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- Paidikondala, Maruthibabu, 1985-, et al.
(författare)
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An Unexpected Role of Hyaluronic Acid in Trafficking siRNA Across the Cellular Barrier : The First Biomimetic, Anionic, Non-Viral Transfection Method
- 2019
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Ingår i: Angewandte Chemie International Edition. - : WILEY-V C H VERLAG GMBH. - 1433-7851 .- 1521-3773. ; 58:9, s. 2815-2819
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Tidskriftsartikel (refereegranskat)abstract
- Circulating nucleic acids, such as short interfering RNA (siRNA), regulate many biological processes; however, the mechanism by which these molecules enter the cell is poorly understood. The role of extracellular-matrix-derived polymers in binding siRNAs and trafficking them across the plasma membrane is reported. Thermal melting, dynamic light scattering, scanning electron microscopy, and computational analysis indicate that hyaluronic acid can stabilize siRNA via hydrogen bonding and Van der Waals interactions. This stabilization facilitated HA size- and concentration-dependent gene silencing in a CD44-positive human osteosarcoma cell line (MG-63) and in human mesenchymal stromal cells (hMSCs). This native HA-based siRNA transfection represents the first report on an anionic, non-viral delivery method that resulted in approximately 60% gene knockdown in both cell types tested, which correlated with a reduction in translation levels.
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| 2. |
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| 3. |
- Yan, Hongji, et al.
(författare)
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Synthetic design of growth factor sequestering extracellular matrix mimetic hydrogel for promoting in vivo bone formation
- 2018
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Ingår i: Biomaterials. - : Elsevier. - 0142-9612 .- 1878-5905. ; 161, s. 190-202
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Tidskriftsartikel (refereegranskat)abstract
- Synthetic scaffolds that possess an intrinsic capability to protect and sequester sensitive growth factors is a primary requisite for developing successful tissue engineering strategies. Growth factors such as recombinant human bone morphogenetic protein-2 (rhBMP-2) is highly susceptible to premature degradation and to provide a meaningful clinical outcome require high doses that can cause serious side effects. We discovered a unique strategy to stabilize and sequester rhBMP-2 by enhancing its molecular interactions with hyaluronic acid (HA), an extracellular matrix (ECM) component. We found that by tuning the initial protonation state of carboxylic acid residues of HA in a covalently crosslinked hydrogel modulate BMP-2 release at physiological pH by minimizing the electrostatic repulsion and maximizing the Van der Waals interactions. At neutral pH, BMP-2 release is primarily governed by Fickian diffusion, whereas at acidic pH both diffusion and electrostatic interactions between HA and BMP-2 become important as confirmed by molecular dynamics simulations. Our results were also validated in an in vivo rat ectopic model with rhBMP-2 loaded hydrogels, which demonstrated superior bone formation with acidic hydrogel as compared to the neutral counterpart. We believe this study provides new insight on growth factor stabilization and highlights the therapeutic potential of engineered matrices for rhBMP-2 delivery and may help to curtail the adverse side effects associated with the high dose of the growth factor.
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| 4. |
- Yan, Hongji, et al.
(författare)
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Tuning biomaterial pH for regulating BMP-2 stability and bioactivity in vitro and in vivo
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Annan publikation (populärvet., debatt m.m.)abstract
- The poor affinity of rhBMP-2 to the scaffolds leads to high dose administration requirement resulted in massive side effects has been the hurdle for successful clinic translation for treating delayed unions or remained non-union at bone defect. Optimizing the scaffolds with the purpose of obtaining optimal BMP2 dose and release have been addressed as critical for BMP-2 administration, however, the results are contradictory concerning whether bone formation is more beneficial from burst or controlled release of BMP2. While this might be due to these studies incorporated other bioactive molecules onto scaffolds to immobilize BMP-2. In this study, we report the affinities of rhBMP-2 to the scaffolds can be improved by only tuning the pH of hyaluronic acid (HA) hydrazone crosslinking hydrogel without addition of other molecules. Neo bone induced by BMP-2 showed significantly higher volume with more impact structure and vascularization in pH 4.5 HA hydrogel compared to that in pH7 HA hydrogel. The mechanisms were demonstrated by In vitro BMP-2 release followed by diffusion quantitative calculation and computational simulation methods. Initial burst release of BMP-2 from pH 7 HA hydrogels with the fitting of Fickian behavior while sustained release from pH 4.5 HA hydrogel was observed. Computational stimulation revealed this is due to the protonation state of BMP2 at pH 4.5 resulted in stronger electrostatic interaction with negatively charged groups along the backbone of hyaluronic acid molecules compared to at pH 7. This study gives new direction to scaffolds designing for basic bioactive protein applications in future.
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