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There is a need for the development of effective treatments for focal articular cartilage injuries. We previously developed a multiphasic 3D-bioplotted osteochondral scaffold design that can drive site-specific tissue formation when seeded with adipose-derived stem cells (ASC). The objective of this study was to evaluate this scaffold in a large animal model. Osteochondral defects were generated in the trochlear groove of Yucatan minipigs and repaired with scaffolds that either contained or lacked an electrospun tidemark and were either unseeded or seeded with ASC. Implants were monitored via computed tomography (CT) over the course of 4 months of in vivo implantation and compared to both open lesions and autologous explants. ICRS II evaluation indicated that defects with ASC-seeded scaffolds had healing that most closely resembled the aulogous explant. Scaffold-facilitated subchondral bone repair mimicked the structure of native bone tissue, but cartilage matrix staining was not apparent within the scaffold. The open lesions had the highest volumetric infill detected using CT analysis (p

Osteoarthritis is a degenerative joint disease that limits mobility of the affected joint due to the degradation of articular cartilage and subchondral bone. The limited regenerative capacity of cartilage presents significant challenges when attempting to repair or reverse the effects of cartilage degradation. Tissue engineered medical products are a promising alternative to treat osteochondral degeneration due to their potential to integrate into the patient's existing tissue. The goal of this study was to create a scaffold that would induce site-specific osteogenic and chondrogenic differentiation of human adipose-derived stem cells (hASC) to generate a full osteochondral implant. Scaffolds were fabricated using 3D-bioplotting of biodegradable polycraprolactone (PCL) with either β-tricalcium phosphate (TCP) or decellularized bovine cartilage extracellular matrix (dECM) to drive site-specific hASC osteogenesis and chondrogenesis, respectively. PCL-dECM scaffolds demonstrated elevated matrix deposition and organization in scaffolds seeded with hASC as well as a reduction in collagen I gene expression. 3D-bioplotted PCL scaffolds with 20% TCP demonstrated elevated calcium deposition, endogenous alkaline phosphatase activity, and osteopontin gene expression. Osteochondral scaffolds comprised of hASC-seeded 3D-bioplotted PCL-TCP, electrospun PCL, and 3D-bioplotted PCL-dECM phases were evaluated and demonstrated site-specific osteochondral tissue characteristics. This technique holds great promise as cartilage morbidity is minimized since autologous cartilage harvest is not required, tissue rejection is minimized via use of an abundant and accessible source of autologous stem cells, and biofabrication techniques allow for a precise, customizable methodology to rapidly produce the scaffold.

Plant-based proteins are promoted as nutritious, environmentally safe, and a key element for food security. Numerous studies using environmental life cycle assessments confirmed plant-based meat alternatives are more environmentally favorable than animal-derived meat. However, most missed other factors from protein extraction and concentration that contribute to environmental impact (both positive and negative). Furthermore, few studies examined the entire environmental impact because they overlooked social and nutritional life cycle assessments. Many publications assumed most environmental impact occurred in crop cultivation before high protein products are manufactured. However, industrial plant-based protein extraction, concentration, and purification require large amounts of natural resources, energy, chemicals, and highly specialized equipment seldom accurately assessed from an environmental, social, and nutritional perspective. This paper presents opinions and perspectives on additional information to consider to fully realize environmental benefits of highly proteinaceous plant-based food ingredients. Elements are also discussed we perceive as "hot spots" for future assessments in presenting a complete picture for minimizing environmental impact and how the numerous actors in this supply chain can transform our food system and secure protein availability for future generations. [ABSTRACT FROM AUTHOR]

Recapitulation of multiscale structure–function properties of cells, cell‐secreted extracellular matrix, and 3D architecture of natural tissues is central to engineering biomimetic tissue substitutes. Toward achieving biomimicry, a variety of biofabrication processes have been developed, which can be broadly classified into five categories—fiber and fabric formation, additive manufacturing, surface modification, remote fields, and other notable processes—each with specific advantages and limitations. The majority of biofabrication literature has focused on using a single process at a time, which often limits the range of tissues that could be created with relevant features that span nano to macro scales. With multiscale biomimicry as the goal, development of hybrid biofabrication strategies that synergistically unite two or more processes to complement each other's strengths and limitations has been steadily increasing. This work discusses recent literature in this domain and attempts to equip the reader with the understanding of selecting appropriate processes that can harmonize toward creating engineered tissues with appropriate multiscale structure–function properties. Opportunities related to various hybridization schemes and a future outlook on scale‐up biofabrication have also been discussed. This article is categorized under:Nanotechnology Approaches to Biology > Nanoscale Systems in BiologyImplantable Materials and Surgical Technologies > Nanotechnology in Tissue Repair and Replacement [ABSTRACT FROM AUTHOR]

Purpose: Musculoskeletal soft tissues possess highly aligned extracellular collagenous networks that provide structure and strength. Such an organization dictates tissue-specific mechanical properties but can be difficult to replicate by engineered biological substitutes. Nanofibrous electrospun scaffolds have demonstrated the ability to control cell-secreted collagen alignment, but concerns exist regarding their scalability for larger and anatomically relevant applications. Additive manufacturing processes, such as melt extrusion-based 3D-Bioplotting, allow fabrication of structurally relevant scaffolds featuring highly controllable porous microarchitectures. Materials and Methods: In this study, we investigate the effects of 3D-bioplotted scaffold design on the compressive elastic modulus of neotissue formed in vivo in a subcutaneous rat model and its correlation with the alignment of ECM collagen fibers. Polycaprolactone scaffolds featuring either 100 or 400 µm interstrand spacing were implanted for 4 or 12 weeks, harvested, cryosectioned, and characterized using atomic-force-microscopy-based force mapping. Results: The compressive elastic modulus of the neotissue formed within the 100 µm design was significantly higher at 4 weeks (p < 0.05), but no differences were observed at 12 weeks. In general, the tissue stiffness was within the same order of magnitude and range of values measured in native musculoskeletal soft tissues including the porcine meniscus and anterior cruciate ligament. Finally, a significant positive correlation was noted between tissue stiffness and the degree of ECM collagen fiber alignment (p < 0.05) resulting from contact guidance provided by scaffold strands. Conclusion: These findings demonstrate the significant effects of 3D-bioplotted scaffold microarchitectures in the organization and sub-tissue-level mechanical properties of ECM in vivo. [ABSTRACT FROM AUTHOR]