Electrical Stimulation Promotes the Vascularization and Functionalization of an Engineered Biomimetic Human Cardiac Tissue.

The formation of multiscale vascular networks is essential for the in vitro construction of large-scale biomimetic cardiac tissues/organs. Although a variety of bioprinting processes have been developed to achieve the construction of mesoscale and large-scale blood vessels, the formation of microvascular networks still mainly depends on the self-assembly behavior of endothelial cells (ECs), which is inefficient and demanding without appropriate stimulus. To address this problem, the elongation and connection of endothelial cells in engineered cardiac tissue (ECT) are sought to promote by electrical stimulation (ES) to achieve vascularization.

Creating a semi-opened micro-cavity ovary through sacrificial microspheres as an model for discovering the potential effect of ovarian toxic agents.

The bio-engineered ovary is an essential technology for treating female infertility. Especially the development of relevant models could be a critical step in a drug study. Herein, we develop a semi-opened culturing system (SOCS) strategy that maintains a 3D structure of follicles during the culture.

Expanding Embedded 3D Bioprinting Capability for Engineering Complex Organs with Freeform Vascular Networks.

Creating functional tissues and organs in vitro on demand is a major goal in biofabrication, but the ability to replicate the external geometry of specific organs and their internal structures such as blood vessels simultaneously remains one of the greatest impediments. Here, this limitation is addressed by developing a generalizable bioprinting strategy of sequential printing in a reversible ink template (SPIRIT). It is demonstrated that this microgel-based biphasic (MB) bioink can be used as both an excellent bioink and a suspension medium that supports embedded 3D printing due to its shear-thinning and self-healing behavior.

Study of paraquat-induced pulmonary fibrosis using biomimetic micro-lung chips.

Paraquat (PQ) poisoning induces pulmonary fibrosis. The pathogenesis of pulmonary fibrosis is complex, which has prevented the development of specific treatments. Pulmonary fibrosis shows several characteristics including epithelial-mesenchymal transition (EMT), fibroblast activation, and extracellular matrix (ECM) deposition.

3D Bioprinted GelMA-Nanoclay Hydrogels Induce Colorectal Cancer Stem Cells Through Activating Wnt/β-Catenin Signaling.

Cancer stem cells (CSCs) are a rare cell population in tumors that are responsible for tumor recurrence and metastasis. They are a priority as therapeutic targets, however, assays targeting CSCs have been limited by expanding and maintaining CSCs in vitro. Here, the authors find that gelatin methacryloyl (GelMA)-nanoclay hybrid hydrogels can induce and enrich colorectal CSCs assisted by three-dimensional (3D) bioprinting.

Dual cure (thermal/photo) composite hydrogel derived from chitosan/collagen for in situ 3D bioprinting.

In situ 3D printing technologies is a new frontier for highly personalized medicine, which requires suitable bioink with rheology, biocompatibility, and gelation kinetics to support the right shape and mechanical properties of the printed construct. To this end, a facile design of thermo/photo dual cure composite hydrogel was proposed using MHBC and soluble collagen in this study. M/C composite hydrogel exhibited rapid thermo-induced sol-gel transition and contraction, tunable mechanical properties, proper microstructure and biodegradability for 3D cell culture, as well as improve cyto-compatibility, all of which were dependent upon the methacrylation degree of MHBC and M/C ratios.

Rapid Fabrication of Cell-Laden Microfibers for Construction of Aligned Biomimetic Tissue.

Bottom-up engineering of tissue constructs is being rapidly developed and broadly applied in biomanufacturing. As one type of building block, cell-laden microfibers are promising for reconstruction of oriented structures and functions of linear tissues, such as skeletal muscles, myocardia, and spinal cord tissues. Herein, we propose wet-spinning method with agitating collection, wherein alginate-based material is extruded into an agitated CaCl bath with a magnetic rotor acting as the microfiber collector.

Optimizing Bifurcated Channels within an Anisotropic Scaffold for Engineering Vascularized Oriented Tissues.

Despite progress in engineering both vascularized tissues and oriented tissues, the fabrication of 3D vascularized oriented tissues remains a challenge due to an inability to successfully integrate vascular and anisotropic structures that can support mass transfer and guide cell alignment, respectively. More importantly, there is a lack of an effective approach to guiding the scaffold design bearing both structural features. Here, an approach is presented to optimize the bifurcated channels within an anisotropic scaffold based on oxygen transport simulation and biological experiments.