Long Bai, Zhidao Xia, James T. Triffitt, Jiacan Su

2024, 5(1): 1–2. doi:https://doi.org/10.12336/biomatertransl.2024.01.001

Lei Qi, Tong Zhao, Jinge Yan, Weiwen Ge, Weidong Jiang, Jing Wang, Mazaher Gholipourmalekabadi, Kaili Lin, Xiuhui Wang, Lei Zhang

2024, 5(1): 3–20. doi:https://doi.org/10.12336/biomatertransl.2024.01.002

Reconstruction of bone defects or fractures caused by ageing, trauma and tumour resection is still a great challenge in clinical treatment. Although autologous bone graft is considered as gold standard, the source of natural bone is limited. In recent years, regenerative therapy based on bioactive materials has been proposed for bone reconstruction. Specially, numerous studies have indicated that bioactive ceramics including silicate and phosphate bioceramics exhibit excellent osteoinductivity and osteoconductivity, further promote bone regeneration. In addition, magnesium (Mg) element, as an indispensable mineral element, plays a vital role in promoting bone mineralisation and formation. In this review, different types of Mg-containing bioceramics including Mg-containing calcium phosphate-based bioceramics (such as Mg-hydroxyapatite, Mg-biphasic calcium phosphate). Mg-containing calcium silicate-based bioceramics (such as Mg₂SiO₄, Ca₂MgSi₂O₇ and Mg-doped bioglass), Mg-based biocements, Mg-containing metal/polymer-bioceramic composites were systematacially summarised. Additionally, the fabrication technologies and their materiobiological effects were deeply discussed, Clinical applications and perspectives of magnesium-containing bioceramics for bone repair are highlighted. Overall, Mg-containing bioceramics are regarded as regenerative therapy with their optimised performance. Furthermore, more in-depth two-way researches on their performance and structure are essential to satisfy their clinical needs.

Zhangjie Li, Dingyuan Yu, Chenyang Zhou, Feifan Wang, Kangyi Lu, Yijun Liu, Jiaqi Xu, Lian Xuan, Xiaolin Wang

2024, 5(1): 21–32. doi:https://doi.org/10.12336/biomatertransl.2024.01.003

In recent years, advances in microfabrication technology and tissue engineering have propelled the development of a novel drug screening and disease modelling platform known as organoid-on-a-chip. This platform integrates organoids and organ-on-a-chip technologies, emerging as a promising approach for in vitro modelling of human organ physiology. Organoid-on-a-chip devices leverage microfluidic systems to simulate the physiological microenvironment of specific organs, offering a more dynamic and flexible setting that can mimic a more comprehensive human biological context. However, the lack of functional vasculature has remained a significant challenge in this technology. Vascularisation is crucial for the long-term culture and in vitro modelling of organoids, holding important implications for drug development and personalised medical approaches. This review provides an overview of research progress in developing vascularised organoid-on-a-chip models, addressing methods for in vitro vascularisation and advancements in vascularised organoids. The aim is to serve as a reference for future endeavors in constructing fully functional vascularised organoid-on-a-chip platforms.

Haoyu Guo, Mingke Guo, Zhidao Xia, Zengwu Shao

2024, 5(1): 33–45. doi:https://doi.org/10.12336/biomatertransl.2024.01.004

Drug therapy towards tumours often causes adverse effects because of their non-specific nature. Membrane-coated technology and membrane-coated nanoparticles provide an advanced and promising platform of targeted and safe delivery. By camouflaging the nanoparticles with natural derived or artificially modified cell membranes, the nano-payloads are bestowed with properties from cell membranes such as longer circulation, tumour or inflammation-targeting, immune stimulation, augmenting the performance of traditional therapeutics. In this review, we review the development of membrane coating technology, and summarise the technical details, physicochemical properties, and research status of membrane-coated nanoparticles from different sources in tumour treatment. Finally, we also look forward to the prospects and challenges of transforming membrane coating technology from experiment into clinical use. Taken together, membrane-coated nanoparticles are bound to become one of the most potential anti-tumour strategies in the future.

Xiaoxiang Ren, Ruixue Xu, Chenjie Xu, Jiacan Su

2024, 5(1): 46–58. doi:https://doi.org/10.12336/biomatertransl.2024.01.005

Exosomes, nanoscopic extracellular vesicles produced by cells, are pivotal in mediating intracellular communication by transporting nucleic acids, proteins, lipids, and other bioactive molecules, thereby influencing physiological and pathological states. Their endogenous origin and inherent diversity confer distinct advantages over synthetic vehicles like liposomes and nanoparticles in diagnostic and therapeutic applications. Despite their potential, the clinical utility of exosomes is hampered by challenges such as limited storage stability, yield, purity, and targeting efficiency. This review focuses on exosomes as targeted therapeutic agents, examining their biogenesis, classification, isolation, and characterisation, while also addressing the current limitations in yield, purity, and targeting. We delve into the literature to propose optimisation strategies that can enhance their therapeutic efficacy and accelerate the translation of exosome-based therapies into clinical practice.

Huaxin Yang, Mengjia Zheng, Yuyue Zhang, Chaochang Li, Joseph Ho Chi Lai, Qizheng Zhang, Kannie WY Chan, Hao Wang, Xin Zhao, Zijiang Yang, Chenjie Xu

2024, 5(1): 59–68. doi:https://doi.org/10.12336/biomatertransl.2024.01.006

A composite scaffold composed of a porous scaffold and hydrogel filling can facilitate engraftment, survival, and retention in cell transplantation processes. This study presents a composite scaffold made of poly(ε-caprolactone) (PCL) and methacrylated hyaluronic acid (MeHA) hydrogel and describes the corresponding physical properties (surface area, porosity, and mechanical strength) and host response (angiogenesis and fibrosis) after subcutaneous transplantation. Specifically, we synthesise MeHA with different degrees of substitution and fabricate a PCL scaffold with different porosities. Subsequently, we construct a series of PCL/MeHA composite scaffolds by combining these hydrogels and scaffolds. In experiments with mice, the scaffold composed of 3% PCL and 10–100 kDa, degree of substitution 70% MeHA results in the least fibrosis and a higher degree of angiogenesis. This study highlights the potential of PCL/MeHA composite scaffolds for subcutaneous cell transplantation, given their desirable physical properties and host response.

Jin Yang, Kanwal Fatima, Xiaojun Zhou, Chuanglong He

2024, 5(1): 69–83. doi:https://doi.org/10.12336/biomatertransl.2024.01.007

The repair of large load-bearing bone defects requires superior mechanical strength,  a feat that a single hydrogel scaffold cannot achieve. The objective is to seamlessly  integrate optimal microarchitecture, mechanical robustness, vascularisation, and  osteoinductive biological responses to effectively address these critical load-bearing  bone defects. To confront this challenge, three-dimensional (3D) printing technology  was employed to prepare a polycaprolactone (PCL)-based integrated scaffold. Within  the voids of 3D printed PCL scaffold, a methacrylate gelatin (GelMA)/methacrylated  silk fibroin (SFMA) composite hydrogel incorporated with parathyroid hormone  (PTH) peptide-loaded mesoporous silica nanoparticles (PTH@MSNs) was embedded,  evolving into a porous PTH@MSNs/GelMA/SFMA/PCL (PM@GS/PCL) scaffold.  The feasibility of fabricating this functional scaffold with a customised hierarchical  structure was confirmed through meticulous chemical and physical characterisation.  Compression testing unveiled an impressive strength of 17.81 ± 0.83 MPa for the  composite scaffold. Additionally, in vitro angiogenesis potential of PM@GS/PCL  scaffold was evaluated through Transwell and tube formation assays using human  umbilical vein endothelium, revealing the superior cell migration and tube network  formation. The alizarin red and alkaline phosphatase staining assays using bone  marrow-derived mesenchymal stem cells clearly illustrated robust osteogenic  differentiation properties within this scaffold. Furthermore, the bone repair potential  of the scaffold was investigated on a rat femoral defect model using micro-computed  tomography and histological examination, demonstrating enhanced osteogenic and  angiogenic performance. This study presents a promising strategy for fabricating a  microenvironment-matched composite scaffold for bone tissue engineering, providing  a potential solution for effective bone defect repair.

Yan Xu, Fuxin Wei

2024, 5(1): 84–85. doi:https://doi.org/10.12336/biomatertransl.2024.01.008

Danli Cui, Yiting Lei

2024, 5(1): 86–88. doi:https://doi.org/10.12336/biomatertransl.2024.01.009

Kaibo Zhang, Weili Fu

2024, 5(1): 89–91. doi:https://doi.org/10.12336/biomatertransl.2024.01.010