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- Petrou, Cassandra L., et al.
(författare)
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Clickable decellularized extracellular matrix as a new tool for building hybrid-hydrogels to model chronic fibrotic diseases in vitro
- 2020
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Ingår i: Journal of Materials Chemistry B. - 2050-7518. ; 8:31, s. 6814-6826
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Tidskriftsartikel (refereegranskat)abstract
- Fibrotic disorders account for over one third of mortalities worldwide. Despite great efforts to study the cellular and molecular processes underlying fibrosis, there are currently few effective therapies. Dual-stage polymerization reactions are an innovative tool for recreating heterogeneous increases in extracellular matrix (ECM) modulus, a hallmark of fibrotic diseases in vivo. Here, we present a clickable decellularized ECM (dECM) crosslinker incorporated into a dynamically responsive poly(ethylene glycol)-α-methacrylate (PEGαMA) hybrid-hydrogel to recreate ECM remodeling in vitro. An off-stoichiometry thiol-ene Michael addition between PEGαMA (8-arm, 10 kg mol-1) and the clickable dECM resulted in hydrogels with an elastic modulus of E = 3.6 ± 0.24 kPa, approximating healthy lung tissue (1-5 kPa). Next, residual αMA groups were reacted via a photo-initiated homopolymerization to increase modulus values to fibrotic levels (E = 13.4 ± 0.82 kPa) in situ. Hydrogels with increased elastic moduli, mimicking fibrotic ECM, induced a significant increase in the expression of myofibroblast transgenes. The proportion of primary fibroblasts from dual-reporter mouse lungs expressing collagen 1a1 and alpha-smooth muscle actin increased by approximately 60% when cultured on stiff and dynamically stiffened hybrid-hydrogels compared to soft. Likewise, fibroblasts expressed significantly increased levels of the collagen 1a1 transgene on stiff regions of spatially patterned hybrid-hydrogels compared to the soft areas. Collectively, these results indicate that hybrid-hydrogels are a new tool that can be implemented to spatiotemporally induce a phenotypic transition in primary murine fibroblasts in vitro.
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| 2. |
- Petrou, Cassandra L., et al.
(författare)
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Clickable, hybrid hydrogels as tissue culture platforms for modeling chronic pulmonary diseases in vitro
- 2019
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Ingår i: Society for Biomaterials Annual Meeting and Exposition 2019 : The Pinnacle of Biomaterials Innovation and Excellence - Transactions of the 42nd Annual Meeting - The Pinnacle of Biomaterials Innovation and Excellence - Transactions of the 42nd Annual Meeting. - 9781510883901 ; 40
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Konferensbidrag (refereegranskat)abstract
- Statement of Purpose: Many chronic pulmonary diseases, including idiopathic pulmonary fibrosis (IPF), pulmonary hypertension (PH) and chronic obstructive pulmonary disease (COPD), are complex and poorly understood. While great progress has been made to elucidate the cellular and molecular pathways underlying these diseases, treatment options remain limited. The dynamic alterations in mechanical properties and composition of the ECM that occur during pathologic tissue remodeling have been extensively studied as a major driver of cellular activation and disease progression. However, current in vitro models of pulmonary tissues rely almost exclusively on naturally derived materials, such as Matrigel, collagen or decellularized ECM (dECM), which provide biological activity but cannot be easily tuned to emulate the time-dependent changes in mechanical properties that occur during disease progression. We aim to develop a new class of clickable, dynamically tunable hybrid hydrogels that will allow for the manipulation of microenvironmental mechanical properties through a two-stage polymerization process while also maintaining the complex biological composition of the lung ECM to provide a new tool for studying cell behavior in vitro. Using PH as a model, this hydrogel system will contain dECM from healthy and pathologic lung tissue in order to study the influence of both composition and dynamic mechanical properties on the initiation and progression of PH. Here, we determined the primary amine content in Rat-Tail Collagen Type I (Col I) and three decellularized porcine lung samples. We converted free amines to thiol groups using Traut’s reagent. These thiol groups will ultimately be used to crosslink polyethylene glycol alpha methacrylate (PEGαMA) off-stoichiometry in a Michael addition reaction to form the hybrid hydrogel that can later be stiffened through a secondary, light-initiated homopolymerization of MA moieties to emulate disease progression in vitro (Fig 1A).
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