Pub Date : 2024-09-19DOI: 10.1101/2024.09.13.612676
Nitish Satya Sai Gedela, Sachin Salim, Ryan D Radawiec, Julianna Marie Richie, Cynthia A Chestek, Anne Draelos, Galit Pelled
The octopus simplified nervous system holds the potential to reveal principles of motor circuits and improve brain-machine interface devices through computational modeling with machine learning and statistical analysis. Here, an array of carbon electrodes providing single-unit electrophysiology recordings were implanted into the octopus anterior nerve cord. The number of spikes and arm movements in response to stimulation at different locations along the arm were recorded. We observed that the number of spikes occurring within the first 100ms after stimulation were predictive of the resultant movement response. Computational models showed that temporal electrophysiological features could be used to predict whether an arm movement occurred with 88.64% confidence, and if it was a lateral arm movement or a grasping motion with 75.45% confidence. Both supervised and unsupervised methods were applied to gain streaming measurements of octopus arm movements and how their motor circuitry produces rich movement types in real time. Deep learning models and unsupervised dimension reduction identified a consistent set of features that could be used to distinguish different types of arm movements. These models generated predictions for how to evoke a particular, complex movement in an orchestrated sequence for an individual motor circuit.
{"title":"Single unit electrophysiology recordings and computational modeling can predict octopus arm movement","authors":"Nitish Satya Sai Gedela, Sachin Salim, Ryan D Radawiec, Julianna Marie Richie, Cynthia A Chestek, Anne Draelos, Galit Pelled","doi":"10.1101/2024.09.13.612676","DOIUrl":"https://doi.org/10.1101/2024.09.13.612676","url":null,"abstract":"The octopus simplified nervous system holds the potential to reveal principles of motor circuits and improve brain-machine interface devices through computational modeling with machine learning and statistical analysis. Here, an array of carbon electrodes providing single-unit electrophysiology recordings were implanted into the octopus anterior nerve cord. The number of spikes and arm movements in response to stimulation at different locations along the arm were recorded. We observed that the number of spikes occurring within the first 100ms after stimulation were predictive of the resultant movement response. Computational models showed that temporal electrophysiological features could be used to predict whether an arm movement occurred with 88.64% confidence, and if it was a lateral arm movement or a grasping motion with 75.45% confidence. Both supervised and unsupervised methods were applied to gain streaming measurements of octopus arm movements and how their motor circuitry produces rich movement types in real time. Deep learning models and unsupervised dimension reduction identified a consistent set of features that could be used to distinguish different types of arm movements. These models generated predictions for how to evoke a particular, complex movement in an orchestrated sequence for an individual motor circuit.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1101/2024.09.17.613535
James C Pearce, Jennie Samantha Campbell, Joann L Prior, Richard W Titball, James G Wakefield
The larvae of the greater waxmoth, Galleria mellonella, are gaining prominence as a versatile non-mammalian in vivo model to study host-pathogen interactions. Their ability to be maintained at 37C, coupled with a broad susceptibility to human pathogens and a distinct melanisation response that serves as a visual indicator for larval health, positions Galleria as a powerful resource for infection research. Despite these advantages, the lack of genetic tools, such as those available for zebrafish and fruit flies, has hindered development of the full potential of Galleria as a model organism. In this study, we describe a robust methodology for generating transgenic Galleria using the PiggyBac transposon system and for precise gene knockouts via CRISPR/Cas9 technology. These advances significantly enhance the utility of Galleria in molecular research, opening the way to its widespread use as an inexpensive and ethically compatible animal model for infection biology and beyond.
{"title":"PiggyBac mediated transgenesis and CRISPR/Cas9 knockout in the greater waxmoth, Galleria mellonella","authors":"James C Pearce, Jennie Samantha Campbell, Joann L Prior, Richard W Titball, James G Wakefield","doi":"10.1101/2024.09.17.613535","DOIUrl":"https://doi.org/10.1101/2024.09.17.613535","url":null,"abstract":"The larvae of the greater waxmoth, Galleria mellonella, are gaining prominence as a versatile non-mammalian in vivo model to study host-pathogen interactions. Their ability to be maintained at 37C, coupled with a broad susceptibility to human pathogens and a distinct melanisation response that serves as a visual indicator for larval health, positions Galleria as a powerful resource for infection research. Despite these advantages, the lack of genetic tools, such as those available for zebrafish and fruit flies, has hindered development of the full potential of Galleria as a model organism. In this study, we describe a robust methodology for generating transgenic Galleria using the PiggyBac transposon system and for precise gene knockouts via CRISPR/Cas9 technology. These advances significantly enhance the utility of Galleria in molecular research, opening the way to its widespread use as an inexpensive and ethically compatible animal model for infection biology and beyond.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1101/2024.09.13.612742
Francesca Renzi, Giovanni Puppini, Giovanni Battista Luciani, Christian Vergara
Characterizing flow within the right heart (RH) is particularly challenging due to its complex geometries.However, gaining insight into RH fluid dynamics is of extreme diagnostic importance given the high prevalence of acquired and congenital heart diseases with impaired RH functionality. In this study, we present a comprehensive, patient-specific, image-based computational analysis of the hemodynamics of the RH in healthy and repaired-ToF (ToF) cases. From multi-series cine-MTRI, we reconstruct the geometry and motion of the patient's right atrium, ventricle, and pulmonary and tricuspid valves. For this purpose, we develop a novel and flexible reconstruction procedure that enables us, for the first time, to integrate fully patient-specific tricuspid valve dynamics into a computational model, enhancing the accuracy of our RH blood flow simulations. This work provides novel insight into the altered hemodynamics of repaired-ToF RH with severe pulmonary regurgitation and into the hemodynamics changes induced by the pulmonary valve replacement intervention. Modelling the whole RH enables us to understand the contribution of the superior and inferior vena cava inflows to the ventricular filling, as well as the impact of the impaired right atrial function on the ventricular diastole. We analyze the turbulent and transitional behaviour by including the Large-Eddies Simulation sigma model in our computational framework. This highlights how the contribution of the smallest scales in the dissipation of the turbulent energy changes among health and disease.
{"title":"Investigating the right heart hemodynamics in the Tetralogy of Fallot: a computational study","authors":"Francesca Renzi, Giovanni Puppini, Giovanni Battista Luciani, Christian Vergara","doi":"10.1101/2024.09.13.612742","DOIUrl":"https://doi.org/10.1101/2024.09.13.612742","url":null,"abstract":"Characterizing flow within the right heart (RH) is particularly challenging due to its complex geometries.\u0000However, gaining insight into RH fluid dynamics is of extreme diagnostic importance given the high prevalence of acquired and congenital heart diseases with impaired RH functionality. In this study, we present a comprehensive, patient-specific, image-based computational analysis of the hemodynamics of the RH in healthy and repaired-ToF (ToF) cases. From multi-series cine-MTRI, we reconstruct the geometry and motion of the patient's right atrium, ventricle, and pulmonary and tricuspid valves. For this purpose, we develop a novel and flexible reconstruction procedure that enables us, for the first time, to integrate fully patient-specific tricuspid valve dynamics into a computational model, enhancing the accuracy of our RH blood flow simulations. This work provides novel insight into the altered hemodynamics of repaired-ToF RH with severe pulmonary regurgitation and into the hemodynamics changes induced by the pulmonary valve replacement intervention. Modelling the whole RH enables us to understand the contribution of the superior and inferior vena cava inflows to the ventricular filling, as well as the impact of the impaired right atrial function on the ventricular diastole. We analyze the turbulent and transitional behaviour by including the Large-Eddies Simulation sigma model in our computational framework. This highlights how the contribution of the smallest scales in the dissipation of the turbulent energy changes among health and disease.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"54 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1101/2024.09.17.613528
James C Pearce, Amy Housden, Nicola J Senior, Olivia L Champion, Joann L Prior, Richard W Titball, James G Wakefield
A limitation to the non-vertebrate 3Rs model Galleria mellonella has been the lack of genetic toolkit. A common requirement for genetic tractability is a method to introduce exogenous material to the unicellular embryo, the most common of which is microinjection. This short article describes a detailed method for rearing Galleria mellonella to collect large amounts of staged embryos and to dechorionate and microinject embryos with limited mortality.
{"title":"A microinjection protocol for the greater waxworm moth, Galleria mellonella","authors":"James C Pearce, Amy Housden, Nicola J Senior, Olivia L Champion, Joann L Prior, Richard W Titball, James G Wakefield","doi":"10.1101/2024.09.17.613528","DOIUrl":"https://doi.org/10.1101/2024.09.17.613528","url":null,"abstract":"A limitation to the non-vertebrate 3Rs model Galleria mellonella has been the lack of genetic toolkit. A common requirement for genetic tractability is a method to introduce exogenous material to the unicellular embryo, the most common of which is microinjection. This short article describes a detailed method for rearing Galleria mellonella to collect large amounts of staged embryos and to dechorionate and microinject embryos with limited mortality.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255972","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1101/2024.09.17.613377
Dan Ilya Piraner, Mohamad H Abedi, Maria J Duran Gonzalez, Adam Chazin-Gray, Iowis Zhu, Pavithran T Ravindran, Thomas Schlichthaerle, Buwei Huang, David Lee, David Baker, Kole T Roybal
Despite recent advances in mammalian synthetic biology, there remains a lack of modular synthetic receptors that can robustly respond to soluble ligands and in turn activate cellular functions. Such receptors would have extensive clinical potential to regulate the activity of engineered therapeutic cells, but to date only receptors against cell surface targets have approached clinical translation. To address this gap, we developed a receptor based on SynNotch, called synthetic intramembrane proteolysis receptors (SNIPRs), that have the added ability to be activated by soluble ligands, both natural and synthetic, with remarkably low baseline activity and high fold activation. SNIPRs are able to access an endocytic, pH-dependent cleavage mechanism to achieve soluble ligand sensing, in addition to employing a canonical-like pathway for detecting surface-bound ligands. We demonstrate the therapeutic capabilities of the receptor platform by localizing the activity of CAR T-cells to solid tumors where soluble disease-associated factors are expressed, bypassing the major hurdle of on-target off-tumor toxicity in bystander organs. We further applied the SNIPR platform to engineer fully synthetic signaling networks between cells orthogonal to natural signaling pathways, expanding the scope of synthetic biology. Our design framework enables cellular communication and environmental interactions, extending the capabilities of synthetic cellular networking in clinical and research contexts.
尽管哺乳动物合成生物学取得了最新进展,但仍缺乏能对可溶性配体做出强有力反应并进而激活细胞功能的模块化合成受体。这种受体在调节工程治疗细胞的活性方面具有广泛的临床潜力,但迄今为止,只有针对细胞表面靶点的受体已接近临床转化。为了填补这一空白,我们开发了一种基于 SynNotch 的受体,称为合成膜内蛋白水解受体(SNIPRs),这种受体还能被天然和合成的可溶性配体激活,基线活性极低,激活倍数极高。SNIPRs 除了采用类似于典范的途径检测表面结合配体外,还能通过内吞、pH 依赖性裂解机制实现可溶性配体感应。我们通过将 CAR T 细胞的活性定位到表达可溶性疾病相关因子的实体瘤上,证明了该受体平台的治疗能力,从而绕过了旁观器官的靶向非肿瘤毒性这一主要障碍。我们进一步应用 SNIPR 平台,在细胞间设计出与自然信号通路正交的全合成信号网络,从而扩大了合成生物学的范围。我们的设计框架实现了细胞通信和环境互动,拓展了合成细胞网络在临床和研究方面的能力。
{"title":"Engineered Receptors for Soluble Cell-to-Cell Communication","authors":"Dan Ilya Piraner, Mohamad H Abedi, Maria J Duran Gonzalez, Adam Chazin-Gray, Iowis Zhu, Pavithran T Ravindran, Thomas Schlichthaerle, Buwei Huang, David Lee, David Baker, Kole T Roybal","doi":"10.1101/2024.09.17.613377","DOIUrl":"https://doi.org/10.1101/2024.09.17.613377","url":null,"abstract":"Despite recent advances in mammalian synthetic biology, there remains a lack of modular synthetic receptors that can robustly respond to soluble ligands and in turn activate cellular functions. Such receptors would have extensive clinical potential to regulate the activity of engineered therapeutic cells, but to date only receptors against cell surface targets have approached clinical translation. To address this gap, we developed a receptor based on SynNotch, called synthetic intramembrane proteolysis receptors (SNIPRs), that have the added ability to be activated by soluble ligands, both natural and synthetic, with remarkably low baseline activity and high fold activation. SNIPRs are able to access an endocytic, pH-dependent cleavage mechanism to achieve soluble ligand sensing, in addition to employing a canonical-like pathway for detecting surface-bound ligands. We demonstrate the therapeutic capabilities of the receptor platform by localizing the activity of CAR T-cells to solid tumors where soluble disease-associated factors are expressed, bypassing the major hurdle of on-target off-tumor toxicity in bystander organs. We further applied the SNIPR platform to engineer fully synthetic signaling networks between cells orthogonal to natural signaling pathways, expanding the scope of synthetic biology. Our design framework enables cellular communication and environmental interactions, extending the capabilities of synthetic cellular networking in clinical and research contexts.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-18DOI: 10.1101/2024.09.17.613503
Charlotte Cresens, Samet Aytekin, Behrad Shaghaghi, Lotte Gerrits, Ana Montero-Calle, Rodrigo Barderas, Paul Kouwer, Susana Rocha
The impact of mechanical cues on cell behavior is increasingly being recognized, rendering hydrogel platforms that mimic the extracellular matrix indispensable in in vitro cell biology research. Here, we present a step-by-step protocol for synthesis and rheological characterization of polyacrylamide (PAAm) hydrogels with varying stiffnesses, produced as large circular unattached gels customizable in shape and size. We outline methods for their use in cell culture and downstream applications involving secretome or cell analysis, and protein visualization by fluorescence microscopy.
{"title":"Synthesis and mechanical characterization of polyacrylamide (PAAm) hydrogels with different stiffnesses for large-batch cell culture applications","authors":"Charlotte Cresens, Samet Aytekin, Behrad Shaghaghi, Lotte Gerrits, Ana Montero-Calle, Rodrigo Barderas, Paul Kouwer, Susana Rocha","doi":"10.1101/2024.09.17.613503","DOIUrl":"https://doi.org/10.1101/2024.09.17.613503","url":null,"abstract":"The impact of mechanical cues on cell behavior is increasingly being recognized, rendering hydrogel platforms that mimic the extracellular matrix indispensable in in vitro cell biology research. Here, we present a step-by-step protocol for synthesis and rheological characterization of polyacrylamide (PAAm) hydrogels with varying stiffnesses, produced as large circular unattached gels customizable in shape and size. We outline methods for their use in cell culture and downstream applications involving secretome or cell analysis, and protein visualization by fluorescence microscopy.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"8 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255974","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-17DOI: 10.1101/2024.09.12.612702
Fengting Ji, Mohammad R. Islam, Frederick Sebastian, Hannah Schilpp, Bingrui Wang, Yi Hua, Rouzbeh Amini, Ian A Sigal
Because of the crucial role of collagen fibers on soft tissue mechanics, there is great interest in techniques to incorporate them in computational models. Recently we introduced a direct fiber modeling approach for sclera based on representing the long interwoven fibers. Our method differs from the conventional continuum approach to modeling sclera that homogenizes the fibers and describes them as statistical distributions for each element. At large scale our method captured gross collagen fiber bundle architecture from histology and experimental intraocular pressure-induced deformations. At small scale, a direct fiber model of a sclera sample reproduced equi-biaxial experimental behavior from the literature. In this study our goal was a much more challenging task for the direct fiber modeling: to capture specimen-specific 3D fiber architecture and anisotropic mechanics of four sclera samples tested under equibiaxial and four non-equibiaxial loadings. Samples of sclera from three eyes were isolated and tested in five biaxial loadings following an approach previously reported. Using microstructural architecture from polarized light microscopy we then created specimen-specific direct fiber models. Model fiber orientations agreed well with the histological information (adjusted R2's>0.89). Through an inverse-fitting process we determined model characteristics, including specimen-specific fiber mechanical properties to match equibiaxial loading. Interestingly, the equibiaxial properties also reproduced all the non-equibiaxial behaviors. These results indicate that the direct fiber modeling method naturally accounted for tissue anisotropy within its fiber structure. Direct fiber modeling is therefore a promising approach to understand how macroscopic behavior arises from microstructure.
{"title":"Capturing sclera anisotropy using direct collagen fiber models. Linking microstructure to macroscopic mechanical properties.","authors":"Fengting Ji, Mohammad R. Islam, Frederick Sebastian, Hannah Schilpp, Bingrui Wang, Yi Hua, Rouzbeh Amini, Ian A Sigal","doi":"10.1101/2024.09.12.612702","DOIUrl":"https://doi.org/10.1101/2024.09.12.612702","url":null,"abstract":"Because of the crucial role of collagen fibers on soft tissue mechanics, there is great interest in techniques to incorporate them in computational models. Recently we introduced a direct fiber modeling approach for sclera based on representing the long interwoven fibers. Our method differs from the conventional continuum approach to modeling sclera that homogenizes the fibers and describes them as statistical distributions for each element. At large scale our method captured gross collagen fiber bundle architecture from histology and experimental intraocular pressure-induced deformations. At small scale, a direct fiber model of a sclera sample reproduced equi-biaxial experimental behavior from the literature. In this study our goal was a much more challenging task for the direct fiber modeling: to capture specimen-specific 3D fiber architecture and anisotropic mechanics of four sclera samples tested under equibiaxial and four non-equibiaxial loadings. Samples of sclera from three eyes were isolated and tested in five biaxial loadings following an approach previously reported. Using microstructural architecture from polarized light microscopy we then created specimen-specific direct fiber models. Model fiber orientations agreed well with the histological information (adjusted R2's>0.89). Through an inverse-fitting process we determined model characteristics, including specimen-specific fiber mechanical properties to match equibiaxial loading. Interestingly, the equibiaxial properties also reproduced all the non-equibiaxial behaviors. These results indicate that the direct fiber modeling method naturally accounted for tissue anisotropy within its fiber structure. Direct fiber modeling is therefore a promising approach to understand how macroscopic behavior arises from microstructure.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"16 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255975","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-17DOI: 10.1101/2024.09.12.612723
Se-Hwan Lee, Zizhao Li, Ellen Y Zhang, Dong Hwa Kim, Ziqi Huang, Sang Jin Lee, Hyun-Wook Kang, Jason A Burdick, Robert L Mauck, Su Chin Heo
Meniscus injuries present significant therapeutic challenges due to their limited self-healing capacity and diverse biological and mechanical properties across meniscal tissue. Conventional repair strategies neglect to replicate the complex zonal characteristics within the meniscus, resulting in suboptimal outcomes. In this study, we introduce an innovative, age- and stiffness-tunable meniscus decellularized extracellular matrix (DEM)-based hydrogel system designed for precision repair of heterogeneous, zonal-dependent meniscus injuries. By synthesizing age-dependent DEM hydrogels, we identified distinct cellular responses: fetal bovine meniscus-derived DEM promoted chondrogenic differentiation, while adult meniscus-derived DEM supported fibrochondrogenic phenotypes. The incorporation of methacrylate hyaluronic acid (MeHA) further refined the mechanical properties and injectability of the DEM-based hydrogels. The combination of age-dependent DEM with MeHA allowed for precise stiffness tuning, influencing cell differentiation and closely mimicking native tissue environments. In vivo tests confirmed the biocompatibility of hydrogels and their integration with native meniscus tissues. Furthermore, advanced 3D bioprinting techniques enabled the fabrication of hybrid hydrogels with biomaterial and mechanical gradients, effectively emulating the zonal properties of meniscus tissue and enhancing cell integration. This study represents a significant advancement in meniscus tissue engineering, providing a promising platform for customized regenerative therapies across a range of heterogeneous fibrous connective tissues.
半月板损伤的自愈能力有限,且半月板组织的生物和机械特性各不相同,这给治疗带来了巨大挑战。传统的修复策略忽视了复制半月板内复杂的分区特征,导致效果不理想。在本研究中,我们介绍了一种创新的、可调节年龄和硬度的半月板脱细胞细胞外基质(DEM)水凝胶系统,该系统设计用于精确修复异质性、分区依赖性半月板损伤。通过合成与年龄相关的 DEM 水凝胶,我们发现了不同的细胞反应:胎牛半月板衍生的 DEM 可促进软骨分化,而成人半月板衍生的 DEM 则支持纤维软骨表型。甲基丙烯酸透明质酸(MeHA)的加入进一步改善了基于 DEM 的水凝胶的机械性能和可注射性。与年龄相关的 DEM 与 MeHA 的结合可实现精确的硬度调整,影响细胞分化并密切模拟原生组织环境。体内测试证实了水凝胶的生物相容性及其与原生半月板组织的结合。此外,先进的三维生物打印技术还能制造出具有生物材料和机械梯度的混合水凝胶,从而有效模拟半月板组织的带状特性并增强细胞整合。这项研究代表了半月板组织工程学的重大进展,为各种异质纤维结缔组织的定制再生疗法提供了一个前景广阔的平台。
{"title":"Precision Repair of Zone-Specific Meniscal Injuries Using a Tunable Extracellular Matrix-Based Hydrogel System","authors":"Se-Hwan Lee, Zizhao Li, Ellen Y Zhang, Dong Hwa Kim, Ziqi Huang, Sang Jin Lee, Hyun-Wook Kang, Jason A Burdick, Robert L Mauck, Su Chin Heo","doi":"10.1101/2024.09.12.612723","DOIUrl":"https://doi.org/10.1101/2024.09.12.612723","url":null,"abstract":"Meniscus injuries present significant therapeutic challenges due to their limited self-healing capacity and diverse biological and mechanical properties across meniscal tissue. Conventional repair strategies neglect to replicate the complex zonal characteristics within the meniscus, resulting in suboptimal outcomes. In this study, we introduce an innovative, age- and stiffness-tunable meniscus decellularized extracellular matrix (DEM)-based hydrogel system designed for precision repair of heterogeneous, zonal-dependent meniscus injuries. By synthesizing age-dependent DEM hydrogels, we identified distinct cellular responses: fetal bovine meniscus-derived DEM promoted chondrogenic differentiation, while adult meniscus-derived DEM supported fibrochondrogenic phenotypes. The incorporation of methacrylate hyaluronic acid (MeHA) further refined the mechanical properties and injectability of the DEM-based hydrogels. The combination of age-dependent DEM with MeHA allowed for precise stiffness tuning, influencing cell differentiation and closely mimicking native tissue environments. In vivo tests confirmed the biocompatibility of hydrogels and their integration with native meniscus tissues. Furthermore, advanced 3D bioprinting techniques enabled the fabrication of hybrid hydrogels with biomaterial and mechanical gradients, effectively emulating the zonal properties of meniscus tissue and enhancing cell integration. This study represents a significant advancement in meniscus tissue engineering, providing a promising platform for customized regenerative therapies across a range of heterogeneous fibrous connective tissues.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"75 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1101/2024.09.11.612534
Lucia G. Brunel, Chris M. Long, Fotis Christakopoulos, Betty Cai, Patrik K. Johansson, Diya Singhal, Annika Enejder, David Myung, Sarah C Heilshorn
Hydrogels composed of collagen, the most abundant protein in the human body, are widely used as scaffolds for tissue engineering due to their ability to support cellular activity. However, collagen hydrogels with encapsulated cells often experience bulk contraction due to cell-generated forces, and conventional strategies to mitigate this undesired deformation often compromise either the fibrillar microstructure or cytocompatibility of the collagen. To support the spreading of encapsulated cells while preserving the structural integrity of the gels, we present an interpenetrating network (IPN) of two distinct collagen networks with different crosslinking mechanisms and microstructures. First, a physically self-assembled collagen network preserves the fibrillar microstructure and enables the spreading of encapsulated human corneal mesenchymal stromal cells. Second, an amorphous collagen network covalently crosslinked with bioorthogonal chemistry fills the voids between fibrils and stabilizes the gel against cell-induced contraction. This collagen IPN balances the biofunctionality of natural collagen with the stability of covalently crosslinked, engineered polymers. Taken together, these data represent a new avenue for maintaining both the fiber-induced spreading of cells and the structural integrity of collagen hydrogels by leveraging an IPN of fibrillar and amorphous collagen networks.
{"title":"Interpenetrating networks of fibrillar and amorphous collagen promote cell spreading and hydrogel stability","authors":"Lucia G. Brunel, Chris M. Long, Fotis Christakopoulos, Betty Cai, Patrik K. Johansson, Diya Singhal, Annika Enejder, David Myung, Sarah C Heilshorn","doi":"10.1101/2024.09.11.612534","DOIUrl":"https://doi.org/10.1101/2024.09.11.612534","url":null,"abstract":"Hydrogels composed of collagen, the most abundant protein in the human body, are widely used as scaffolds for tissue engineering due to their ability to support cellular activity. However, collagen hydrogels with encapsulated cells often experience bulk contraction due to cell-generated forces, and conventional strategies to mitigate this undesired deformation often compromise either the fibrillar microstructure or cytocompatibility of the collagen. To support the spreading of encapsulated cells while preserving the structural integrity of the gels, we present an interpenetrating network (IPN) of two distinct collagen networks with different crosslinking mechanisms and microstructures. First, a physically self-assembled collagen network preserves the fibrillar microstructure and enables the spreading of encapsulated human corneal mesenchymal stromal cells. Second, an amorphous collagen network covalently crosslinked with bioorthogonal chemistry fills the voids between fibrils and stabilizes the gel against cell-induced contraction. This collagen IPN balances the biofunctionality of natural collagen with the stability of covalently crosslinked, engineered polymers. Taken together, these data represent a new avenue for maintaining both the fiber-induced spreading of cells and the structural integrity of collagen hydrogels by leveraging an IPN of fibrillar and amorphous collagen networks.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-09-16DOI: 10.1101/2024.09.12.612768
Johane H. Bracamonte, Lionel Watkins, Betty Pat, Louis J. Dell'Italia, Jeffrey J. Saucerman, Jeffrey W. Holmes
Primary mitral regurgitation (MR) is a pathology that alters mechanical loading on the left ventricle and induces a distinctive ventricular remodeling response known as eccentric hypertrophy. Drug therapies may alleviate symptoms, but only mitral valve repair can provide significant recovery of cardiac function and dimensions. However, 20% of patients still develop systolic dysfunction post-operatively despite being treated according to the current guidelines. Thus, better understanding of the hypertrophic process in the setting of ventricular volume overload (VO) is needed to improve and better personalize the management of MR. To address this knowledge gap, we employ a Bayesian approach to combine data from 70 studies on experimental volume overload in dogs and rats and use it to calibrate a logic-based network model of hypertrophic signaling in myocytes. The calibrated model suggests that growth in experimental VO is mostly driven by the neurohormonal response, with an initial increase in myocardial tissue stretch being compensated by subsequent remodeling fairly early in the time course of VO. This observation contrasts with a common perception that volume-overload hypertrophy is driven primarily by increased myocyte strain. The model suggests that Endothelin1 receptor activity plays a central role in driving hypertrophic responses and the activation of the fetal gene program. The model reproduces a number of responses to drug therapy not used in its calibration, and predicts that a combination of endothelin receptor antagonist and angiotensin receptor blockers would have the greatest potential to dampen cardiomyocyte hypertrophy and dysfunction in VO.
{"title":"Contributions of mechanical loading and hormonal changes to eccentric hypertrophy during volume overload: a Bayesian analysis using logic-based network models.","authors":"Johane H. Bracamonte, Lionel Watkins, Betty Pat, Louis J. Dell'Italia, Jeffrey J. Saucerman, Jeffrey W. Holmes","doi":"10.1101/2024.09.12.612768","DOIUrl":"https://doi.org/10.1101/2024.09.12.612768","url":null,"abstract":"Primary mitral regurgitation (MR) is a pathology that alters mechanical loading on the left ventricle and induces a distinctive ventricular remodeling response known as eccentric hypertrophy. Drug therapies may alleviate symptoms, but only mitral valve repair can provide significant recovery of cardiac function and dimensions. However, 20% of patients still develop systolic dysfunction post-operatively despite being treated according to the current guidelines. Thus, better understanding of the hypertrophic process in the setting of ventricular volume overload (VO) is needed to improve and better personalize the management of MR. To address this knowledge gap, we employ a Bayesian approach to combine data from 70 studies on experimental volume overload in dogs and rats and use it to calibrate a logic-based network model of hypertrophic signaling in myocytes. The calibrated model suggests that growth in experimental VO is mostly driven by the neurohormonal response, with an initial increase in myocardial tissue stretch being compensated by subsequent remodeling fairly early in the time course of VO. This observation contrasts with a common perception that volume-overload hypertrophy is driven primarily by increased myocyte strain. The model suggests that Endothelin1 receptor activity plays a central role in driving hypertrophic responses and the activation of the fetal gene program. The model reproduces a number of responses to drug therapy not used in its calibration, and predicts that a combination of endothelin receptor antagonist and angiotensin receptor blockers would have the greatest potential to dampen cardiomyocyte hypertrophy and dysfunction in VO.","PeriodicalId":501308,"journal":{"name":"bioRxiv - Bioengineering","volume":"202 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142255979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}