The current study introduces two novel, smart polymer three-dimensional (3D)-printable interpenetrating polymer network (IPN) hydrogel biomaterials with favorable chemical, mechanical, and morphological properties for potential applications in traumatic brain injury (TBI) such as potentially assisting in the restoration of neurological function through closure of the wound deficit and neural tissue regeneration. Additionally, removal of injury matter to allow for the appropriate scaffold grafting may assist in providing a TBI treatment. Furthermore, due to the 3D printability of the IPN biomaterials, complex structures can be designed and fabricated to mimic the native shape and structure of the injury sight, which can…
Many drugs show promising results in laboratory research but eventually fail clinical trials. We hypothesize that one main reason for this translational gap is that current cancer models are inadequate. Most models lack the tumor-stroma interactions, which are essential for proper representation of cancer complexed biology. Therefore, we recapitulated the tumor heterogenic microenvironment by creating fibrin glioblastoma bioink consisting of patient-derived glioblastoma cells, astrocytes, and microglia. In addition, perfusable blood vessels were created using a sacrificial bioink coated with brain pericytes and endothelial cells. We observed similar growth curves, drug response, and genetic signature of glioblastoma cells grown in our…
Osteocytes, essential regulators of bone homeostasis, are embedded in the mineralized bone matrix. Given the spatial arrangement of osteocytes, bioprinting represents an ideal method to biofabricate a 3D osteocyte network with a suitable surrounding matrix similar to native bone tissue. Here, we reported a 3D bioprinted osteocyte-laden hydrogel for biomimetic mineralization in vitro with exceptional shape fidelity, a high cell density (107 cells per ml) and high cell viability (85–90%). The bioinks were composed of biomimetic modified biopolymers, namely, gelatine methacrylamide (GelMA) and hyaluronic acid methacrylate (HAMA), with or without type I collagen. The osteocyte-laden constructs were printed and cultured…
3D printing provides a novel approach to repair bone defects using customized biomimetic tissue scaffolds. To make a bone substitute closest to natural bone structure and composition, two different types of hydroxyapatite, Nano hydroxyapatite (nHA) and deproteinized bovine bone (DBB), were dispersed into collagen (CoL) to prepare the bio-ink for 3D printing. In doing so, a porous architecture was manufactured with 3D printing technology. The physical and chemical properties of the materials were evaluated, including biocompatibility and effect on the osteogenic differentiation of the human bone marrow-derived mesenchyme stem cells (hBMSCs). The XPS, XRD, FTIR, and the mechanical analysis of…
Three-dimensional bioprinting is an emerging technology for fabricating living 3D constructs, and it has shown great promise in tissue engineering. Bioinks are scaffold materials mixed with cells used by 3D bioprinting to form a required cell-laden structure. In this paper, a novel bioink made of gelatin methacrylamide (GelMA) and collagen (Col) doped with tyrosinase (Ty) is presented for the 3D bioprinting of living skin tissues. Ty has the dual function of being an essential bioactive compound in the skin regeneration process and also as an enzyme to facilitate the crosslink of Col and GelMA. Further, enzyme crosslinking together with photocrosslinking…
This paper presents a new way to obtain collagen/hydroxyapatite (COLL/HA) composite materials by 3D printing. Because of high tendency of segregation of COLL/HA composite materials, printing was done using COLL/Ca2+ gel (even COLL/Ca(OH)2) followed by precipitation of HA and crosslinking of COLL. The HA precipitation occurs simultaneously with crosslinking of COLL molecules, these processes being assured by the presence of glutaraldehyde supplemented PBS solution. By printing with COLL/Ca2+ at acidic pH homogeneity was increased. FTIR spectroscopy and microscopy reveal HA formation as the main inorganic phase these nanoparticles being homogeneously dispersed in the volume. In vitro biocompatibility assays were performed…
The aim of this study was to investigate the osteogenic effect of three different cell-seeded 3D-bioplotted scaffolds in a ovine calvarial critical-size defect model. The choice of scaffold-materials was based on their applicability for 3D-bioplotting and respective possibility to produce tailor-made scaffolds for the use in cranio-facial surgery for the replacement of complex shaped boneparts. Scaffold raw-materials are known to be osteoinductive when being cell-seeded [poly(L-lactide-co-glycolide) (PLGA)] or having components with osteoinductive properties as tricalciumphosphate (TCP) or collagen (Col) or chitosan. The scaffold-materials PLGA, TCP/Col, and HYDR (TCP/Col/chitosan) were cell-seeded with osteoblast-like cells whether gained from bone (OLB) or from…
For tissue engineering, scaffolds should be biocompatible and promote neovascularization. Because little is known on those specific properties, we herein studied in vivo the host angiogenic and inflammatory response after implantation of commonly used scaffold materials. Porous poly(l-lactide-co-glycolide) (PLGA) and collagen–chitosan–hydroxyapatite hydrogel scaffolds were implanted into dorsal skinfold chambers of balb/c mice. Additional animals received cortical bone as an isogeneic, biological implant, while chambers of animals without implants served as controls. Angiogenesis and neovascularization as well as leukocyte–endothelial cell interaction and microvascular permeability were analyzed over 14 day using intravital fluorescence microscopy. PLGA scaffolds showed a slight increase in leukocyte…
In Tissue Engineering and bone reconstruction, alongside the choice of materials, the scaffold design is of great importance. Three dimensional structures not only permit the tuning of chemical and mechanical properties, but they can also copy the outer form of the required bone or cartilaginous structures. While new processes that create such 3D scaffolds by means of Rapid Prototyping have been developed, they are still restricted to a limited type of materials. At the Freiburger Materialforschungszentrum, our group has developed a new process called 3D BioplottingTM. Most kinds of polymers and biopolymers can be used for the fabrication of 3D…