Biology subjects

Malandrino, A.

Publications and source records attributed to Malandrino, A..

4 recordsLinked to original sources

bioRxiv2026

Integration of In-Line Light-Mediated Cell Activation in Extrusion-Based Bioprinting: A New Biofabrication Strategy for Bone Tissue Engineering

Controlled activation of cells through photobiomodulation can influence osteogenic outcomes. However, factors such as skin penetration depth limit its clinical relevance. In this study, we present a workflow integrating broadband light stimulation directly into the bioprinting process by equipping a custom, low-cost extrusion bioprinter with a self-made, high-voltage spark-gap stimulation unit, enabling in-line stimulation of cells embedded in hydrogel. Optimal duration of broadband light exposure was screened with SaOS-2 cells in 2D for 5, 10, or 15 min, and cultured under osteogenic and control conditions. In 3D, SaOS-2 or adipose-derived stromal cells (ASCs) were bioprinted in an alginate-gelatin bioink under 10 minutes of pulsatile light stimulation. Cellular responses were assessed after 21 days by cell yield, viability, metabolic activity, apoptosis, DNA damage and osteogenic differentiation through immunofluorescence, histology and qPCR. Additionally, vascularisation capacity was assessed in light-stimulated HUVEC/ASC co-cultures within bioprinted constructs. In 2D, light stimulation did not negatively affect cell yield, viability, metabolic activity, cytotoxicity and DNA damage across all exposure times. 3D cultures showed a 2.7-fold and 2.4-fold increase in calcium and hydroxyapatite, respectively, elevated osteocalcin/collagen type I protein expression and gene expression of ALPL, BGLAP, SPP-1, COL1A1, COL10A1 and no increase in DNA damage after 21 days. In the HUVEC/ASC co-culture, light stimulation promoted endothelial elongation (1.25-fold), network formation (2-fold) and perivascular ASC organisation. This work establishes a proof-of-concept methodology for in-line, broadband light cell activation during bioprinting as a strategy to enhance osteogenic differentiation and vascularisation potential.

bioengineering↗

bioRxiv2025

Bioconvergence of sound-guided and supramolecular assembly strategies to create peptide-protein composite hydrogels with predictable shape-to-function features

Purely protein-based hydrogels are widely used in tissue engineering for their biomimicry and biocompatibility, yet remain challenging to tailor with precision and predictability at biological and mechanical levels. To overcome this, synthetic self-assembling peptide amphiphiles (PAs) offer opportunities for supramolecular customization, both as single-phase materials and co-assembled with proteins to create hybrid nanocomposites with emerging functionalities. Similarly, contactless, sound-guided bioassembly techniques using liquid-phase hydrogel precursors are emerging as strategic tools for obtaining structured and functional hydrogels. Leveraging these advances, here a fast, contactless, one-pot bioassembly strategy merging supramolecular PA self-assembly with sound-guided patterning to fabricate hybrid peptide-protein hydrogels with programmable shape-to-function features is presented. Using fibrin as proof-of-concept, material performance is biologically enhanced by incorporating growth factor-binding PAs, while inorganic microparticles are embedded and spatially organized via acoustic fields to tune mechanical properties. This strategy allows predictable tuning of composite stiffness and architecture by adjusting sound wave frequency, with acoustic fields guiding material organization from micro-to-macroscale. Composite hydrogels result highly permissive to cell infiltration in vitro and versatile platform to tune immune cell-material interactions. This modular biofabrication platform integrating supramolecular and sound-guided processes can be generalized to other building blocks opening unique opportunities for scalable, tunable, and hierarchically-organized biomaterials.

bioengineering↗

bioRxiv2023

Fiber alignment in 3D collagen networks as a biophysical marker for cell contractility

Cells cultured in 3D fibrous biopolymer matrices exert traction forces on their environment that induce deformations and remodeling of the fiber network. By measuring these deformations, the traction forces can be reconstructed if the mechanical properties of the matrix and the force-free matrix configuration are known. These requirements severely limit the applicability of traction force reconstruction in practice. In this study, we test whether force-induced matrix remodeling can instead be used as a proxy for cellular traction forces. We measure the traction forces of hepatic stellate cells and different glioblastoma cell lines and quantify matrix remodeling by measuring the fiber orientation and fiber density around these cells. In agreement with simulated fiber networks, we demonstrate that changes in local fiber orientation and density are directly related to cell forces. By resolving Rho-kinase (ROCK) Inhibitor-induced changes of traction forces and fiber alignment and density in hepatic stellate cells, we show that the method is suitable for drug screening assays. We conclude that differences in local fiber orientation and density, which are easily measurable, can be used as a qualitative proxy for changes in traction forces. The method is available as an open-source Python package with a graphical user interface.

biophysics↗

bioRxiv2017

Non-Elastic Remodeling of the 3D Extracellular Matrix by Cell-Generated Forces

The mechanical properties of the extracellular matrix (ECM) - a complex, 3D, fibrillar scaffold of cells in physiological environments - modulate cell behavior and can drive tissue morphogenesis, regeneration, and disease progression. For simplicity, it is often convenient to assume these properties to be time-invariant. In living systems, however, cells dynamically remodel the ECM and create time-dependent local environments. Here, we demonstrate that cell generated contractile forces are capable of producing substantial irreversible changes to the density and architecture of physiologically relevant ECMs - collagen I and fibrin - in a matter of minutes. We measure the 3D mechanical deformation profiles of the ECM surrounding cancer and endothelial cells during stages when force generation is active or inactive. We further correlate these measurements to both discrete fiber simulations that incorporate fiber crosslink unbinding kinetics and continuum-scale modeling. Our findings reveal that plasticity, as a mechanical law in these networks, is fundamentally related to the force-driven unbinding of fiber crosslinks. These results illustrate the dynamic nature of the mechanical environment of physiologically mimicking cell-in-gel systems.

bioengineering↗