Engineered tissues

Three-dimensional cell-laden photosensitive polymer hydrogels can be bioprinted in tissues of live animals, by bio-orthogonal two-photon cycloaddition and crosslinking of the polymers.

Cell-laden hydrogels can be patterned with algorithmically generated sacrificial dendritic vessel networks made of laser-sintered carbohydrate powders.

A robotically handled culture system using porcine gastrointestinal tissue explants for the high-throughput interrogation of the gastrointestinal tract predicts the absorption of oral drugs in the human gut better than Caco-2 Transwells.

This Review summarizes progress in the development of engineering strategies employed in reproductive science and medicine, with a focus on biomaterials and microfluidic approaches.

This Perspective summarizes the most recent developments in the bioprinting of cartilage, bone and skin for clinical applications, and discusses translational challenges and opportunities in the fabrication of complex 3D-printed tissues and organs.

Decellularized whole porcine livers revascularized with human endothelial cells and implanted heterotopically into immunosuppressed pigs whose spleens had been removed can sustain perfusion for up to 15 days.

A fast in vitro model of the formation of bone-like nodules, enabled by the retinoic-acid-mediated induction of the osteogenic differentiation of patient-derived induced pluripotent stem cells, recapitulates the osteogenesis-imperfecta phenotype.

Hydrogels incorporating human stromal cells and that after implantation in mice recruit cells from an orthotopic human tumour xenograft enable, after the injection of human immune cells, the study of the evolution of pre-metastatic niches.

Adult skeletal muscle, engineered from adult-rat myogenic cells, self-repairs after injury in vitro and when implanted in a mouse dorsal skinfold window-chamber model when the tissue incorporates rat or human macrophages.

Cardiac tissue engineered to enable the modulation of mechanical resistance to tissue contraction facilitates the modelling of genetic pathologies associated with the absence of a thick-filament accessory protein found in striated heart muscle.

Scale models of the human left ventricle made of tissue-engineered nanofibrous scaffolds and primary rat cardiomyocytes or human-stem-cell-derived cardiomyocytes enable the study of contractile function and the modelling of structural arrhythmia.

Hydrogels made from decellularized human brain tissue facilitate the direct conversion of primary mouse embryonic fibroblasts into induced neuronal cells that lead to therapeutic outcomes after transplantation in an animal model of ischaemic stroke.

A cell-culture method involving decellularized tissue scaffolds enables the spontaneous formation of cell colonies that phenotypically recapitulate in vivo organ-specific cancer metastases.

Culturing conditions affect the transcriptomic profiles of induced neuronal cells, and 3D co-cultures of induced neuronal cells and astrocytic cells can be rapidly generated from the same pool of human embryonic stem cells.

This Perspective argues that tissue-manufacturing approaches relying on directed self-organization will enable the production of functional tissues with complex biological features.

3D-printed grafts with geometrically designed and endothelialized vasculature rescue the perfusion of distal tissues in rodent models of hind limb ischaemia and myocardial infarction, preventing capillary loss, muscle atrophy and loss of function.

A comparison of the in vivo engraftment of scaffolds containing either an unassembled suspension of human vascular cells or an assembled network of them shows that non-inflammatory host neutrophils are indispensable mediators of vascularization.