Reconstruction of osteochondral(OC)defects represents an immense challenge due to the need for synchronous regeneration of special stratified tissues.The revolutionary innovation of bioprinting provides a robust metho...Reconstruction of osteochondral(OC)defects represents an immense challenge due to the need for synchronous regeneration of special stratified tissues.The revolutionary innovation of bioprinting provides a robust method for precise fabrication of tissue-engineered OCs with hierarchical structure;however,their spatial living cues for simultaneous fulfilment of osteogenesis and chondrogenesis to reconstruct the cartilage-bone interface of OC are underappreciated.Here,inspired by natural OC bilayer features,anisotropic bicellular living hydrogels(ABLHs)simultaneously embedding articular cartilage progenitor cells(ACPCs)and bone mesenchymal stem cells(BMSCs)in stratified layers were precisely fabricated via two-channel extrusion bioprinting.The optimum formulation of the 7%GelMA/3%AlgMA hydrogel bioink was demonstrated,with excellent printability at room temperature and maintained high cell viability.Moreover,the chondrogenic ability of ACPCs and the osteogenic ability of BMSCs were demonstrated in vitro,confirming the inherent differential spatial regulation of ABLHs.展开更多
Sphingosine-1-phosphate receptor 1 （S1PR1）, a G protein-coupled recep （GPCR）. controls vasct stability by stabilizing vascular endothelial （VE）-cadherin junctional localization and inhibiting vascular endothelia...Sphingosine-1-phosphate receptor 1 （S1PR1）, a G protein-coupled recep （GPCR）. controls vasct stability by stabilizing vascular endothelial （VE）-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2（VEGFR2） signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown.In this study,we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS,acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions. The endothelial cell -spectific deletion of Gαs in mice causes early embryonic lethality with massive hemorrhage and a disorganized Vaseuiature.The immunostaining results revealed that Gαs deletion remarkably reduces the junctional localization of VE-cadherin, whereas the mull cell coverage of the vessels is not impaired.In addition, we found-that Gαs depletion blocks the S1PR1-activation induced VE-cadherin stabilization at junctons,supporting that Gαs acts downstream of S1PR1 signaling ThuS, our results demonstrate that Gαs is an essential mediator to relay S1PR1 signaling and maintain vascular integrity.展开更多
基金This work was supported by grants from the National Key R&D Program of China(Grant Nos.2018YFA0703100 and 2022YFC2502902)the National Nature Science Foundation of China(Grant Nos.82072442,82272494,82072082,32122046,32101102)+3 种基金the Orthopaedic Medical Innovation Center of Jiangsu(CXZX202209)Key Laboratory of Orthopaedics of Suzhou(SZS2022017)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Shenzhen Fundamental Research Foundation(Grant Nos.JSGG20210629144537007,JCYJ20210324115814040,and JCYJ20210324113001005).
文摘Reconstruction of osteochondral(OC)defects represents an immense challenge due to the need for synchronous regeneration of special stratified tissues.The revolutionary innovation of bioprinting provides a robust method for precise fabrication of tissue-engineered OCs with hierarchical structure;however,their spatial living cues for simultaneous fulfilment of osteogenesis and chondrogenesis to reconstruct the cartilage-bone interface of OC are underappreciated.Here,inspired by natural OC bilayer features,anisotropic bicellular living hydrogels(ABLHs)simultaneously embedding articular cartilage progenitor cells(ACPCs)and bone mesenchymal stem cells(BMSCs)in stratified layers were precisely fabricated via two-channel extrusion bioprinting.The optimum formulation of the 7%GelMA/3%AlgMA hydrogel bioink was demonstrated,with excellent printability at room temperature and maintained high cell viability.Moreover,the chondrogenic ability of ACPCs and the osteogenic ability of BMSCs were demonstrated in vitro,confirming the inherent differential spatial regulation of ABLHs.
基金partially supported by the grants from the Ministry of Science & Technology-China (Nos.2014CB964600 and 2012CB966800)the National Science Foundation of China (Nos. 31301125 and 31071283)+2 种基金Shenzhen Peacock Plan (No. KQCX20130628112914292)Shenzhen Key Laboratory for Molecular Biology of Neural Development (No. ZDSY20120617112838879)SIAT Innovation Program for Excellent Young Researchers (No. 201404)
文摘Sphingosine-1-phosphate receptor 1 （S1PR1）, a G protein-coupled recep （GPCR）. controls vasct stability by stabilizing vascular endothelial （VE）-cadherin junctional localization and inhibiting vascular endothelial growth factor receptor 2（VEGFR2） signaling. However, the molecular mechanisms that link S1PR1 signaling to intracellular effectors remain unknown.In this study,we demonstrate that the heterotrimeric G protein subfamily member Gαs, encoded by GNAS,acts as a relay mediator of S1PR1 signaling to control vascular integrity by stabilizing VE-cadherin at endothelial junctions. The endothelial cell -spectific deletion of Gαs in mice causes early embryonic lethality with massive hemorrhage and a disorganized Vaseuiature.The immunostaining results revealed that Gαs deletion remarkably reduces the junctional localization of VE-cadherin, whereas the mull cell coverage of the vessels is not impaired.In addition, we found-that Gαs depletion blocks the S1PR1-activation induced VE-cadherin stabilization at junctons,supporting that Gαs acts downstream of S1PR1 signaling ThuS, our results demonstrate that Gαs is an essential mediator to relay S1PR1 signaling and maintain vascular integrity.
