Articular cartilage(AC)is an avascular and flexible connective tissue located on the bone surface in the diarthrodial joints.AC defects are common in the knees of young and physically active individuals.Because of the...Articular cartilage(AC)is an avascular and flexible connective tissue located on the bone surface in the diarthrodial joints.AC defects are common in the knees of young and physically active individuals.Because of the lack of suitable tissue-engineered artificial matrices,current therapies for AC defects,espe-cially full-thickness AC defects and osteochondral interfaces,fail to replace or regenerate damaged carti-lage adequately.With rapid research and development advancements in AC tissue engineering(ACTE),functionalized hydrogels have emerged as promising cartilage matrix substitutes because of their favor-able biomechanical properties,water content,swelling ability,cytocompatibility,biodegradability,and lubricating behaviors.They can be rationally designed and conveniently tuned to simulate the extracel-lular matrix of cartilage.This article briefly introduces the composition,structure,and function of AC and its defects,followed by a comprehensive review of the exquisite(bio)design and(bio)fabrication of func-tionalized hydrogels for AC repair.Finally,we summarize the challenges encountered in functionalized hydrogel-based strategies for ACTE both in vivo and in vitro and the future directions for clinical translation.展开更多
Neutrophils play a pivotal role in orchestrating the immune system response to biomaterials,the onset and resolution of chronic inflammation,and macrophage polarization.However,the neutrophil response to biomaterials ...Neutrophils play a pivotal role in orchestrating the immune system response to biomaterials,the onset and resolution of chronic inflammation,and macrophage polarization.However,the neutrophil response to biomaterials and the consequent impact on tissue engineering approaches is still scarcely understood.Here,we report an in vitro culture model that comprehensively describes the most important neutrophil functions in the light of tissue repair.We isolated human primary neutrophils from peripheral blood and exposed them to a panel of hard,soft,naturally-and synthetically-derived materials.The overall trend showed increased neutrophil survival on naturally derived constructs,together with higher oxidative burst,decreased myeloperoxidase and neutrophil elastase and decreased cytokine secretion compared to neutrophils on synthetic materials.The culture model is a step to better understand the immune modulation elicited by biomaterials.Further studies are needed to correlate the neutrophil response to tissue healing and to elucidate the mechanism triggering the cell response and their consequences in determining inflammation onset and resolution.展开更多
基金supported by grants from the AO Foundation (AOOCD Consortium TA1711481)Areas of Excellence Scheme from the University Grant Council of Hong Kong (Ao E/M-402/20)+1 种基金Theme-based Research Scheme from the University Grant Council of Hong Kong (T13-402/17-N)Key-Area Research and Development Program of Guangdong Province (2019B010941001)
文摘Articular cartilage(AC)is an avascular and flexible connective tissue located on the bone surface in the diarthrodial joints.AC defects are common in the knees of young and physically active individuals.Because of the lack of suitable tissue-engineered artificial matrices,current therapies for AC defects,espe-cially full-thickness AC defects and osteochondral interfaces,fail to replace or regenerate damaged carti-lage adequately.With rapid research and development advancements in AC tissue engineering(ACTE),functionalized hydrogels have emerged as promising cartilage matrix substitutes because of their favor-able biomechanical properties,water content,swelling ability,cytocompatibility,biodegradability,and lubricating behaviors.They can be rationally designed and conveniently tuned to simulate the extracel-lular matrix of cartilage.This article briefly introduces the composition,structure,and function of AC and its defects,followed by a comprehensive review of the exquisite(bio)design and(bio)fabrication of func-tionalized hydrogels for AC repair.Finally,we summarize the challenges encountered in functionalized hydrogel-based strategies for ACTE both in vivo and in vitro and the future directions for clinical translation.
文摘Neutrophils play a pivotal role in orchestrating the immune system response to biomaterials,the onset and resolution of chronic inflammation,and macrophage polarization.However,the neutrophil response to biomaterials and the consequent impact on tissue engineering approaches is still scarcely understood.Here,we report an in vitro culture model that comprehensively describes the most important neutrophil functions in the light of tissue repair.We isolated human primary neutrophils from peripheral blood and exposed them to a panel of hard,soft,naturally-and synthetically-derived materials.The overall trend showed increased neutrophil survival on naturally derived constructs,together with higher oxidative burst,decreased myeloperoxidase and neutrophil elastase and decreased cytokine secretion compared to neutrophils on synthetic materials.The culture model is a step to better understand the immune modulation elicited by biomaterials.Further studies are needed to correlate the neutrophil response to tissue healing and to elucidate the mechanism triggering the cell response and their consequences in determining inflammation onset and resolution.