Volumetric muscle loss (VML) injuries characterized by critical loss of skeletal muscle tissues result in severe functional impairment. Current treatments involving use of muscle grafts are limited by tissue availability and donor site morbidity. The present application relates to methods and composition matters for skeletal muscle healing and regeneration for a patient with volumetric muscle loss using a glycosaminoglycan-based hydrogel, wherein said hydrogel for skeletal muscle regeneration comprises functionalized hyaluronic acid (HA), functionalized chondroitin sulfate (CS) and poly(ethylene glycol) diacrylate (PEGDA), wherein said HA and said CS are cross-linked by said PEGDA.

A biocompatible scaffold construct may include a biocompatible hydrogel and at least one biomaterial microfiber strand wound to form a plurality of microfiber segments in proximity to one another and arranged in an organized configuration.

A biocompatible scaffold construct includes a plurality of collagen fiber strands, a first portion of which have been coated by a first biocompatible solution and, optionally, a second portion of which have been coated by a second biocompatible solution different than the first biocompatible solution. The coatings may include cells. And the scaffold is constructed on rotating frame collectors.

A scaffold-free microtissue is disclosed that includes one or more gold nanostructures linked to a functional moiety, wherein the functional moiety is one or more vasculogenic peptides, one or more anti-inflammatory peptides, one or more antiapoptotic peptides, one or more antinecrotic peptides, one or more antioxidant peptides, one or more oligonucleotides, one or more lipid particles, one or more phospholipid particles, one or more liposomes, one or more nanoliposomes, one or more microRNAs, or one or more siRNAs. The scaffold-free microtissue further includes a plurality of cardiac myocytes or cardiac myoblasts, which are conjugated to the one or more gold nanostructures, wherein the plurality of cardiac myocytes or cardiac myoblasts are arranged in a cluster. The scaffold-free microtissue further includes a plurality of fibroblasts, wherein the fibroblasts are arranged in at least one layer of fibroblasts that substantially surrounds the cluster of gold-nanostructure-conjugated cardiac myocytes or gold-nanostructure-conjugated cardiac myoblasts.

The present invention provides tissue equivalent scaffold structures and methods of production thereof. Such methods include providing a casting chamber comprising an elongate mould portion, axially disposing a lumen template within the elongate mould portion, and at least partly filling the casting chamber with a gel casting material comprising a matrix of fibrils or fibres and an interstitial fluid phase, such that a portion of the lumen template extends above the casting material. The fluid phase of the gel is allow to flow axially out of the elongate mould portion, in a restricted manner, thereby resulting in axial densification of the gel casting material to form a tissue equivalent tubular scaffold. Tissue equivalent scaffold structures according to the present invention are able to support cell populations both within the walls and on the surface of the construct. They have enhanced mechanical strength due to increased collagen density, and are customisable in terms of luminal diameter and wall thickness. They may find application in tubular tissue engineering.

A system and method for printing cells in a medium. A multi-dimensional printer, stably constructed of low-mass parts, can include a computer numerically controlled system that can enable motors driving delivery systems. The motors can include encoders that can enable achieving arbitrary resolution. The motors can drive ballscrews to enable linear motion of delivery systems, and the delivery systems can enable printing of a biological material in a pre-selected pattern in a petri dish. The petri dish can accommodate a medium such as a gel, and can further accommodate a vision system that can detect actual position and deflection of the delivery system needle. The printer can accommodate multiple delivery systems and therefore multiple needles of various sizes.

The present invention provides methods for cellular seeding onto three-dimensional fibroblast constructs, three-dimensional fibroblast constructs seeded with muscle cells, and uses therefore.

Provided herein are methods of culturing organized skeletal muscle tissue from precursor muscle cells by cyclically stretching and relaxing said muscle cells on a support in vitro for a time sufficient to produce said organized skeletal muscle tissue, including reseeding said organized skeletal muscle tissue by contacting additional precursor muscle cells to said organized skeletal muscle tissue on said solid support, and then repeating said step of cyclically stretching and relaxing said muscle cells in said support in vitro for time sufficient to enhance the density (i.e., increased number of nuclei and/or number of multinucleated cells) of said organized skeletal muscle tissue on said support.

A method may comprises bringing cells suspended in an aqueous medium into contact with a plurality of fragmented collagen pieces and, after the cells brought into contact with the plurality of fragmented collagen pieces and the plurality of fragmented collagen pieces are concentrated, culturing the cells brought into contact with the fragmented collagen pieces, with the plurality of fragmented collagen pieces, to form a three-dimensional tissue.

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.