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Garrido, C. A.

Publications and source records attributed to Garrido, C. A..

5 recordsLinked to original sources

Patterned alginate hydrogel spatially guides collagen fibrillogenesis, viscoelasticity and endothelial cell invasion

Angiogenesis following injury has been shown to be driven by fibrillar proteins of the extracellular matrix (ECM), such as collagen. However, the use of protein-based biomaterials presents some challenges, such as uncontrolled degradation and limited tuneability. We demonstrate how to create patterned interpenetrating networks (IPNs) based on covalently crosslinked alginate and physically crosslinked collagen that provide suitable mechanical properties to support migration of endothelial cells (ECs) in a spatially controlled manner. Low molecular weight alginate is functionalized with norbornene (N) or tetrazine (T), which enables two independent covalent crosslinking methods: UV-mediated and degradable crosslinks with matrix metalloproteinase (MMP) sensitive peptides (Deg) and slower spontaneous N:T non-degradable crosslinks (noDeg). Using photolithography, patterns in degradation, collagen fibrillogenesis, microarchitecture and matrix viscoelasticity are created. The potential of such 3D patterned alginate-collagen (Alg-Col) IPNs to spatially guide EC invasion and proliferation was tested in a microfluidics platform resembling an early healing setting. Only regions combining collagen fibrillogenesis, alginate degradability and viscoelasticity demonstrated EC cell invasion similar to the ones found in vivo following injury. The 3D patterned Alg-Col IPNs are compatible with microfluidics, offer an strategy to widen the applications of protein-based hydrogels and present a versatile platform for tissue engineering and disease modeling.

bioengineering↗

Structural guidance in 3D microgel-in-hydrogel systems to improve chondrogenesis

Anisotropic biomaterials are broadly studied in regenerative medicine as they aim to mimic the hierarchical structures of native tissue. The Anisogel, an anisotropic microgel-in-hydrogel system, involves two key factors for tissue engineering: guidance cues - magnetically aligned rod-shape structures - and a surrounding matrix - polyethylene glycol-vinylsulfone (PEG-VS) with a degradable peptide crosslinker. This research shows the potential of using a PEG-VS-based Anisogel to allow for guided ingrowth and chondrogenic differentiation of human mesenchymal stromal cells (hMSCs) modulated by the alignment and size of anisometric microgels. The properties of the surrounding matrix are optimized for the availability of anchoring peptides (RGD concentration) and matrix density (hydrogel precursor concentration). The microgels of highest tested dimensions (10x10x100 {micro}m3) lead to a donor-independent significant upregulation of chondrogenic markers (SOX 9, ACAN and COL2AI) and a decrease of hypertrophic chondrogenic markers (RUNX 2), compared to unaligned and smaller microgel sizes. As a proof of concept, the Anisogel is tested in a semi-orthotopic mouse model where the effect of microgel alignment on cell infiltration and osteochondral tissue formation is evaluated.

bioengineering↗

3D patterns in alginate hydrogel degradation spatially guide YAP nuclear translocation and hMSC osteogenic differentiation

Tissue engineering involves assembling cells and mimicking the complex anisotropic architecture of biological tissues to perform specific functions. This study explores the impact of patterned hydrogels with anisotropic degradation compared to single-phase materials on the potential of enhancing cell spreading, collective alignment, mechanotransduction and osteogenic differentiation of encapsulated human mesenchymal stromal cells (hMSCs). Spatial patterns of degradable (Deg) and non-degradable (noDeg) subregions are formed by photolithography: UV-triggered thiol-ene crosslinking with matrix metalloprotease (MMP) sensitive peptides form Deg phases, while non-UV exposed regions result in Diels-Alder spontaneous click crosslinking and noDeg phases. 3D patterns in hydrogel degradation enhance hMSC spreading and allow collective cell alignment in Deg areas, while cells remain rounded with no alignment in noDeg regions. In addition, we observe a boosted osteogenic differentiation when compared to single-phase materials, as mid osteogenic markers (osteocalcin) are expressed at day 14 in anisotropic gels, whereas in single-phase only early osteogenic markers are found (osterix). Mechanosensing pathways were evaluated using the expression and localization of YAP. Deg sections in patterned materials have an enhanced nuclear translocation and higher YAP expression compared to single-phase Deg materials and noDeg sections. This effect is lost and no patterns in YAP expression and localization emerge when using an MMP-scramble peptide or no-RGD materials. These findings demonstrate that 3D patterns in alginate hydrogel degradation guide hMSC spreading, collective alignment, enhance YAP nuclear translocation and osteogenic differentiation. Mimicking tissue anisotropy in 3D patterned hydrogels could have broad applications in biofabrication and tissue engineering. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=79 SRC="FIGDIR/small/588803v3_ufig1.gif" ALT="Figure 1"> View larger version (34K): org.highwire.dtl.DTLVardef@f7aa3aorg.highwire.dtl.DTLVardef@1c8d2a4org.highwire.dtl.DTLVardef@17d2371org.highwire.dtl.DTLVardef@a1d6a2_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical AbstractC_FLOATNO C_FIG

bioengineering↗

Aging impairs muscle regeneration by desynchronizing matrix mechano-signaling and macrophage immunomodulation via fibro-adipogenic progenitors

Skeletal muscle regeneration depends on the function of fibro/adipogenic progenitors (FAPs). Here we show that aging impairs myogenic stem cells by disrupting the integration of extracellular matrix and immunomodulatory functions within the stem cell niche, thereby promoting fibro/fatty degeneration. We identify the FAP-secreted protein Periostin as a niche factor that is decreased in aged muscle and in circulation of aged humans with low-exercise lifestyle. Periostin controls FAP-expansion after injury and its depletion fate-regulates FAPs towards adipogenesis. This leads to delayed pro- to anti-inflammatory macrophage transition during regeneration. Transplantation of young FAPs with high Periostin secretion, but not Periostin-deficient FAPs, into aged muscle restores inflammation resolution and successful regeneration. Mechanistically, Periostin activates Focal adhesion kinase- and AKT-signaling in macrophages via integrins to promote an anti-inflammatory profile, which synchronizes matrix-derived mechanosensory signaling and immunomodulation. These results uncover a novel role of FAP-based regulation that orchestrates successful muscle regeneration and prevents fibro/fatty degeneration.

physiology↗

Hydrogels with stiffness-degradation spatial patterns control anisotropic 3D cell response

In nature, tissues are patterned, but most biomaterials used in human applications are not. Patterned biomaterials offer the opportunity to mimic spatially segregating biophysical and biochemical properties found in nature. Engineering such properties allows to study cell-matrix interactions in anisotropic matrices in great detail. Here, we developed alginate-based hydrogels with patterns in stiffness and degradation, composed of distinct areas of soft non-degradable (Soft-NoDeg) and stiff degradable (Stiff-Deg) material properties. The hydrogels exhibit emerging patterns in stiffness and degradability over time, taking advantage of dual Diels-Alder covalent crosslinking and UV-mediated peptide crosslinking. The materials were mechanically characterized using rheology for single-phase and surface micro-indentation for patterned materials. 3D encapsulated mouse embryonic fibroblasts (MEFs) allowed to characterize the anisotropic cell-matrix interaction in terms of cell morphology by employing a novel image-based quantification tool. Live/dead staining showed no differences in cell viability but distinct patterns in proliferation, with higher cell number in Stiff-Deg materials at day 14. Patterns of projected cell area became visible already at day 1, with larger values in Soft-NoDeg materials. This was inverted at day 14, when larger projected cell areas were identified in Stiff-Deg. This shift was accompanied by a significant decrease in cell circularity in Stiff-Deg. The control of anisotropic cell morphology by the material patterns was also confirmed by a significant increase in filopodia number and length in Stiff-Deg materials. The novel image-based quantification tool was useful to spatially visualize and quantify the anisotropic cell response in 3D hydrogels with stiffness-degradation spatial patterns. Our results show that patterning of stiffness and degradability allows to control cell anisotropic response in 3D and can be quantified by image-based strategies. This allows a deeper understanding of cell-matrix interactions in a multicomponent material.

bioengineering↗