Construction of functional porous titanium scaffold is drawing ever growing attention, due to its effectiveness in solving the mechanical mismatch between titanium implant and bone tissue. However, the poor water permeability as well as the problem in achieving uniform surface modification inside scaffold hinders the further biomedical application of porous titanium scaffold. In this study, largescale functional Ti O2 nanostructures（nanonetwork, nanoplate and nanowire） were constructed on three-dimensional porous titanium scaffolds surface via an effective hydrothermal treatment method. These nanostructures increase the hydrophilicity of the titanium scaffold surface, facilitating the cell culture medium to penetrate into the inner pore of the scaffold. Zeta potential analyses indicate that the surface electrical properties depend on the nanostructure, with nanowire exhibiting the lowest potential at p H 7.4. The influence of the nano-functionalized scaffold on protein adsorption and cell adhesion was examined. The results indicate that the nano-functionalized surface could modulate protein adsorption and bone marrow derived mesenchymal stem cells（BMSCs） adhesion, with the nanowire functionalized porous scaffold homogeneously promoting protein adsorption and BMSCs adhesion. Our research will facilitate future research on the development of novel functional porous scaffold.
Lei QianPeng YuJinquan ZengZhifeng ShiQiyou WangGuoxin TanChengyun Ning
Inspired by the constitution of things in the natural world,three-dimensional (3D)nanofiber scaffold/cells complex was constructed via the combination of electrospinning technology and origami techniques.The nanofiber boxes prepared by origami provided a limited space for the layer-by-layer nanofiber films,and the human fetal osteoblasts (hFOBs)seeded on the both sides of the nanofiber films were expected to facilitate the bonding,of the adjacent nanofiber films through the secretion of extracellular matrix.Specifically,the hFOBs presented 3D distribution in the nanofiber scaffold,and they can stretch across the gaps between the adjacent nanofiber films,forming the cell layers and filling the whole 3D nanofiber scaffold.Eventually,a 3D block composed of electrospun nanofiber scaffold and cells was obtained',which possesses potential applications in bone tissue engineering.Interestingly,we also created 3D nanofiber structures that range from simple forms to intricate architectures via origami,indicating that the combination of electrospinning technology and origami techniques is a feasible method for the 3D construction of tissue engineering scaffolds.
Juqing SongGuanglin ZhuHuichang GaoLin WangNanying LiXuetao ShiYingjun Wang
Corneal disease is the main cause of blindness and keratoplasty is the only widely accepted treatment. Shortage of donor tissue makes the biomaterials for corneal regeneration a hot area of research. Collagen is the main component of corneal stroma, so collagen becomes a promising material for corneal repair. However, due to the drawbacks of collagen, it needs to be further modified to satisfy the requirement of corneal regeneration. In this article, we highlight the importance of collagen materials for corneal repair, and summarize several methods of preparing collagen based corneal regeneration materials, including chemical crosslinking, plastic compression of collagen, and collagen vitrigel. These modification methods can make collagen membranes with remarkable properties such as enough mechanical and suture retention strength, antibacterial property and excellent optical property. These materials may provide potential treatment for corneal disease.
The process of bone repair is highly regulated by a large number of bioactive factors.Thus,a“cocktail”of bioactive factors supplemented to the defect sites is desirable for bone repair.In this regard,small extracellular vesicles(sEVs)derived from mesenchymal stem cells hold great potential in tissue repair.Nevertheless,the poor homing and retention of sEVs greatly limited their possible clinical application.In the present work,DMPE-PEG-CREKA was inserted into the membrane of sEVs released from adipose-derived mesenchymal stem cells to obtain CREKA functionalized sEVs(CREKA-sEVs),which could target fibrin to accumulate and retain in bone defects.Our results showed that CREKA-sEVs,like sEVs,promoted the osteogenic differentiation of BMSCs,the angiogenic property of HUVECs,and modulated the polarization of macrophages in vitro.Furthermore,due to the improved fibrin-binding and retention capacity of CREKA-sEVs,they enhanced the bone repair substantially in the rat femoral defect model.This study provided a new strategy to improve the therapeutic efficiency of sEVs and showed that CREKA-sEVs had great application value in bone tissue repair.
Qi WuXiaoling FuXian LiJing LiWeiju HanYingjun Wang
In this paper, we fabricated three kinds of 3D microgrooves with different depth on biocompatible poly（lactic-co-glycolic acid） （PLGA） substrate via combination of soft-lithography and melt-casting methods, and investigated in detail their influence on C2C12 cell behaviors. It is found that cell proliferation, migration, alignment, spatial distribution, F-actin protein expression and gene expression are all remarkably distinct on these microgrooved samples and the smooth control PLGA substrate. The associated underlying mechanisms were further analyzed and discussed using real-time living cell monitoring, confocal laser scanning microscopy and gene microarray. Our preliminary results suggested that 3D microstruc- ture could affect cell behaviors in a much more extensive manner than what we had understood before.
In this research, polypyrrole nanocone arrays doped with β-Naphthalene sulphonic acid （PPy-NSA） were built. This film was expected to control protein adsorption and bacterial adhesion by potential-induced reversibly redox. The scanning Kelvin probe microscopy （SKPM） and surface contact angles （SCA） tests suggested that the surface potential and wettability of PPy-NSA nanocone arrays could be controlled by simply controlling its redox property via applying potential. The controllable surface potential and wettability in return controlled the adsorption of protein and adhesion of bacteria. The proposed material might find application in the preparation of smart biomaterial surfaces that can regulate proteins and bacterial adhesion by a simple potential switching.
Zhengnan ZhouWeiping LiTianrui HePeng YuGuoxin TanChengyun Ning
Oligo（ethylene glycol） （-OEG） and amino （-NH2） mixed self-assembled monolayers （SAMs） were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells （MSCs） and osteopontin （OPN） adsorption. We found that all surfaces presenting -NH2 groups favored cell responses regardless of the surface charge. Meanwhile, OPN adsorption could remain stable on the mixed SAMs over a certain range of charge densities. Our work provides some insights into cell responses and protein adsorption to surface charge.
Lijing HaoTianjie LiNaru ZhaoFuzhai CuiChang DuYingjun Wang
