Surface Immobilized E-Cadherin Mimetic Peptide Regulates the Adhesion and Clustering of Epithelial Cells

Engineering Cellular Self-Adhesions Inside 3D Printed Micro-Arches to Enhance Cell:Biomaterial Attachment

A cell can bind to itself and form a self-adhesion that can be engineered and harnessed as a new way to adhere cells to engineered materials-a key challenge for biomaterials are demonstrated. Here, a 3D structure smaller is developed than a single cell, that a Self-Adhesion-Tunnel (SAT) is called, that causes cells to wrap around it and bind to themselves. This process is driven through the cadherin proteins that regulate cell-cell adhesion, and it is shown that many of the key elements of a normal cell-cell adhesion are found in self-adhesions. Size and shape of the SAT determine the efficiency of self-adhesion formation, and >90% efficient formation of self-adhesions are observed in both kidney and skin cells per SAT. Self-adhesions can persist for at least 24 hrs and act to stabilize the cell-material interface and reduce migration. Overall, this ability to co-opt the native cell-cell adhesion machinery in cells and use it as an attachment strategy can provide new approaches for soft-tissue implant integration and tissue engineering scaffolds where stable tissue-material interfaces are critical.

Cadherin dynamics and cortical tension in remodeling cell-cell adhesion during EMT

Epithelial-to-mesenchymal transition (EMT), a key process in cancer metastasis and fibrosis, disrupts cellular adhesion by replacing epithelial E-cadherin with mesenchymal N-cadherin. While, how the shift from E-cadherin to N-cadherin impacts molecular-scale adhesion mechanics and cluster dynamics-and how these changes weaken adhesion under varying mechanical and environmental conditions-remains poorly understood, limiting our ability to target EMT-driven pathological adhesion dynamics. Here, we developed a unified lattice-clutch model to investigate cadherin clustering, cortical tension, and adhesion strength during EMT. Using atomic force microscopy experiments, we measured the mechanical properties of single cadherin trans-bonds and cadherin-mediated cell-cell and cell-matrix adhesions across varying conditions. Our results demonstrate that N-cadherin trans-bonds are mechanically weaker than E-cadherin trans-bonds, leading to reduced adhesion strength during EMT. Computational modeling and experimental validation further revealed that EMT impairs cadherin clustering and cortical tension regulation, which collectively weaken both cell-cell and cell-matrix adhesions, particularly on stiff substrates. These findings highlight how EMT disrupts adhesion strength at multiple scales-from individual cadherin bonds to collective cluster dynamics. Our study elucidates how EMT-driven changes in cadherin type weaken adhesion strength and mechanotransduction, providing insights into cellular adhesion mechanics and potential therapeutic strategies for targeting EMT-associated diseases such as cancer metastasis and tissue remodeling.

Role of E-cadherin in epithelial barrier dysfunction: implications for bacterial infection, inflammation, and disease pathogenesis

Epithelial barriers serve as critical defense lines against microbial infiltration and maintain tissue homeostasis. E-cadherin, an essential component of adherens junctions, has emerged as a pivotal molecule that secures epithelial homeostasis. Lately, its pleiotropic role beyond barrier function, including its involvement in immune responses, has become more evident. Herein, we delve into the intricate relationship between (dys)regulation of epithelial homeostasis and the versatile functionality of E-cadherin, describing complex mechanisms that underlie barrier integrity and disruption in disease pathogenesis such as bacterial infection and inflammation, among others. Clinical implications of E-cadherin perturbations in host pathophysiology are emphasized; downregulation, proteolytic phenomena, abnormal localization/signaling and aberrant immune reactions are linked with a broad spectrum of pathology beyond infectious diseases. Finally, potential therapeutic interventions that may harness E-cadherin to mitigate barrier-associated tissue damage are explored. Overall, this review highlights the crucial role of E-cadherin in systemic health, offering insights that could pave the way for strategies to reinforce/restore barrier integrity and treat related diseases.

E-cadherin biomaterials reprogram collective cell migration and cell cycling by forcing homeostatic conditions

Cells attach to the world through either cell-extracellular matrix adhesion or cell-cell adhesion, and traditional biomaterials imitate the matrix for integrin-based adhesion. However, materials incorporating cadherin proteins that mimic cell-cell adhesion offer an alternative to program cell behavior and integrate into living tissues. We investigated how cadherin substrates affect collective cell migration and cell cycling in epithelia. Our approach involved biomaterials with matrix proteins on one-half and E-cadherin proteins on the other, forming a "Janus" interface across which we grew a single sheet of cells. Tissue regions over the matrix side exhibited normal collective dynamics, but an abrupt behavior shift occurred across the Janus boundary onto the E-cadherin side, where cells attached to the substrate via E-cadherin adhesions, resulting in stalled migration and slowing of the cell cycle. E-cadherin surfaces disrupted long-range mechanical coordination and nearly doubled the length of the G0/G1 phase of the cell cycle, linked to the lack of integrin focal adhesions on the E-cadherin surface.

Quantum-enhanced diamond molecular tension microscopy for quantifying cellular forces

The constant interplay and information exchange between cells and the microenvironment are essential to their survival and ability to execute biological functions. To date, a few leading technologies such as traction force microscopy, optical/magnetic tweezers, and molecular tension-based fluorescence microscopy are broadly used in measuring cellular forces. However, the considerable limitations, regarding the sensitivity and ambiguities in data interpretation, are hindering our thorough understanding of mechanobiology. Here, we propose an innovative approach, namely, quantum-enhanced diamond molecular tension microscopy (QDMTM), to precisely quantify the integrin-based cell adhesive forces. Specifically, we construct a force-sensing platform by conjugating the magnetic nanotags labeled, force-responsive polymer to the surface of a diamond membrane containing nitrogen-vacancy centers. Notably, the cellular forces will be converted into detectable magnetic variations in QDMTM. After careful validation, we achieved the quantitative cellular force mapping by correlating measurement with the established theoretical model. We anticipate our method can be routinely used in studies like cell-cell or cell-material interactions and mechanotransduction.

E-cadherin biointerfaces reprogram collective cell migration and cell cycling by forcing homeostatic conditions

Cells attach to the world around them in two ways-cell:extracellular-matrix adhesion and cell:cell adhesion-and conventional biomaterials are made to resemble the matrix to encourage integrin-based cell adhesion. However, interest is growing for cell-mimetic interfaces that mimic cell-cell interactions using cadherin proteins, as this offers a new way to program cell behavior and design synthetic implants and objects that can integrate directly into living tissues. Here, we explore how these cadherin-based materials affect collective cell behaviors, focusing specifically on collective migration and cell cycle regulation in cm-scale epithelia. We built culture substrates where half of the culture area was functionalized with matrix proteins and the contiguous half was functionalized with E-cadherin proteins, and we grew large epithelia across this 'Janus' interface. Parts of the tissues in contact with the matrix side of the Janus interface exhibited normal collective dynamics, but an abrupt shift in behaviors happened immediately across the Janus boundary onto the E-cadherin side, where cells formed hybrid E-cadherin junctions with the substrate, migration effectively froze in place, and cell-cycling significantly decreased. E-cadherin materials suppressed long-range mechanical correlations in the tissue and mechanical information reflected off the substrate interface. These effects could not be explained by conventional density, shape index, or contact inhibition explanations. E-cadherin surfaces nearly doubled the length of the G0/G1 phase of the cell cycle, which we ultimately connected to the exclusion of matrix focal adhesions induced by the E-cadherin culture surface.

Sticking together: Harnessing cadherin biology for tissue engineering

Directing cell behavior and building a tissue for therapeutic impact is the main goal of regenerative medicine, for which scientists need to modulate the interaction of cells with biomaterials. The focus of the field thus far has been on the incorporation of cues from the extracellular matrix but we propose that scientists take lessons from cell-cell adhesion proteins, more specifically cadherin biology, as these proteins make multicellularity possible. In this perspective, we re-examine cadherins through the lens of a tissue engineer for the purpose of advancing regenerative medicine. Furthermore, we summarize exciting developments in biomaterials inspired by cadherins and discuss some challenges and opportunities for the future. STATEMENT OF SIGNIFICANCE: Tissue engineers need tools to direct cell behavior. To date, tissue engineers have designed many sophisticated materials to positively influence cell behavior but are faced with the challenge where these materials sometimes work and sometimes fail. This uncertainty is a big unanswered question that challenges the community. We propose that tissue engineering could be more successful if they would take lessons from cell-cell adhesion proteins, more specifically cadherin biology. In the article, we discuss key structural and functional characteristics that make cadherins ideal for tissue engineering approaches. Furthermore, by providing a state-of-the-art overview of exemplary studies that have used cadherins to influence cell behavior, we show tissue engineers that they already have the tools necessary to incorporate this knowledge.

Critical adhesion areas of cells on micro-nanopatterns

Cell adhesion to extracellular matrices (ECM) is critical to physiological and pathological processes as well as biomedical and biotechnological applications. It has been known that a cell can adhere on an adhesive microisland only over a critical size. But no publication has concerned critical adhesion areas of cells on microislands with nanoarray decoration. Herein, we fabricated a series of micro-nanopatterns with different microisland sizes and arginine-glycine-aspartate (RGD) nanospacings on a nonfouling poly(ethylene glycol) background. Besides reproducing that nanospacing of RGD, a ligand of its receptor integrin (a membrane protein), significantly influences specific cell adhesion on bioactive nanoarrays, we confirmed that the concept of critical adhesion area originally suggested in studies of cells on micropatterns was justified also on the micro-nanopatterns, yet the latter exhibited more characteristic behaviors of cell adhesion. We found increased critical adhesion areas of human mesenchymal stem cells (hMSCs) on nanoarrayed microislands with increased RGD nanospacings. However, the numbers of nanodots with respect to the critical adhesion areas were not a constant. A unified interpretation was then put forward after combining nonspecific background adhesion and specific cell adhesion. We further carried out the asymptotic analysis of a series of micro-nanopatterned surfaces to obtain the effective RGD nanospacing on unpatterned free surfaces with densely grafted RGD, which could be estimated nonzero but has never been revealed previously without the assistance of the micro-nanopatterning techniques and the corresponding analysis.

ELECTRONIC SUPPLEMENTARY MATERIAL

Supplementary materials and methods (details of fabrication of micro-nanopatterns), and supplementary results (selective adhesion or localization of hMSCs on nanoarrayed microislands with non-fouling background, calculation of critical number of integrin-ligand binding N*, etc.) are available in the online version of this article at 10.1007/s12274-021-3711-6.

Bioengineering strategies to control epithelial-to-mesenchymal transition for studies of cardiac development and disease

Epithelial-to-mesenchymal transition (EMT) is a process that occurs in a wide range of tissues and environments, in response to numerous factors and conditions, and plays a critical role in development, disease, and regeneration. The process involves epithelia transitioning into a mobile state and becoming mesenchymal cells. The investigation of EMT processes has been important for understanding developmental biology and disease progression, enabling the advancement of treatment approaches for a variety of disorders such as cancer and myocardial infarction. More recently, tissue engineering efforts have also recognized the importance of controlling the EMT process. In this review, we provide an overview of the EMT process and the signaling pathways and factors that control it, followed by a discussion of bioengineering strategies to control EMT. Important biological, biomaterial, biochemical, and physical factors and properties that have been utilized to control EMT are described, as well as the studies that have investigated the modulation of EMT in tissue engineering and regenerative approaches in vivo, with a specific focus on the heart. Novel tools that can be used to characterize and assess EMT are discussed and finally, we close with a perspective on new bioengineering methods that have the potential to transform our ability to control EMT, ultimately leading to new therapies.

Ultrasound-targeted microbubble destruction augmented synergistic therapy of rheumatoid arthritis via targeted liposomes

Rheumatoid arthritis (RA) can lead to joint destruction and deformity, which is a significant cause of the loss of the young and middle-aged labor force. However, the treatment of RA is still filled with challenges. Though dexamethasone, one of the glucocorticoids, is commonly used in the treatment of RA, its clinical use is limited because of the required high-dose and long-term use, unsatisfactory therapeutic effects, and various side-effects. Ultrasound-targeted microbubble destruction (UTMD) can augment the ultrasonic cavitation effects and trigger drug release from targeted nanocarriers in the synovial cavity, which makes it a more effective synergistic treatment strategy for RA. In this work, we aim to utilize the UTMD effect to augment the synergistic therapy of RA by using polyethylene glycol (PEG)-modified folate (FA)-conjugated liposomes (LPs) loaded with dexamethasone sodium phosphate (DexSP) (DexSP@LPs-PEG-FA). The UTMD-mediated DexSP@LPs-PEG-FA for targeted delivery of DexSP including a synergistic ultrasonic cavitation effect and drug therapy were investigated through in vitro RAW264.7 cell experiments and in vivo collagen-induced arthritis SD rat model animal experiments. The results show the DexSP release from targeted liposomes was improved under the UTMD effect. Likewise, the folate-conjugated liposomes displayed targeting association to RAW264.7 cells. Together with the application of ultrasound and microbubbles, liposomes-delivered DexSP potently reduced joints swelling, bone erosion, and inflammation in both joints and serum with a low dose. These results demonstrated that UTMD-mediated folate-conjugated liposomes are not only a promising method for targeted synergistic treatment of RA but also may show high potential for serving as nanomedicines for many other biomedical fields.

You Talking to Me? Cadherin and Integrin Crosstalk in Biomaterial Design

While much work has been done in the design of biomaterials to control integrin-mediated adhesion, less emphasis has been put on functionalization of materials with cadherin ligands. Yet, cell-cell contacts in combination with cell-matrix interactions are key in driving embryonic development, collective cell migration, epithelial to mesenchymal transition, and cancer metastatic processes, among others. This review focuses on the incorporation of both cadherin and integrin ligands in biomaterial design, to promote what is called the "adhesive crosstalk." First, the structure and function of cadherins and their role in eliciting mechanotransductive processes, by themselves or in combination with integrin mechanosensing, are introduced. Then, biomaterials that mimic cell-cell interactions, and recent applications to get insights in fundamental biology and tissue engineering, are critically discussed.

Controllable ligand spacing stimulates cellular mechanotransduction and promotes stem cell osteogenic differentiation on soft hydrogels

Hydrogels with tunable mechanical properties have provided a tremendous opportunity to regulate stem cell differentiation. Hydrogels with osteoid (about 30-40 kPa) or higher stiffness are usually required to induce the osteogenic differentiation of mesenchymal stem cells (MSCs). It is yet difficult to achieve the same differentiation on very soft hydrogels, because of low environmental mechanical stimuli and restricted cellular mechanotransduction. Here, we modulate cellular spatial sensing of integrin-adhesive ligands via quasi-hexagonally arranged nanopatterns to promote cell mechanosensing on hydrogels having low stiffness (about 3 kPa). The increased interligand spacing has been shown to regulate actomyosin force loading to recruit extra integrins on soft hydrogels. It therefore activates mechanotransduction and promotes the osteogenic differentiation of MSCs on soft hydrogels to the level comparable with the one observed on osteoid stiffness. Our work opens up new possibilities for the design of biomaterials and tissue scaffolds for regenerative therapeutics.

Advancing Cell-Instructive Biomaterials Through Increased Understanding of Cell Receptor Spacing and Material Surface Functionalization

Abstract

Regenerative medicine is aimed at restoring normal tissue function and can benefit from the application of tissue engineering and nano-therapeutics. In order for regenerative therapies to be effective, the spatiotemporal integration of tissue-engineered scaffolds by the native tissue, and the binding/release of therapeutic payloads by nano-materials, must be tightly controlled at the nanoscale in order to direct cell fate. However, due to a lack of insight regarding cell–material interactions at the nanoscale and subsequent downstream signaling, the clinical translation of regenerative therapies is limited due to poor material integration, rapid clearance, and complications such as graft-versus-host disease. This review paper is intended to outline our current understanding of cell–material interactions with the aim of highlighting potential areas for knowledge advancement or application in the field of regenerative medicine. This is achieved by reviewing the nanoscale organization of key cell surface receptors, the current techniques used to control the presentation of cell-interactive molecules on material surfaces, and the most advanced techniques for characterizing the interactions that occur between cell surface receptors and materials intended for use in regenerative medicine.

Lay Summary

The combination of biology, chemistry, materials science, and imaging technology affords exciting opportunities to better diagnose and treat a wide range of diseases. Recent advances in imaging technologies have enabled better understanding of the specific interactions that occur between human cells and their immediate surroundings in both health and disease. This biological understanding can be used to design smart therapies and tissue replacements that better mimic native tissue. Here, we discuss the advances in molecular biology and technologies that can be employed to functionalize materials and characterize their interaction with biological entities to facilitate the design of more sophisticated medical therapies.

Synergistic Effect of Cell-Derived Extracellular Matrices and Topography on Osteogenesis of Mesenchymal Stem Cells

Cell-derived matrices (CDMs) are an interesting alternative to conventional sources of extracellular matrices (ECMs) as CDMs mimic the natural ECM composition better and are therefore attractive as a scaffolding material for regulating the functions of stem cells. Previous research on stem cell differentiation has demonstrated that both surface topography and CDMs have a significant influence. However, not much focus has been devoted to elucidating possible synergistic effects of CDMs and topography on osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBM-MSCs). In this study, polydimethylsiloxane (PDMS)-based anisotropic topographies (wrinkles) with various topography dimensions were prepared and subsequently combined with native ECMs produced by human fibroblasts that remained on the surface topography after decellularization. The synergistic effect of CDMs combined with topography on osteogenic differentiation of hBM-MSCs was investigated. The results showed that substrates with specific topography dimensions, coated with aligned CDMs, dramatically enhanced the capacity of osteogenesis as investigated using immunofluorescence staining for identifying osteopontin (OPN) and mineralization. Furthermore, the hBM-MSCs on the substrates decorated with CDMs exhibited a higher percentage of (Yes-associated protein) YAP inside the nucleus, stronger cell contractility, and greater formation of focal adhesions, illustrating that enhanced osteogenesis is partly mediated by cellular tension and mechanotransduction following the YAP pathway. Taken together, our findings highlight the importance of ECMs mediating the osteogenic differentiation of stem cells, and the combination of CDMs and topography will be a powerful approach for material-driven osteogenesis.

Expression profile-based screening for critical genes reveals S100A4, ACKR3 and CDH1 in docetaxel-resistant prostate cancer cells

Docetaxel is a first-line anticancer drug widely used in the treatment of advanced prostate cancer. However, its therapeutic efficacy is limited by its side effects and the development of chemoresistance by the tumor. Using a gene differential expression microarray, we identified 449 genes differentially expressed in docetaxel-resistant DU145 and PC3 cell lines as compared to docetaxel-sensitive controls. Moreover, western blotting and immunohistochemistry revealed altered expression of S100A4, ACKR3 and CDH1in clinical tumor samples. Cytoscape software was used to investigate the relationship between critical proteins and their signaling transduction networks. Functional and pathway enrichment analyses revealed that these signaling pathways were closely related to cellular proliferation, cell adhesion, cell migration and metastasis. In addition, ACKR3 knockout using the crispr/cas9 method andS100A4knockdownusing targeted shRNA exerted additive effects suppressing cancer cell proliferation and migration. This exploratory analysis provides information about potential candidate genes. It also provides new insight into the molecular mechanism underlying docetaxel-resistance in androgen-independent prostate cancer and highlights potential targets to improve therapeutic outcomes.

Cadherin Signaling in Cancer: Its Functions and Role as a Therapeutic Target

Cadherin family includes lists of transmembrane glycoproteins which mediate calcium-dependent cell-cell adhesion. Cadherin-mediated adhesion regulates cell growth and differentiation throughout life. Through the establishment of the cadherin-catenin complex, cadherins provide normal cell-cell adhesion and maintain homeostatic tissue architecture. In the process of cell recognition and adhesion, cadherins act as vital participators. As results, the disruption of cadherin signaling has significant implications on tumor formation and progression. Altered cadherin expression plays a vital role in tumorigenesis, tumor progression, angiogenesis, and tumor immune response. Based on ongoing research into the role of cadherin signaling in malignant tumors, cadherins are now being considered as potential targets for cancer therapies. This review will demonstrate the mechanisms of cadherin involvement in tumor progression, and consider the clinical significance of cadherins as therapeutic targets.

Materials Stiffness-Dependent Redox Metabolic Reprogramming of Mesenchymal Stem Cells for Secretome-Based Therapeutic Angiogenesis

Cellular redox metabolism has emerged as a key tenet in stem cell biology that can profoundly influence the paracrine activity and therapeutic efficacy of mesenchymal stem cells (MSCs). Although the use of materials cues to direct the differentiation of MSCs has been widely investigated, little is known regarding the role of materials in the control of redox paracrine signaling in MSCs. Herein, using a series of mechanically tunable fibronectin-conjugated polyacrylamide (FN-PAAm) hydrogel substrates, it is shown that a mechanically compliant microenvironment with native-tissue mimicking stiffness (E = 0.15 kPa) can mechano-regulate the intracellular reactive oxygen species (ROS) level in human adipose-derived MSCs (ADMSCs). The cells reciprocate to the ROS imbalance by co-activating the nuclear factor erythroid 2-related factor 2 and hypoxia-inducible factor 1 alpha stress response signaling pathways to increase the production of vascular endothelial growth factor and basic fibroblast growth factor. Conditioned medium collected from ADMSCs grown on the 0.15 kPa FN-PAAm is found to significantly promote in vitro and ex ovo vascularization events. Collectively, these findings highlight the importance of delineating critical materials properties that can enable the reprogramming of cellular redox signaling for advanced MSCs-based secretome regenerative medicine.