Investigating How All-Trans Retinoic Acid Polycaprolactone (atRA-PCL) Microparticles Alter the Material Properties of 3D Printed Fibrin Constructs.

The 3D printing of human tissue constructs requires carefully designed bioinks to support the growth and function of cells. Here it is shown that an additional parameter is how drug-releasing microparticles affect the material properties of the scaffold. A microfluidic platform is used to create all-trans retinoic acid (atRA) polycaprolactone (PCL) microparticles with a high encapsulation efficiency (85.

3D Bioprinting a Novel Skin Co-Culture Model Using Human Keratinocytes and Fibroblasts.

3D bioprinting can generate the organized structures found in human skin for a variety of biological, medical, and pharmaceutical applications. Challenges in bioprinting skin include printing different types of cells in the same construct while maintaining their viability, which depends on the type of bioprinter and bioinks used. This study evaluated a novel 3D bioprinted skin model containing human keratinocytes (HEKa) and human dermal fibroblasts (HDF) in co-culture (CC) using a high-viscosity fibrin-based bioink produced using the BioX extrusion-based bioprinter.

Uniform block copolymer nanofibers for the delivery of paclitaxel in 2D and 3D glioblastoma tumor models.

Cancer treatment has transformed in recent years, with the introduction of immunotherapy providing substantial improvements in prognoses for certain cancers. However, traditional small molecule chemotherapeutics remain the major frontline of defence, and improving their delivery to solid tumors is of utmost importance for improving potency and reducing side effects. Here, length-controlled one-dimensional seed nanofibers ( 25 nm, = 1.

Tailored-Biomaterials Based Potential Strategies for Cardiovascular Disease.

Cardiovascular disease is a significant health concern worldwide, and varied effective treatment and prevention methods have been developed. Among these, tailored biomaterials-based strategies such as stents, scaffolds, patches, and drug delivery systems have emerged as a promising avenue. These devices are designed to match the mechanical and biological mechanisms of the cardiovascular system, ensuring optimal performance and compatibility.

Bioprinting functional neural networks.

3D printing human tissue models derived from stem cells provides an increasingly popular tissue engineering strategy for probing biological questions. Here Yan et al. demonstrate how this technology can be used to model mature human neural tissues with functional neural networks in healthy and disease states.

Modeling the neuroimmune system in Alzheimer's and Parkinson's diseases.

Parkinson's disease (PD) and Alzheimer's disease (AD) are neurodegenerative disorders caused by the interaction of genetic, environmental, and familial factors. These diseases have distinct pathologies and symptoms that are linked to specific cell populations in the brain. Notably, the immune system has been implicated in both diseases, with a particular focus on the dysfunction of microglia, the brain's resident immune cells, contributing to neuronal loss and exacerbating symptoms.

3D-bioprinted cardiac tissues and their potential for disease modeling.

Heart diseases cause over 17.9 million total deaths globally, making them the leading source of mortality. The aim of this review is to describe the characteristic mechanical, chemical and cellular properties of human cardiac tissue and how these properties can be mimicked in 3D bioprinted tissues.

The Impact of Biomaterial Surface Properties on Engineering Neural Tissue for Spinal Cord Regeneration.

Tissue engineering for spinal cord injury (SCI) remains a complex and challenging task. Biomaterial scaffolds have been suggested as a potential solution for supporting cell survival and differentiation at the injury site. However, different biomaterials display multiple properties that significantly impact neural tissue at a cellular level.

3D bioprinting for organ and organoid models and disease modeling.

Introduction: 3D printing, a versatile additive manufacturing technique, has diverse applications ranging from transportation, rapid prototyping, clean energy, and medical devices.

Areas Covered: The authors focus on how 3D printing technology can enhance the drug discovery process through automating tissue production that enables high-throughput screening of potential drug candidates. They also discuss how the 3D bioprinting process works and what considerations to address when using this technology to generate cell laden constructs for drug screening as well as the outputs from such assays necessary for determining the efficacy of potential drug candidates.

3D bioprinting patient-derived induced pluripotent stem cell models of Alzheimer's disease using a smart bioink.

Background: Alzheimer's disease (AD), a progressive neurodegenerative disorder, is becoming increasingly prevalent as our population ages. It is characterized by the buildup of amyloid beta plaques and neurofibrillary tangles containing hyperphosphorylated-tau. The current treatments for AD do not prevent the long-term progression of the disease and pre-clinical models often do not accurately represent its complexity.

Protocol for 3D Bioprinting Mesenchymal Stem Cell-derived Neural Tissues Using a Fibrin-based Bioink.

Three-dimensional bioprinting utilizes additive manufacturing processes that combine cells and a bioink to create living tissue models that mimic tissues found in vivo. Stem cells can regenerate and differentiate into specialized cell types, making them valuable for research concerning degenerative diseases and their potential treatments. 3D bioprinting stem cell-derived tissues have an advantage over other cell types because they can be expanded in large quantities and then differentiated to multiple cell types.

hiPSC-derived GRN-deficient astrocytes delay spiking activity of developing neurons.

Frontotemporal dementia (FTD) refers to a group of neurodegenerative disorders that are characterized by pathology predominantly localized to the frontal and temporal lobes. Approximately 40% of FTD cases are familial, and up to 20% of these are caused by heterozygous loss of function mutations in the gene encoding for progranulin (PGRN), GRN. The mechanisms by which loss of PGRN leads to FTD remain incompletely understood.

3D bioprinting complex models of cancer.

Cancer is characterized by the uncontrolled division of cells, resulting in the formation of tumors. The tumor microenvironment (TME) consists of a variety of cell types present within a heterogeneous extracellular matrix (ECM). Current 2D culture methods for mimicking this microenvironment remain limited due to spatial constraints.

Optimization of precision nanofiber micelleplexes for DNA delivery.

As nucleic acid (NA) technologies continue to revolutionize medicine, new delivery vehicles are needed to effectively transport NA cargoes into cells. Uniform and length-tunable nanofiber micelleplexes have recently shown promise as versatile polymeric delivery vehicles for plasmid DNA, however the effects of several key parameters on micelleplex transfection and stability remain unknown. In this work, we compare poly(fluorenetrimethylenecarbonate)--poly(2-(dimethylamino)ethyl methacrylate) (PFTMC--PDMAEMA) nanofiber micelleplexes to nanosphere micelleplexes and PDMAEMA polyplexes, examining the effects of complexation buffer, the temporal and serum stability of nanofiber micelleplexes, as well as the effects of cell density, cell type, and polymer DP upon transfection efficiency and cell viability.

Differentiation of Peritubular Myoid-Like Cells from Human Induced Pluripotent Stem Cells.

Infertility affects 10-15% of couples, with half attributed to male factors. An improved understanding of the cell-type-specific dysfunction contributing to male infertility is needed to improve available therapies; however, human testicular tissues are difficult to obtain for research purposes. To overcome this, researchers have begun to use human induced pluripotent stem cells (hiPSCs) to generate various testis-specific cell types in vitro.

Testing specificity and sensitivity of wastewater-based epidemiology for detecting SARS-CoV-2 in four communities on Vancouver Island, Canada.

We report wastewater surveillance of the spread of SARS-CoV-2 based upon 24-h composite influent samples taken weekly from four wastewater treatment plants (WWTP) on Vancouver Island, BC, Canada between January 3, 2021 and July 10, 2021. Samples were analyzed by reverse transcription quantitative polymerase chain reaction targeting the N1 and N2 gene fragments of SARS-CoV-2 and a region of the replication associate protein of the pepper mottle mosaic virus (PMMoV) serving as endemic control. Only a small proportion of samples had quantifiable levels of N1 or N2.

Length-Controlled Nanofiber Micelleplexes as Efficient Nucleic Acid Delivery Vehicles.

Micelleplexes show great promise as effective polymeric delivery systems for nucleic acids. Although studies have shown that spherical micelleplexes can exhibit superior cellular transfection to polyplexes, to date there has been no report on the effects of micelleplex morphology on cellular transfection. In this work, we prepared precision, length-tunable poly(fluorenetrimethylenecarbonate)--poly(2-(dimethylamino)ethyl methacrylate) (PFTMC--PDMAEMA) nanofiber micelleplexes and compared their properties and transfection activity to those of the equivalent nanosphere micelleplexes and polyplexes.

Using clinically derived human tissue to 3-dimensionally bioprint personalized testicular tubules for in vitro culturing: first report.

Objective: To study the feasibility and spermatogenic potential of 3-dimensional (3D) bioprinting personalized human testicular cells derived from a patient with nonobstructive azoospermia (NOA).

Design: A human testicular biopsy from a single donor with NOA was dissociated into single cells, expanded in vitro, and 3D bioprinted into tubular structures akin to the seminiferous tubule using AGC-10 bioink and an RX1 bioprinter with a CENTRA coaxial microfluidic printhead from Aspect Biosystems. Three-dimensional organoid cultures were used as a nonbioprinted in vitro control.

Protocol for printing 3D neural tissues using the BIO X equipped with a pneumatic printhead.

3D bioprinting-a type of additive manufacturing-can create 3D tissue constructs resembling tissues. Here, we present a protocol for 3D printing neural tissues using Axolotl Biosciences' fibrin-based bioink and the CELLINK BIO X bioprinter with a pneumatic printhead. This workflow can be applied to printing 3D tissue models using a variety of cell lines and any chemically crosslinked bioink.

Trends in hydrogel-based encapsulation technologies for advanced cell therapies applied to limb ischemia.

Ischemia occurs when blood flow is reduced or restricted, leading to a lack of oxygen and nutrient supply and removal of metabolites in a body part. Critical limb ischemia (CLI) is a severe clinical manifestation of peripheral arterial disease. Atherosclerosis serves as the main cause of CLI, which arises from the deposition of lipids in the artery wall, forming atheroma and causing inflammation.

Smart Bioinks for the Printing of Human Tissue Models.

3D bioprinting has tremendous potential to revolutionize the field of regenerative medicine by automating the process of tissue engineering. A significant number of new and advanced bioprinting technologies have been developed in recent years, enabling the generation of increasingly accurate models of human tissues both in the healthy and diseased state. Accordingly, this technology has generated a demand for smart bioinks that can enable the rapid and efficient generation of human bioprinted tissues that accurately recapitulate the properties of the same tissue found in vivo.

Drug-releasing Microspheres for Stem Cell Differentiation.

The ability of stem cells to differentiate into specialized cells make them a valuable tool for therapeutic applications. 3D bioprinting, a subset of additive manufacturing, uses bioinks composed of cells and biomaterials to create living tissues. The use of bioactive factors like small molecules and proteins can promote stem cell differentiation into the desired cell phenotypes for tissue regeneration.