Stiffness‐Controlled Thermoresponsive Hydrogels for Cell Harvesting with Sustained Mechanical Memory. Issue 5 (20th January 2017)

• Record Type: Journal Article
• Authors: Fan, Xingliang; Zhu, Lu; Wang, Ke; Wang, Bingjie; Wu, Yaozu; Xie, Wei; Huang, Chengyu; Chan, Barbara Pui; Du, Yanan
• Is Part Of: Advanced healthcare materials. Volume 6:Issue 5(2017)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2017-01-20
• Subjects: mechanical memory -- mechanobiology -- stiffness‐control -- thermoresponsive hydrogels -- wound healing; Biomedical materials -- Periodicals; 610.28
• DOI: 10.1002/adhm.201601152
• Languages: English
• ISSNs: 2192-2640

Abstract

Abstract : Most mechanobiological investigations focused on in situ mechanical regulation of cells on stiffness‐controlled substrates with few downstream applications, as it is still challenging to harvest and expand mechanically primed cells by enzymatic digestion (e.g., trypsin) without interrupting cellular mechanical memory between passages. This study develops thermoresponsive hydrogels with controllable stiffness to generate mechanically primed cells with intact mechanical memory for augmented wound healing. No significant cellular property alteration of the fibroblasts primed on thermoresponsive hydrogels with varied stiffness has been observed through thermoresponsive harvesting. When reseeding the harvested cells for further evaluation, softer hydrogels are proven to better sustain the mechanical priming effects compared to rigid tissue culture plate, which indicates that both the stiffness‐controlled substrate and thermoresponsive harvesting are required to sustain cellular mechanical memory between passages. Moreover, epigenetics analysis reveals that thermoresponsive harvesting could reduce the rearrangement and loss of chromatin proteins compared to that of trypsinization. In vivo wound healing using mechanically primed fibroblasts shows featured epithelium and sebaceous glands, which indicates augmented skin recovery compared with trypsinized fibroblasts. Thus, the thermoresponsive hydrogel‐based cell harvesting system offers a powerful tool to investigate mechanobiology between cell passages and produces abundant cells with tailored mechanical priming properties for cell‐based applications. Abstract : A stiffness‐controlled thermoresponsive hydrogel system is developed based on N‐isopropylacrylamide (NIPAm) and poly (ethylene glycol) (PEG) macromonomers for sustaining the cellular mechanical memory between passages. Such a system provides not only a powerful tool in biomechanical investigation, but also high‐quality cell cource with tailored mechanical properties for cell‐based therapeutic applications.