Fluorescent resonance energy transfer: A tool for probing molecular cell–biomaterial interactions in three dimensions

Abstract

The current paradigm in designing biomaterials is to optimize material chemical and physical parameters based on correlations between these parameters and downstream biological responses, whether in vitro or in vivo. Extensive developments in molecular design of biomaterials have facilitated identification of several biophysical and biochemical variables (e.g. adhesion peptide density, substrate elastic modulus) as being critical to cell response. However, these empirical observations do not indicate whether different parameters elicit cell responses by modulating redundant variables of the cell-material interface (e.g. number of cell-material bonds, cell-matrix mechanics). Recently, fluorescence resonance energy transfer (FRET) has been applied to quantitatively analyze parameters of the cell-material interface for both two- and three-dimensional adhesion substrates. Tools based on FRET have been utilized to quantify several parameters of the cell-material interface relevant to cell response, including molecular changes in matrix proteins induced by interactions both with surfaces and cells, the number of bonds between integrins and their adhesion ligands, and changes in the crosslink density of hydrogel synthetic extracellular matrix analogs. As such techniques allow both dynamic and 3-D analyses they will be useful to quantitatively relate downstream cellular responses (e.g. gene expression) to the composition of this interface. Such understanding will allow bioengineers to fully exploit the potential of biomaterials engineered on the molecular scale, by optimizing material chemical and physical properties to a measurable set of interfacial parameters known to elicit a predictable response in a specific cell population. This will facilitate the rational design of complex, multi-functional biomaterials used as model systems for studying diseases or for clinical applications.

Zwitterionic Chitosan Derivatives for pH-Sensitive Stealth Coating

“…To determine the interactions among DP complex, SALM-CS, and BSA using FRET, we labeled them with fluorescence dyes, FPG-456 (λ abs /λ em = 495/526 nm), FPR-553 (λ abs /λ em = 553/587 nm), and FPR-648 (λ abs /λ em = 647/672 nm), to form DP-456, SALM-CS-553, BSA-553, and BSA-648. The FRET phenomenon occurs only when the distance between donor and receptor fluorophores is <10 nm . Here the FRET pairs are FPG-456 and FPR-553 and FPR-553 and FPR-648.…”

Zwitterionic Chitosan Derivatives for pH-Sensitive Stealth Coating

“…To determine the interactions among DP complex, SALM-CS, and BSA using FRET, we labeled them with fluorescence dyes, FPG-456 (λ abs /λ em = 495/526 nm), FPR-553 (λ abs /λ em = 553/587 nm), and FPR-648 (λ abs /λ em = 647/672 nm), to form DP-456, SALM-CS-553, BSA-553, and BSA-648. The FRET phenomenon occurs only when the distance between donor and receptor fluorophores is <10 nm . Here the FRET pairs are FPG-456 and FPR-553 and FPR-553 and FPR-648.…”

Fluorescent Probes with Förster Resonance Energy Transfer Function for Monitoring the Gelation and Formation of Nanoparticles Based on Chitosan Copolymers

“…FRET is a mechanism of energy transfer between two chromophores (from donor to acceptor), which occurs without intermediate photon emission and is the result of the dipole–dipole interaction between the donor and acceptor [ 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. FRET was effectively used to monitor gelation, since the implementation of FRET requires a spatial arrangement of fluorophores less than 10 Å, which can be realized, for example, in a hydrophobic core of micelles or in a tangle of polymers upon gelation.…”

Plasmonic Biosensing for Label-Free Detection of Two Hallmarks of Cancer Cells: Cell-Matrix Interaction and Cell Division

“…Thus, the composition and density of adhesion receptors on the cell surface, as well as the strength of receptor-ligand bonds and the type of ECM present, may lead to different adhesion dynamics. Moreover, adhesion dynamics involve changes in the cellular traction forces, generated during rearrangement of ECM ligands, in the process of forming stable cell–substrate adhesion contacts [ 30 ]. In line with this, here we used fibronectin as the ECM protein, and differences in the expression of fibronectin receptors have been described among colorectal cancer cell lines [ 51 , 52 ].…”

Zwitterionic Chitosan Derivatives for pH-Sensitive Stealth Coating

“…To determine the interactions among DP complex, SALM-CS, and BSA using FRET, we labeled them with fluorescence dyes, FPG-456 (λ abs /λ em = 495/526 nm), FPR-553 (λ abs /λ em = 553/587 nm), and FPR-648 (λ abs /λ em = 647/672 nm), to form DP-456, SALM-CS-553, BSA-553, and BSA-648. The FRET phenomenon occurs only when the distance between donor and receptor fluorophores is <10 nm . Here the FRET pairs are FPG-456 and FPR-553 and FPR-553 and FPR-648.…”

Fluorescent Probes with Förster Resonance Energy Transfer Function for Monitoring the Gelation and Formation of Nanoparticles Based on Chitosan Copolymers

“…FRET is a mechanism of energy transfer between two chromophores (from donor to acceptor), which occurs without intermediate photon emission and is the result of the dipole–dipole interaction between the donor and acceptor [ 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. FRET was effectively used to monitor gelation, since the implementation of FRET requires a spatial arrangement of fluorophores less than 10 Å, which can be realized, for example, in a hydrophobic core of micelles or in a tangle of polymers upon gelation.…”

Plasmonic Biosensing for Label-Free Detection of Two Hallmarks of Cancer Cells: Cell-Matrix Interaction and Cell Division

“…Thus, the composition and density of adhesion receptors on the cell surface, as well as the strength of receptor-ligand bonds and the type of ECM present, may lead to different adhesion dynamics. Moreover, adhesion dynamics involve changes in the cellular traction forces, generated during rearrangement of ECM ligands, in the process of forming stable cell–substrate adhesion contacts [ 30 ]. In line with this, here we used fibronectin as the ECM protein, and differences in the expression of fibronectin receptors have been described among colorectal cancer cell lines [ 51 , 52 ].…”

Zwitterionic Chitosan Derivatives for pH-Sensitive Stealth Coating

“…To determine the interactions among DP complex, SALM-CS, and BSA using FRET, we labeled them with fluorescence dyes, FPG-456 (λ abs /λ em = 495/526 nm), FPR-553 (λ abs /λ em = 553/587 nm), and FPR-648 (λ abs /λ em = 647/672 nm), to form DP-456, SALM-CS-553, BSA-553, and BSA-648. The FRET phenomenon occurs only when the distance between donor and receptor fluorophores is <10 nm . Here the FRET pairs are FPG-456 and FPR-553 and FPR-553 and FPR-648.…”

Fluorescent Probes with Förster Resonance Energy Transfer Function for Monitoring the Gelation and Formation of Nanoparticles Based on Chitosan Copolymers

“…FRET is a mechanism of energy transfer between two chromophores (from donor to acceptor), which occurs without intermediate photon emission and is the result of the dipole–dipole interaction between the donor and acceptor [ 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. FRET was effectively used to monitor gelation, since the implementation of FRET requires a spatial arrangement of fluorophores less than 10 Å, which can be realized, for example, in a hydrophobic core of micelles or in a tangle of polymers upon gelation.…”

Plasmonic Biosensing for Label-Free Detection of Two Hallmarks of Cancer Cells: Cell-Matrix Interaction and Cell Division

“…Thus, the composition and density of adhesion receptors on the cell surface, as well as the strength of receptor-ligand bonds and the type of ECM present, may lead to different adhesion dynamics. Moreover, adhesion dynamics involve changes in the cellular traction forces, generated during rearrangement of ECM ligands, in the process of forming stable cell–substrate adhesion contacts [ 30 ]. In line with this, here we used fibronectin as the ECM protein, and differences in the expression of fibronectin receptors have been described among colorectal cancer cell lines [ 51 , 52 ].…”