Academic Unit Translational Medical Sciences, School of Medicine, University of Nottingham, UK.
Advanced Materials Research Group, Faculty of Engineering, University of Nottingham, UK; Physics Department, Faculty of Science, Mansoura University, Mansoura 35516, Egypt.
Carbohydr Polym. 2022 Apr 15;282:119126. doi: 10.1016/j.carbpol.2022.119126. Epub 2022 Jan 12.
An innovative approach was developed to engineer a multi-layered chitosan scaffold for osteochondral defect repair. A combination of freeze drying and porogen-leaching out methods produced a porous, bioresorbable scaffold with a distinct gradient of pore size (mean = 160-275 μm). Incorporation of 70 wt% nano-hydroxyapatite (nHA) provided additional strength to the bone-like layer. The scaffold showed instantaneous mechanical recovery under compressive loading and did not delaminate under tensile loading. The scaffold supported the attachment and proliferation of human mesenchymal stem cells (MSCs), with typical adherent cell morphology found on the bone layer compared to a rounded cell morphology on the chondrogenic layer. Osteogenic and chondrogenic differentiation of MSCs preferentially occurred in selected layers of the scaffold in vitro, driven by the distinct pore gradient and material composition. This scaffold is a suitable candidate for minimally invasive arthroscopic delivery in the clinic with potential to regenerate damaged cartilage and bone.
一种创新的方法被开发出来，用于构建用于骨软骨缺损修复的多层壳聚糖支架。冷冻干燥和致孔剂沥滤方法的结合产生了一种多孔、可生物吸收的支架，具有明显的孔径梯度（平均为 160-275μm）。掺入 70wt%纳米羟基磷灰石（nHA）为骨样层提供了额外的强度。支架在压缩载荷下表现出瞬时的机械恢复，在拉伸载荷下不会分层。支架支持人骨髓间充质干细胞（MSCs）的附着和增殖，与软骨形成层上的圆形细胞形态相比，在骨层上发现了典型的贴壁细胞形态。体外培养时，MSCs 的成骨和成软骨分化优先发生在支架的选定层中，这是由明显的孔梯度和材料组成驱动的。这种支架是一种适用于微创关节镜下临床应用的候选材料，具有再生受损软骨和骨的潜力。
