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D'Este, M.

Publications and source records attributed to D'Este, M..

4 recordsLinked to original sources

Modulation of Neutrophil Function by Foetal Bovine Serum and Type I Collagen

Immune regulation plays a crucial role during the regeneration process, and it determines the fate of inflammation after tissue injury or infection. Neutrophils serve as the primary immune cells recruited to the site of inflammation, initiating and directing the subsequent inflammatory cascade following implantation. As neutrophils are highly sensitive to environmental cues, commonly used culture supplements and molecules may themselves influence neutrophil function and consequently affect the interpretation of biomaterial-induced immune responses. This study examined how foetal bovine serum (FBS), a standard in vitro culture supplement, affects human peripheral blood neutrophils when supplied either in the culture medium or as a surface coating on 3D-printed polycaprolactone (PCL) scaffolds. The response to type I collagen coating was also assessed as a biologically relevant comparator. Neutrophil activity was evaluated by assessing metabolic activity and metabolomic profiles, reactive oxygen species (ROS) production, and inflammation-related markers via a high-throughput proximity extension assay. Type I collagen coating modified the metabolomic profile of neutrophils and MMP-9 release but had minimal effect on ROS generation. In contrast, the presence of FBS in the culture medium significantly influenced neutrophil behavior, leading to significant changes in metabolic activity, cytotoxicity, and the secretion of inflammation-associated molecules, even at concentrations as low as 1% (v/v). These findings highlight the importance of assessing the use of FBS in neutrophil culture models, particularly those isolated from humans, and emphasize the need to develop alternative platforms for investigating neutrophil-biomaterial interactions in a more physiologically relevant manner.

immunology↗

Effect of molecular weight of tyramine-modified hyaluronan on polarization state of peripheral blood mononuclear cells-derived macrophages

The immunomodulatory properties of hyaluronan and its derivatives are key to their use in medicine and tissue engineering. In this work we evaluated the capability of soluble tyramine-modified hyaluronan (THA) of two molecular weights (low Mw=280 kDa and high Mw=1640 kDa) for polarization of THP-1 and peripheral blood mononuclear cells (PBMCs)-derived macrophages (M{Phi}s). We demonstrate the polarization effects of the supplemented THA by flow cytometry and multiplex ELISA for the THP-1 derived M{Phi}s and by semi-automated image analysis from confocal microscopy, immunofluorescent staining utilising CD68 and CD206 surface markers, RT-qPCR gene expression analysis, as well as using the enzyme-linked immunosorbent assay (ELISA) for PBMCs-derived M{Phi}s. Our data indicate that supplementation with LMW THA drives changes in THP-1 derived M{Phi}s towards a pro-inflammatory M1-like phenotype, whereas supplementation with the HMW THA leads to a more mixed profile with some features of both M1 and M2 phenotypes, suggesting either a heterogeneous population or a transitional state. For cells directly sourced from human patients, PMBCs-derived M{Phi}s, results exhibit a higher degree of variability, pointing out a differential regulation of factors including IL-10 and CD206 between the two cell sources. While human primary cells add to the clinical relevance, donor diversity introduces wider variability in the dataset, preventing drawing strong conclusions. Nevertheless, the M{Phi}s profiles observed in THP-1 derived cells for treatments with LMW and HMW THA are generally consistent with what might be expected for the treatment with non-modified hyaluronans of respective molecular weights, confirming the known association holds true for the chemically tyramine-modified hyaluronan. We stipulate that these responses will provide basis for more accurate in vivo representation and translational immunomodulatory guidance for the use of THA-based biomaterials to a wider biomaterials and tissue engineering communities. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=114 SRC="FIGDIR/small/575241v3_ufig1.gif" ALT="Figure 1"> View larger version (24K): org.highwire.dtl.DTLVardef@899d95org.highwire.dtl.DTLVardef@c8b80aorg.highwire.dtl.DTLVardef@1aad98dorg.highwire.dtl.DTLVardef@1b0ce60_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioengineering↗

The Impact of the Local Mechanical Environment on Cell Shape and Chondrogenesis of Mesenchymal Stromal Cells in 3D Biomimetic Composite Materials

Efforts to model and repair connective tissue through engineered tissue constructs have generated great interest in culturing cells in 3d polymer network environments. It has been shown that the polymer environment is influential in determining cellular responses such as differentiation, migration and morphology. Hydrogels are used to mimic the cellular microenvironment, but in most cases hydrogels consisting of one polymeric component are used whereas tissues are composites of different polymers. A clear understanding of how different extracellular components and their mechanical characteristics influence cell behaviour is lacking. Here we developed and characterised composite hydrogels of hyaluronan and fibrin and evaluated their use for cartilage tissue engineering. We demonstrate that these cartilage-mimicking composites have a higher stiffness relative to the individual constituents. Next, we cultured human mesenchymal stromal cells in these 3D hydrogels with chondrogenic media and revealed marked differences in cell morphology, gene expression and cartilage-like matrix deposition depending on the specific extracellular composition. We found that, despite evidence for strong adhesion of the cells to fibrin networks in 2D systems, in 3D systems the primary determinant of cellular morphology is the significantly denser hyaluronan network. Dense hyaluronan hydrogels cause local cell confinement evidenced by rounder cell morphologies, independent of the presence of fibrin. While the composite fibrin-hyaluronan hydrogels led to lower expression of chondrogenic genes than hyaluronan alone, the larger linear modulus and resistance to cell-mediated contraction due to the composite nature of the matrix provides a strong advantage in terms of macroscopic mechanical stability. These findings highlight the potential of multi-component hydrogels for controlling cellular behaviour and bulk mechanical properties of cell-hydrogel constructs independently, therefore opening avenues for better understanding the complex interplay between cells and their extracellular environment and thus improve the biofabrication of connective tissues for disease modelling and tissue regeneration. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=127 SRC="FIGDIR/small/555478v1_ufig1.gif" ALT="Figure 1"> View larger version (35K): org.highwire.dtl.DTLVardef@151962org.highwire.dtl.DTLVardef@1358890org.highwire.dtl.DTLVardef@198dcedorg.highwire.dtl.DTLVardef@d04f80_HPS_FORMAT_FIGEXP M_FIG C_FIG

biophysics↗

Tissue mimetic hyaluronan bio-ink containing oriented collagen fibers to modulate hMSC spreading and differentiation

Biofabrication is providing scientists and clinicians the ability to produce engineered tissues with desired shapes, and gradients of composition and biological cues. Typical resolutions achieved with extrusion-based bioprinting are at the macroscopic level. However, for capturing the fibrillar nature of the extracellular matrix (ECM), it is necessary to arrange ECM components at smaller scales, down to the micron and the molecular level. In this study, we introduce a bioink containing hyaluronan (HA) as tyramine derivative (THA) and collagen type 1 (Col 1). Similarly to other connective tissues, in this bioink Col is present in fibrillar form and HA as viscoelastic space filler. THA was enzymatically crosslinked under mild conditions allowing simultaneous Col fibrillogenesis, thus achieving a homogeneous distribution of Col fibrils within the viscoelastic HA-based matrix. THA-Col composite displayed synergistic properties in terms of storage modulus and shear-thinning, translating into good printability. Shear-induced alignment of the Col fibrils along the printing direction was achieved and quantified via immunofluorescence and second harmonic generation. Cell-free and cell-laden constructs were printed and characterized, analyzing the influence of the controlled microscopic anisotropy on human bone marrow derived mesenchymal stromal cells (hMSC) migration. THA-Col showed cell instructive properties modulating hMSC adhesion, morphology and sprouting from spheroids stimulated by the presence and the orientation of Col fibers. Actin filament staining showed that hMSCs embedded into aligned constructs displayed increased cytoskeleton alignment along the fibril direction. Based on gene expression of cartilage/bone markers and ECM production, hMSCs embedded into the bioink displayed chondrogenic differentiation comparable to standard pellet culture by means of proteoglycan production (Safranin O staining and proteoglycan quantification). The possibility of printing matrix components with control over microscopic alignment brings biofabrication one step closer to capturing the complexity of native tissues.

bioengineering↗