane can be positioned in the lower microchannel in between the first and the second parallel lanes. The microdevice can further include a porous membrane positioned in between the upper microchannel and the lower microchannel.

Methods are disclosed for forming tissue engineered, tubular gut-sphincter complexes from intestinal circular smooth muscle cells, sphincteric smooth muscle cells and enteric neural progenitor cells. The intestinal smooth muscle cells and neural progenitor cells can be seeded on a mold with a surface texture that induces longitudinal alignment of the intestinal smooth muscle cells and co-cultured until an innervated aligned smooth muscle sheet is obtained. The innervated smooth muscle sheet can then be wrapped around a tubular scaffold to form an intestinal tissue construct. Additionally, the sphincteric smooth muscle cells and additional enteric neural progenitor cells can be mixed in a biocompatiable gel solution, and the gel and admixed cells applied to a mold having a central post such that the sphinteric smooth muscle and neural progenitor cells can be cultured to form an innervated sphincter construct around the mold post. This innervated sphincter construct can also be transferred to the tubular scaffold such that the intestinal tissue construct and sphincter construct contact each other, and the resulting combined sphincter and intestinal tissue constructs can be further cultured about the scaffold until a unified tubular gut-sphincter complex is obtained.

The presently disclosed subject matter provides systems and methods for producing a three-dimensional model of a human cervix. A microdevice is provided for culturing human cervical cells. The microdevice can include an upper microchannel including live ectocervical epithelial cells. The microdevice can include a lower microchannel including a first parallel lane and a second parallel lane including stromal media. The first and the second parallel lanes can be lined with live vascular endothelial cells. The lower microchannel can include a third parallel lane including uterine fibroblasts and live smooth muscle cells embedded in hydrogel. The first, second, and third lanes of the lower microchannel can be separated by protrusion structures. The third parallel lane can be positioned in the lower microchannel in between the first and the second parallel lanes. The microdevice can further include a porous membrane positioned in between the upper microchannel and the lower microchannel.

Devices, systems, and techniques are described for printing pre-aligned microtissues into larger tissue constructs. For example, a method of printing a tissue construct includes aligning cells in a first direction to create pre-aligned microtissues, suspending the pre-aligned microtissues in a liquid to create a bioink, and depositing the pre-aligned microtissues in a second direction to create the tissue construct.

Methods of generating an innervated muscle structures are disclosed as well as bioengineered structures for tissue repair or regeneration. The methods can include the steps of obtaining populations of smooth muscle cells and neuronal progenitor cells and then seeding the cells together onto a matrix material, followed by culturing the seeded cells to form an innervated smooth muscle cell construct of directionally oriented smooth muscle cells. In one embodiment, the neuronal progenitor cells can be seeded first as neurospheres in a biocompatiable solution, e.g., a collagen/laminin solution, and allowed to gel. Next, a second suspension of smooth muscle cells can be deposited as separate layer. Multiple layer structures of alternating muscle or neuron composition can also be formed in this manner. Differentiation of the neuronal progenitor cells can be induced by exposure to a differentiation medium, such as Neurobasal A medium and/or exposure to a differentiating agent, such as B-27 supplement. The innervated muscle structures can be disposed around a tubular scaffold, e.g., a chitosan-containing tube and further cultured to form tubular, bioengineered structures and two or more innervated muscle structures can be joined together to form an elongate composite structure.