Engineered animal skin, hide, and leather comprising a plurality of layers of collagen formed by cultured animal collagen-producing (e.g., skin) cells. Layers may be formed by elongate multicellular bodies comprising a plurality of cultured animal cells that are adhered and/or cohered to one another; wherein the elongate multicellular bodies are arranged to form a substantially planar layer for use in formation of engineered animal skin, hide, and leather. Further described herein are methods of forming engineered animal skin, hide, and leather utilizing said layers of animal collagen-producing cells.

Described herein are engineered multilayered vascular tubes comprising at least one layer of differentiated adult fibroblasts, at least one layer of differentiated adult smooth muscle cells, wherein any layer further comprises differentiated adult endothelial cells, wherein said tubes have the following features: (a) a ratio of endothelial cells to smooth muscle cells of about 1:99 to about 45:55; (b) the tube is compliant; (c) the internal diameter of the tube is about 6 mm or smaller; (d) the length of the tube is up to about 30 cm; and (e) the thickness of the tube is substantially uniform along a region of the tube; provided that the engineered multilayered vascular tube is free of any pre-formed scaffold. Also described herein are methods of forming said tubes and uses for said tubes including methods for treating patients, comprising providing such a tube into to a patient in need thereof.

A microfabricated platform for mimicking the liver zonation and an evaluating method of zone-specific hepatotoxicity using the same is provided. The microfabricated platform for mimicking the liver zonation prepared according to the method of the present invention is divided into three zones of zone 1, zone 2 and zone 3 similarly to in vivo liver tissue and thus the zone-specific hepatotoxicity of a drug in the liver can be evaluated using the same. According to the present invention, the zone-specific hepatotoxicity results can be analyzed quantitatively by using image analysis, so that the platform of the present invention can be effectively used for in vitro screening of zone-specific hepatotoxicity.

An artificial skin culture container according to the present invention can solve the problems of the contraction of the dermal layer of artificial skin and the detachment thereof from the culture container, which result from an interaction between collagen and fibroblasts existing in the dermal layer of artificial skin during the production of the artificial skin, by using agar and hydrophobically modifying a portion of the agar. Therefore, the use of the culture container enables to stably culture artificial skin and produce artificial skin similar to the human skin. In addition, the artificial skin culture container of the present invention comprises agar, and thus a culture solution can be supplied through a side portion as well as a lower portion of the culture container, which allows to effectively culture artificial skin.

Structures and methods for tissue engineering include a multicellular body including a plurality of living cells. A plurality of multicellular bodies can be arranged in a pattern and allowed to fuse to form an engineered tissue. The arrangement can include filler bodies including a biocompatible material that resists migration and ingrowth of cells from the multicellular bodies and that is resistant to adherence of cells to it. Three-dimensional constructs can be assembled by printing or otherwise stacking the multicellular bodies and filler bodies such that there is direct contact between adjoining multicellular bodies, suitably along a contact area that has a substantial length. The direct contact between the multicellular bodies promotes efficient and reliable fusion. The increased contact area between adjoining multicellular bodies also promotes efficient and reliable fusion. Methods of producing multicellular bodies having characteristics that facilitate assembly of the three-dimensional constructs are also provided.

A polymer hydrogel having a polymer formed by the crosslinking reaction of a polymeric unit A according to formula (I),

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with a crosslinking unit B according to formula (II)

##STR00002##

and water, wherein n=100-10,000, preferable 250-2500, more preferable 500-1500; m=independently 2-10, preferably 3 or 4; FG is a functional moiety that can be covalently coupled to the complementary functional moiety F1 or F2 of the crosslinking unit (B); k=0.01-0.05; h=0, 1 or 2; the spacer is an organic moiety, having a main chain comprising at least two functional moieties F1 and F2, wherein the length of the crosslinker in the extended conformation as determined by molecular modeling (including spacer and functional groups F1 and F2) is between 2.5 and 12 nm, or wherein the length is between 20 and 80 atoms.

Provided are methods of controlling disassociation of cells from a carrier, compositions, and methods of collecting cells. The methods of controlling disassociation of cells from a carrier may include contacting a polymeric carrier with one or more digesting agents to disassociate at least a portion of a plurality of cells from the polymeric carrier. The polymeric carrier may be crosslinked with a crosslinker including at least one of a redox sensitive moiety, a UV light sensitive moiety, a pH sensitive moiety, and a temperature sensitive moiety.

Provided herein are methods and systems for bio-printing of three-dimensional organs and organoids. Also provided herein are bio-printed three-dimensional organs and organoids for use in the generation and/or the assessment of immunological products and/or immune responses. Also provided herein are methods and system for bio-printing three-dimensional matrices.

A structure for culturing cells includes growth medium regions on a surface of the structure. Each of the growth medium regions includes a growth medium surface configured to receive and promote growth in a cell that is being cultured. The structure includes a non-growth medium. The non-growth medium includes a non-growth medium surface configured to receive the cell that is being cultured.

Provided herein are methods and systems for bio-printing of three-dimensional organs and organoids. Also provided herein are bio-printed three-dimensional organs and organoids for use in the generation and/or the assessment of immunological products and/or immune responses. Also provided herein are methods and system for bio-printing three-dimensional matrices.