RGD-mediated membrane-matrix adhesion triggers agarose-induced embryoid formation in sunflower protoplasts

The present work investigated the possibility to use wet blue (WB) leather wastes as natural reinforcing fibers within different polymer matrices. After their preparation and characterization, WB fibers were melt-mixed at 10 wt.% with poly(lactic acid) (PLA), polyamide 12 (PA12), thermoplastic elastomer (TPE), and thermoplastic polyurethane (TPU), and the obtained samples were subjected to rheological, thermal, thermo-mechanical, and viscoelastic analyses. In parallel, morphological properties such as fiber distribution and dispersion, fiber–matrix adhesion, and fiber exfoliation phenomena were analyzed through a scanning electron microscope (SEM) and energy-dispersive spectroscopy (EDS) to evaluate the relationship between the compounding process, mechanical responses, and morphological parameters. The PLA-based composite exhibited the best results since the Young modulus (+18%), tensile strength (+1.5%), impact (+10%), and creep (+5%) resistance were simultaneously enhanced by the addition of WB fibers, which were well dispersed and distributed in and significantly branched and interlocked with the polymer matrix. PA12- and TPU-based formulations showed a positive behavior (around +47% of the Young modulus and +40% of creep resistance) even if the not-optimal fiber–matrix adhesion and/or the poor de-fibration of WB slightly lowered the tensile strength and elongation at break. Finally, the TPE-based sample exhibited the worst performance because of the poor affinity between hydrophilic WB fibers and the hydrophobic polymer matrix.

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Characterization of a Novel Glycoprotein Isolated from the Basement Membrane Matrix of the Engelbreth-Holm-Swarm Tumor

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)83710-3 ◽

1989 ◽

Vol 264 (9) ◽

pp. 5141-5147

Author(s):

L K Robinson ◽

V A Murrah ◽

M P Moyer ◽

D H Rohrbach

Keyword(s):

Basement Membrane ◽

Membrane Matrix

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Interaction between Galectin-3 and Integrins Mediates Cell-Matrix Adhesion in Endothelial Cells and Mesenchymal Stem Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22105144 ◽

2021 ◽

Vol 22 (10) ◽

pp. 5144

Author(s):

Antonín Sedlář ◽

Martina Trávníčková ◽

Pavla Bojarová ◽

Miluše Vlachová ◽

Kristýna Slámová ◽

...

Keyword(s):

Stem Cells ◽

Endothelial Cells ◽

Cell Adhesion ◽

Vascular Tissue ◽

Cell Functions ◽

Matrix Adhesion ◽

Cell Matrix ◽

Selective Ligand ◽

Galectin 3 ◽

Cell Matrix Adhesion

Galectin-3 (Gal-3) is a β-galactoside-binding protein that influences various cell functions, including cell adhesion. We focused on the role of Gal-3 as an extracellular ligand mediating cell-matrix adhesion. We used human adipose tissue-derived stem cells and human umbilical vein endothelial cells that are promising for vascular tissue engineering. We found that these cells naturally contained Gal-3 on their surface and inside the cells. Moreover, they were able to associate with exogenous Gal-3 added to the culture medium. This association was reduced with a β-galactoside LacdiNAc (GalNAcβ1,4GlcNAc), a selective ligand of Gal-3, which binds to the carbohydrate recognition domain (CRD) in the Gal-3 molecule. This ligand was also able to detach Gal-3 newly associated with cells but not Gal-3 naturally present on cells. In addition, Gal-3 preadsorbed on plastic surfaces acted as an adhesion ligand for both cell types, and the cell adhesion was resistant to blocking with LacdiNAc. This result suggests that the adhesion was mediated by a binding site different from the CRD. The blocking of integrin adhesion receptors on cells with specific antibodies revealed that the cell adhesion to the preadsorbed Gal-3 was mediated, at least partially, by β1 and αV integrins—namely α5β1, αVβ3, and αVβ1 integrins.

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