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A growing body of evidence suggests that the sensory information from the cytoskeleton and integrins may be responsible for guiding migration during mechano- and haptotaxis. However, the dual function of these subcellular structures as mechano-sensors and -actuators is only partially understood. Using a new cell chamber described in the preceding companion paper (Ref to part I, Raeber et al. 2007a) we investigated the migration response of adhesion-dependent fibroblasts embedded 3-dimensionally within synthetic protease-sensitive poly(ethylene glycol) hydrogels to stepwise and cyclic mechanical loads. To that end, we developed a spatially and temporally resolved migration analysis technique capable of providing estimates of statistical cell migration parameters along and perpendicular to the main strain direction. Fibroblasts reoriented themselves in the direction of principal strain, increased their proteolytic migration activity and moved preferentially parallel to the principal strain axis. These results point to a possible correlation between planes of iso-strain and migration direction. 相似文献
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Raja Vadivelu Navid Kashaninejad Mohammad Reza Nikmaneshi Rubina Rahaman Khadim Seyedeh Sarah Salehi Naveen Chintala Ramulu Yasuyuki Sakai Masaki Nishikawa Bahar Firoozabadi Nam-Trung Nguyen 《Advanced Biosystems》2021,5(2):2000108
Digital microfluidics based on liquid marble (LM) has recently emerged as a promising platform for liquid handling and cell-based assays. However, evaporation is a critical problem in such platforms, hindering their wide-range applications in various fields. This study aims to develop a functional sessile LM system for long-term 3D cell culture. Previously, this study group and others demonstrated that floating LM-based bioreactors could reduce the evaporation rate, and were thus suitable for growing multicellular spheroids. However, floating LMs are not robust and easily collapse. Herein, an evaporation-reducing sessile LM by embedding LM with agarose gel is proposed. Through a series of comprehensive mathematical modeling, numerical simulations, and experimental investigations (both with and without biological cells), it is shown that such a platform acts as a moisture absorption system to control the evaporation and thus extends the life span of LMs. It is also found that unlike pure LMs, the LMs filled with agarose maintain their spherical shapes within 72 h inside a humidified incubator. Moreover, the presence of agarose significantly contributes to minimizing evaporation and improves the viability of the harvested multicellular spheroids. These results can open up a new avenue in using LMs in life sciences and chemistry. 相似文献
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目的 利用透明质酸建立小鼠胎肝细胞3D培养体系。 方法 分离获得胚胎12-14天胎肝细胞,利用KM培养基进行初步2D肝干/祖细胞的筛选培养,并利用透明质酸及KM培养基配制水凝胶建立3D细胞培养体系。 结果 胎肝细胞在2D体系中呈现克隆状生长。分离培养获得的肝干/祖细胞克隆在透明质酸建立的3D培养体系保持增殖活性,并进一步获得肝细胞功能特性,表现为3D培养上清中白蛋白合成和尿素水平显著增加。Q-PCR结果显示随着3D培养时间的延长,其肝细胞干性标志如AFP、CK19、EpCAM、Prox1等表达水平都大幅度降低且接近成年小鼠肝脏表达水平。 结论 本研究成功建立基于透明质酸的小鼠胎肝细胞的3D无血清培养体系,并可促进小鼠胎肝细胞肝细胞功能进一步成熟。 相似文献
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Duncan Davis‐Hall Vy Nguyen Tyler J. D'Ovidio Ethan Tsai Ganna Bilousova Chelsea M. Magin 《Advanced Biosystems》2019,3(10)
The extracellular matrix (ECM) controls keratinocyte proliferation, migration, and differentiation through β‐integrin signaling. Wound‐healing research requires expanding cells in vitro while maintaining replicative capacity; however, early terminal differentiation under traditional culture conditions limits expansion. Here, a design of experiments approach identifies poly(ethylene glycol)‐based hydrogel formulations with mechanical properties (elastic modulus, E = 20.9 ± 0.56 kPa) and bioactive peptide sequences that mimic the epidermal ECM. These hydrogels enable systematic investigation of the influence of cell‐binding domains from fibronectin (RGDS), laminin (YIGSR), and collagen IV (HepIII) on keratinocyte stemness and β1 integrin expression. Quantification of 14‐day keratin protein expression shows four hydrogels improve stemness compared to standard techniques. Three hydrogels increase β1 integrin expression, demonstrating a positive linear relationship between stemness and β1 integrin expression. Multifactorial statistical analysis predicts an optimal peptide combination ([RGDS] = 0.67 mm , [YIGSR] = 0.13 mm , and [HepIII] = 0.02 mm ) for maintaining stemness in vitro. Best‐performing hydrogels exhibit no decrease in Ki‐67‐positive cells compared to standards (15% decrease, day 7 to 14; p < 0.05, Tukey Test). These data demonstrate that precisely designed hydrogel biomaterials direct integrin expression and promote proliferation, improving the regenerative capability of cultured keratinocytes for basic science and translational work. 相似文献
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脱氧核糖核酸(Deoxyribonucleic acid,DNA)不仅可作为生物遗传的物质基础,又以其可编程性、功能多样性、生物相容性和生物可降解性等优点,在生物材料的构建方面表现出巨大的潜力。DNA水凝胶是一种主要由DNA参与形成的三维网状聚合物材料,同时因其保留的DNA生物性能与自身骨架的机械性能的完美融合使得它成为近年来最受关注的新兴功能高分子材料之一。目前,基于各种功能核酸序列或通过结合不同的功能材料制备的单组分或多组分DNA水凝胶,已广泛用于生物医学、分子检测及环境保护的研究或应用领域中。文中主要总结了近十几年来DNA水凝胶制备方法上的研究进展,探讨了DNA水凝胶的分类策略,并进一步综述了DNA水凝胶在药物运输、生物传感、细胞培养等方面的应用研究。最后对DNA水凝胶未来的发展方向以及可能面临的挑战进行了展望。 相似文献
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Sunil Gujjar Anurag Tyagi Saloni Sainger Puja Bharti Vaibhav Nain Pratibha Sood Prakash Jayabal Jagadish Chandra Sharma Priyanka Sharma Sanjay Rajput Anil Kumar Pandey Amit Kumar Pandey Prasad Abnave Santosh Mathapati 《Advanced Biosystems》2024,8(1):2300349
Solubilizing extracellular matrix (ECM) materials and transforming them into hydrogels has expanded their potential applications both in vitro and in vivo. In this study, hydrogels are prepared by decellularization of human placental tissue using detergent and enzymes and by the subsequent creation of a homogenized acellular placental tissue powder (P-ECM). A perfusion-based decellularization approach is employed using detergent and enzymes. The P-ECM with and without gamma irradiation is then utilized to prepare P-ECM hydrogels. Physical and biological evaluations are conducted to assess the suitability of the P-ECM hydrogels for biocompatibility. The decellularized tissue has significantly reduced cellular content and retains the major ECM proteins. Increasing the concentration of P-ECM leads to improved mechanical properties of the P-ECM hydrogels. The biocompatibility of the P-ECM hydrogel is demonstrated through cell proliferation and viability assays. Notably, gamma-sterilized P-ECM does not support the formation of a stable hydrogel. Nonetheless, the use of HCl during the digestion process effectively decreases spore growth and bacterial bioburden. The study demonstrates that P-ECM hydrogels exhibit physical and biological attributes conducive to soft tissue reconstruction. These hydrogels establish a favorable microenvironment for cell growth and the need for investigating innovative sterilization methods. 相似文献
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Luman Liu Jared A. Shadish Christopher K. Arakawa Kevin Shi Jennifer Davis Cole A. DeForest 《Advanced Biosystems》2018,2(12):1800240
Although mechanical signals presented by the extracellular matrix are known to regulate many essential cell functions, the specific effects of these interactions, particularly in response to dynamic and heterogeneous cues, remain largely unknown. Here, a modular semisynthetic approach is introduced to create protein–polymer hydrogel biomaterials that undergo reversible stiffening in response to user-specified inputs. Employing a novel dual-chemoenzymatic modification strategy, fusion protein-based gel crosslinkers are created that exhibit stimuli-dependent intramolecular association. Linkers based on calmodulin yield calcium-sensitive materials, while those containing the photosensitive light, oxygen, and voltage sensing domain 2 (LOV2) protein give phototunable constructs whose moduli can be cycled on demand with spatiotemporal control about living cells. These unique materials are exploited to demonstrate the significant role that cyclic mechanical loading plays on fibroblast-to-myofibroblast transdifferentiation in 3D space. The moduli-switchable materials should prove useful for studies in mechanobiology, providing new avenues to probe and direct matrix-driven changes in 4D cell physiology. 相似文献
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Isabella Nymann Westensee Karen Louise Thomsen Rajeshwar Prosad Mookerjee Brigitte Städler 《Advanced Biosystems》2024,8(4):2300547
Access to therapeutic strategies that counter cellular stress induced by reactive oxygen species (ROS) is an important, long-standing challenge. Here, the assembly of antioxidant artificial cells is based on alginate hydrogels equipped with non-native catalysts, namely platinum nanoparticles and an EUK compound. These artificial cells are able to preserve the viability and lower the intracellular ROS levels of challenged hepatic cells by removing peroxides from the extracellular environment. Conceptually, this strategy illustrates the potential use of artificial cells with a synthetic catalyst toward long-term support of hepatic cells and potentially other mammalian cells. 相似文献
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David W. Green Jolanta A. Watson Gregory S. Watson Artemis Stamboulis 《Advanced Biosystems》2020,4(8)
The efficient genesis of pluripotent cells or therapeutic cells for regenerative medicine involves several external manipulations and conditioning protocols, which drives down clinical applicability. Automated programming of the genesis by microscale physical forces and chronological biochemistry can increase clinical success. The design and fabrication of nested polysaccharide droplets (millimeter‐sized) with cell sustaining properties of natural tissues and intrinsic properties for time and space evolution of cell transformation signals between somatic cells, pluripotent cells and differentiated therapeutic cells in a swift and efficient manner without the need for laborious external manipulation are reported. Cells transform between phenotypic states by having single and double nested droplets constituted with extracellular matrix proteins and reprogramming, and differentiation factors infused chronologically across the droplet space. The cell transformation into germ layer cells and bone cells is successfully tested in vitro and in vivo and promotes the formation of new bone tissues. Thus, nested droplets with BMP‐2 loaded guests synthesize mineralized bone tissue plates along the length of a cranial non‐union bone defect at 4 weeks. The advantages of sequenced somatic cell reprogramming and differentiation inside an individual hydrogel module without external manipulation, promoted by formulating tissue mimetic physical, mechanical, and chemical microenvironments are shown. 相似文献