Tissue Engineering. Part B, Reviews最新文献

In the 21st century, significant progress has been made in repairing damaged materials through material engineering. However, the creation of large-scale artificial materials still faces a major challenge in achieving proper vascularization. To address this issue, researchers have turned to biomaterials and three-dimensional (3D) bioprinting techniques, which allow for the combination of multiple biomaterials with improved mechanical and biological properties that mimic natural materials. Hydrogels, known for their ability to support living cells and biological components, have played a crucial role in this research. Among the recent developments, 3D bioprinting has emerged as a promising tool for constructing hybrid scaffolds. However, there are several challenges in the field of bioprinting, including the need for nanoscale biomimicry, the formulation of hydrogel blends, and the ongoing complexity of vascularizing biomaterials, which requires further research. On a positive note, 3D bioprinting offers a solution to the vascularization problem due to its precise spatial control, scalability, and reproducibility compared with traditional fabrication methods. This paper aims at examining the recent advancements in 3D bioprinting technology for creating blood vessels, vasculature, and vascularized materials. It provides a comprehensive overview of the progress made and discusses the limitations and challenges faced in current 3D bioprinting of vascularized tissues. In addition, the paper highlights the future research directions focusing on the development of 3D bioprinting techniques and bioinks for creating functional materials.

Tissue engineering, a crucial approach in medical research and clinical applications, aims to regenerate damaged organs. By combining stem cells, biochemical factors, and biomaterials, it encounters challenges in designing complex 3D structures. Artificial intelligence (AI) enhances tissue engineering through computational modeling, biomaterial design, cell culture optimization, and personalized medicine. This review explores AI applications in organ tissue engineering (bone, heart, nerve, skin, cartilage), employing various machine learning (ML) algorithms for data analysis, prediction, and optimization. Each section discusses common ML algorithms and specific applications, emphasizing the potential and challenges in advancing regenerative therapies.

The repair of nasal septal cartilage is a key challenge in cosmetic and functional surgery of the nose, as it determines its shape and its respiratory function. Supporting the dorsum of the nose is essential for both the prevention of nasal obstruction and the restoration of the nose structure. Most surgical procedures to repair or modify the nasal septum focus on restoring the external aspect of the nose by placing a graft under the skin, without considering respiratory concerns. Tissue engineering offers a more satisfactory approach, in which both the structural and biological roles of the nose are restored. To achieve this goal, nasal cartilage engineering research has led to the development of scaffolds capable of accommodating cartilaginous extracellular matrix-producing cells, possessing mechanical properties close to those of the nasal septum, and retaining their structure after implantation in vivo. The combination of a non-resorbable core structure with suitable mechanical properties and a biocompatible hydrogel loaded with autologous chondrocytes or mesenchymal stem cells is a promising strategy. However, the stability and immunotolerance of these implants are crucial parameters to be monitored over the long term after in vivo implantation, to definitively assess the success of nasal cartilage tissue engineering. Here, we review the tissue engineering methods to repair nasal cartilage, focusing on the type and mechanical characteristics of the biomaterials; cell and implantation strategy; and the outcome with regard to cartilage repair.

The main focus of this article is the role of lipids in biomineralization. Much of the discussion on biomineralization focuses on proteins in these decades. Indeed, collagen and acidic noncollagenous proteins effectively serve as templates for mineralization. However, other macromolecules such as lipids and polysaccharides have received less attention despite their abundance at mineralization sites. The matrix vesicle (MV) theory is widely accepted as the induction of early mineralization. Although ion concentration within the vesicles has been discussed in the initial mineralization in this theory, the role of phospholipids that constitute the vesicle membrane has not been discussed much. Comprehensive considerations, including pathological mineralization, exist regardless of the localization of MVs, the involvement of bacteria in dental calculus formation, and biomineralization caused by marine organisms such as corals, suggesting that initial mineralization found in these biological conditions might be a common reaction relating to lipids. In contrast, despite the abundance of lipids, mineralization occurs only in the limited tissue within our body. In other words, gathering knowledge and creating a path to understanding about lipid-based mineralization is extremely important in proposing new bone disease treatment methods. This article describes how lipids influence nucleation, mineralization, and expansion during hard tissue formation.

The healing process after tendon injury is often accompanied by the formation of peritendinous adhesion, contributing to limb dysfunction and exerting detrimental effects on the individuals, as well as the development of society and economy. With the continuous development of material science, as well as the augmented understanding of tendon healing and the mechanism of peritendinous adhesion formation, materials used for the fabrication of barrier membranes against peritendinous adhesion emerge endlessly. In this article, based on the analysis of the mechanism of adhesion formation, we first review the commonly used natural and synthetic materials, along with their corresponding fabrication strategies, in order to furnish valuable insights for the future optimization and development of antiperitendinous adhesion barrier membranes. This article also discusses the interaction between antiadhesion materials and cells for ameliorating peritendinous adhesion.

Regenerative medicine aims to restore the function of diseased or damaged tissues and organs by cell therapy, gene therapy, and tissue engineering, along with the adjunctive application of bioactive molecules. Traditional bioactive molecules, such as growth factors and cytokines, have shown great potential in the regulation of cellular and tissue behavior, but have the disadvantages of limited source, high cost, short half-life, and side effects. In recent years, herbal compounds extracted from natural plants/herbs have gained increasing attention. This is not only because herbal compounds are easily obtained, inexpensive, mostly safe, and reliable, but also owing to their excellent effects, including anti-inflammatory, antibacterial, antioxidative, proangiogenic behavior and ability to promote stem cell differentiation. Such effects also play important roles in the processes related to tissue regeneration. Furthermore, the moieties of the herbal compounds can form physical or chemical bonds with the scaffolds, which contributes to improved mechanical strength and stability of the scaffolds. Thus, the incorporation of herbal compounds as bioactive molecules in biomaterials is a promising direction for future regenerative medicine applications. Herein, an overview on the use of bioactive herbal compounds combined with different biomaterial scaffolds for regenerative medicine application is presented. We first introduce the classification, structures, and properties of different herbal bioactive components and then provide a comprehensive survey on the use of bioactive herbal compounds to engineer scaffolds for tissue repair/regeneration of skin, cartilage, bone, neural, and heart tissues. Finally, we highlight the challenges and prospects for the future development of herbal scaffolds toward clinical translation. Overall, it is believed that the combination of bioactive herbal compounds with biomaterials could be a promising perspective for the next generation of regenerative medicine.