A brief review on the mechanisms and approaches of silk spinning-inspired biofabrication

From molecular mechanisms to clinical translation: Silk fibroin-based biomaterials for next-generation wound healing

Silk fibroin (SF) is a natural polymeric material that has attracted intense research attention in the field of wound healing due to its exceptional mechanical properties, tunable biodegradability, and multifunctional bioactivity. This review systematically summarizes the preparation strategies, functional modifications, and multidimensional application mechanisms of SF and its composite materials in wound healing. The innovative applications of SF in intelligent dressing design, immunometabolic regulation, controlled drug release, stem-cell function modulation, and bioelectrical-activity-mediated microenvironment remodeling is further explored, while analyzing the therapeutic efficacy and cost-effectiveness of SF through clinical translation cases. Distinct from previous reviews, this work not only integrates the latest advances in SF molecular mechanisms and material design but also emphasizes its potential in precision medicine, such as the development of genetically engineered SF for customized immunoregulatory networks. Finally, the article highlights the current challenges in the development of SF materials, including mechanical stability, degradation controllability, and standardization of large-scale production, and envisions future research directions driven by 3D bioprinting and synthetic biology technologies. This review provides a theoretical foundation and technical reference information for the development of efficient, multifunctional, and clinically translatable SF-based materials for application in wound healing.

Reviewing Additive Manufacturing Techniques: Material Trends and Weight Optimization Possibilities Through Innovative Printing Patterns

Additive manufacturing is transforming modern industries by enabling the production of lightweight, complex structures while minimizing material waste and energy consumption. This review explores its evolution, covering historical developments, key technologies, and emerging trends. It highlights advancements in material innovations, including metals, polymers, composites, and ceramics, tailored to enhance mechanical properties and expand functional applications. Special emphasis is given to bioinspired designs and their contribution to enhancing structural efficiency. Additionally, the potential of these techniques for sustainable manufacturing and industrial scalability is discussed. The findings contribute to a broader understanding of Additive Manufacturing's impact on design optimization and material performance, offering insights into future research and industrial applications.

Modifying Naturally Occurring, Nonmammalian-Sourced Biopolymers for Biomedical Applications

Natural biopolymers have a rich history, with many uses across the fields of healthcare and medicine, including formulations for wound dressings, surgical implants, tissue culture substrates, and drug delivery vehicles. Yet, synthetic-based materials have been more successful in translation due to precise control and regulation achievable during manufacturing. However, there is a renewed interest in natural biopolymers, which offer a diverse landscape of architecture, sustainable sourcing, functional groups, and properties that synthetic counterparts cannot fully replicate as processing and sourcing of these materials has improved. Proteins and polysaccharides derived from various sources (crustaceans, plants, insects, etc.) are highlighted in this review. We discuss the common types of polysaccharide and protein biopolymers used in healthcare and medicine, highlighting methods and strategies to alter structures and intra- and interchain interactions to engineer specific functions, products, or materials. We focus on biopolymers obtained from natural, nonmammalian sources, including silk fibroins, alginates, chitosans, chitins, mucins, keratins, and resilins, while discussing strategies to improve upon their innate properties and sourcing standardization to expand their clinical uses and relevance. Emphasis will be placed on methods that preserve the structural integrity and native biological functions of the biopolymers and their makers. We will conclude by discussing the untapped potential of new technologies to manipulate native biopolymers while controlling their secondary and tertiary structures, offering a perspective on advancing biopolymer utility in novel applications within biomedical engineering, advanced manufacturing, and tissue engineering.

Design considerations and biomaterials selection in embedded extrusion 3D bioprinting

In embedded extrusion 3D bioprinting, a temporary matrix preserves a paste-like filament ejecting from a narrow nozzle. For granular sacrificial matrices, the methodology is known as the freeform reversible embedding of suspended hydrogels (FRESH). Embedded extrusion 3D bioprinting methods result in more rapid and controlled manufacturing of cell-laden tissue constructs, particularly vascular and multi-component structures. This report focuses on the working principles and bioink design criteria for implementing conventional embedded extrusion and FRESH 3D bioprinting strategies. We also present a set of experimental data as a guideline for selecting the support bath or matrix. We discuss the advantages of embedded extrusion methods over conventional biomanufacturing methods. This work provides a short recipe for selecting inks and printing parameters for desired shapes in embedded extrusion and FRESH 3D bioprinting methods.

Disentangling the Web: An Interdisciplinary Review on the Potential and Feasibility of Spider Silk Bioproduction

The remarkable material properties of spider silk, such as its high toughness and tensile strength combined with its low density, make it a highly sought-after material with myriad applications. In addition, the biological nature of spider silk makes it a promising, potentially sustainable alternative to many toxic or petrochemical-derived materials. Therefore, interest in the heterologous production of spider silk proteins has greatly increased over the past few decades, making recombinant spider silk an important frontier in biomanufacturing. This has resulted in a diversity of potential host organisms, a large space for sequence design, and a variety of downstream processing techniques and product applications for spider silk production. Here, we highlight advances in each of these technical aspects as well as white spaces therein, still ripe for further investigation and discovery. Additionally, industry landscaping, patent analyses, and interviews with Key Opinion Leaders help define both the research and industry landscapes. In particular, we found that though textiles dominated the early products proposed by companies, the versatile nature of spider silk has opened up possibilities in other industries, such as high-performance materials in automotive applications or biomedical therapies. While continuing enthusiasm has imbued scientists and investors alike, many technical and business considerations still remain unsolved before spider silk can be democratized as a high-performance product. We provide insights and strategies for overcoming these initial hurdles, and we highlight the importance of collaboration between academia, industry, and policy makers. Linking technical considerations to business and market entry strategies highlights the importance of a holistic approach for the effective scale-up and commercial viability of spider silk bioproduction.

A comprehensive gene expression analysis of the unique three-layered cocoon of the cecropia moth, Hyalophora cecropia

The larvae of the moth Hyalophora cecropia spin silk cocoons with morphologically distinct layers. We investigated the expression of the individual silk protein components of these cocoons in relation to the morphology of the silk gland and its affiliation to the different layers of the cocoon. The study used transcriptomic and proteomic analyses to identify 91 proteins associated with the silk cocoons, 63 of which have a signal peptide indicating their secretory nature. We checked the specificity of their expression in different parts of the SG and the presence of the corresponding protein products in each cocoon layer. Differences were observed among less abundant proteins with unclear functions. The representation of proteins in the inner envelope and intermediate space was similar, except for a higher proportion of probable contaminating proteins, mostly originating from the gut. On the other hand, the outer envelope contains a number of putative enzymes with unclear function. However, the protein most specific to the outer layer has sequence homology to putative serine/threonine kinase-like proteins and some adhesive proteins, and its closest homolog in Bombyx mori was found in the scaffold silk. This research provides valuable insights into the silk production of the cecropia moth, highlighting both similarities and differences to other moth species.

Regenerated Fiber's Ideal Target: Comparable to Natural Fiber

The toughness of silk naturally obtained from spiders and silkworms exceeds that of all other natural and man-made fibers. These insects transform aqueous protein feedstocks into mechanically specialized materials, which represents an engineering phenomenon that has developed over millions of years of natural evolution. Silkworms have become a new research hotspot due to the difficulties in collecting spider silk and other challenges. According to continuous research on the natural spinning process of the silkworm, it is possible to divide the main aspects of bionic spinning into two main segments: the solvent and behavior. This work focuses on the various methods currently used for the spinning of artificial silk fibers to replicate natural silk fibers, providing new insights based on changes in the fiber properties and production processes over time.