Singh Yogendra Pratap, Moses Joseph Christakiran, Bhunia Bibhas K, Nandi Samit Kumar, Mandal Biman B
Biomaterial and Tissue Engineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati - 781039, Assam, India.
J Mater Chem B. 2018 Sep 28;6(36):5671-5688. doi: 10.1039/c8tb01344f. Epub 2018 Jun 25.
The osteochondral healthcare market is driven by the increasing demand for affordable and biomimetic scaffolds. To meet this demand, silk fibroin (SF) from Bombyx mori and Antheraea assamensis is used to fabricate a biphasic scaffold, with fiber-free and fiber-reinforced phases, stimulating cartilage and bone revival. The fabrication is a facile reproducible process using single polymer (SF), for both phases, designed in a continuous and integrated manner. Physicochemical and mechanical scaffold characterization, display interconnected pores with differential swelling and tunable degradation. The compressive modulus values, extend to 40 kPa and 25%, for tensile strain, at elongation. The scaffold support, for growth and proliferation of chondrocytes and osteoblasts, for respective cartilage and bone regeneration, is verified from in vitro assessment. Up-regulation of alkaline phosphatase (ALP) activity, extracellular matrix secretion and gene expression are significant; with acceptable in vitro immune response. Upon implantation in rabbit osteochondral defects for 8 weeks, the histological and micro-CT examinations show biphasic scaffolds significantly enhance regeneration of cartilage and subchondral bone tissues, as compared to monophasic scaffolds. The regenerated bone mineral density (BMD) ranges from 600-700 mg hydroxyapatite (HA) per cm. The results, therefore, showcase the critically positive characteristics of in vitro ECM deposition, and in vivo regeneration of osteochondral tissue by this hierarchically structured biphasic scaffold.
骨软骨医疗保健市场受到对经济实惠且仿生支架需求不断增加的推动。为满足这一需求，来自家蚕和柞蚕的丝素蛋白（SF）被用于制造一种双相支架，该支架具有无纤维和纤维增强相，可刺激软骨和骨再生。制造过程是一个使用单一聚合物（SF）的简便可重复过程，两个阶段均以连续和集成的方式设计。对支架进行物理化学和力学表征，结果显示其具有相互连通的孔隙，且具有不同的膨胀性和可调节的降解性。压缩模量值在伸长时可达40 kPa，拉伸应变为25%。通过体外评估验证了该支架对软骨细胞和成骨细胞的生长和增殖具有支持作用，可分别用于软骨和骨再生。碱性磷酸酶（ALP）活性、细胞外基质分泌和基因表达的上调显著，且体外免疫反应可接受。在兔骨软骨缺损处植入8周后，组织学和微型计算机断层扫描（micro-CT）检查显示，与单相支架相比，双相支架显著增强了软骨和软骨下骨组织的再生。再生骨矿物质密度（BMD）范围为每立方厘米600 - 700毫克羟基磷灰石（HA）。因此，这些结果展示了这种分层结构的双相支架在体外细胞外基质沉积以及骨软骨组织体内再生方面的极其积极的特性。
