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Title: Engineering human spinal microphysiological systems to model opioid-induced tolerance
Dynamic regulation of cell-extracellular matrix (ECM)-material interactions is crucial for various biomedical applications. In this study, a light-activated molecular switch for the modulation of cell attachment/detachment behaviors was established on monolayer graphene (Gr)/n-type Silicon substrates (Gr/Si). Initiated by light illumination at the Gr/Si interface, pre-adsorbed proteins (bovine serum albumin, ECM proteins collagen-1, and fibronectin) underwent protonation to achieve negative charge transfer to Gr films (n-doping) through π-π interactions. This n-doping process stimulated the conformational switches of ECM proteins. The structural alterations in these ECM interactors significantly reduced the specificity of the cell surface receptor-ligand interaction (e.g., integrin recognition), leading to dynamic regulation of cell adhesion and eventual cell detachment. RNA-sequencing results revealed that the detached bone marrow mesenchymal stromal cell sheets from the Gr/Si system manifested regulated immunoregulatory properties and enhanced osteogenic differentiation, implying their potential application in bone tissue regeneration. This work not only provides a fast and feasible method for controllable cells/cell sheets harvesting but also gives new insights into the understanding of cell-ECM-material communications.  more » « less
Award ID(s):
2134257
PAR ID:
10476467
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Editor(s):
Jian Yang
Publisher / Repository:
Bioactive Materials
Date Published:
Journal Name:
Bioactive Materials
Edition / Version:
1
Volume:
22
Issue:
C
ISSN:
2452-199X
Page Range / eLocation ID:
482 to 490
Subject(s) / Keyword(s):
In-situ electrical sensing Microphysiological systems Neural activity Opioid-induced tolerance and hyperalgesia Organ-on-chip Spinal cord organoids
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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