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Recently, a variety of microenvironmental biophysical stimuli have been proved to play a crucial role in regulating cell functions. Among them, morpho-physical cues, like curvature, are emerging as key regulators of cellular behavior. Changes in substrate curvature have been shown to impact the arrangement of Focal Adhesions (FAs), influencing the direction and intensity of cytoskeleton generated forces and resulting in an overall alteration of cell mechanical identity. In their native environment, cells encounter varying degrees of substrate curvature, and in specific organs, they are exposed to dynamic changes of curvature due to periodic tissue deformation. However, the mechanism by which cells perceive substrate curvature remains poorly understood. To this aim, a micro-pneumatic device was designed and implemented. This device enables the controlled application of substrate curvature, both statically and dynamically. Employing a combined experimental and simulative approach, human adipose-derived stem cells were exposed to controlled curvature intensity and frequency. During this exposure, measurements were taken on FAs extension and orientation, cytoskeleton organization and cellular/nuclear alignment. The data clearly indicated a significant influence of the substrate curvature on cell adhesion processes. These findings contribute to a better understanding of the mechanisms through which cells perceive and respond to substrate curvature signals. This work is our contribution to the comprehension of substrate curvature's function as a crucial regulator of cell adhesion at the scale of focal adhesions and cell mechanical identity. In recent years, a large body of knowledge is continuously growing providing comprehension of the role of various microenvironmental biophysical stimuli in regulating cell functions. Nevertheless, little is known about the role of substrate curvature, in particular, when cells are exposed to this stimulus in a dynamic manner. To address the role of substrate curvature on cellular behavior, a micro-pneumatic device was designed and implemented. This device enables the controlled application of substrate curvature, both statically and dynamically. The experiment data made it abundantly evident that the substrate curvature had a major impact on the mechanisms involved in cell adhesion. [Display omitted] [ABSTRACT FROM AUTHOR]

Bioresorbable shape memory polymers (SMP) are an emerging class of polymers that can help address several challenges associated with minimally invasive surgery by providing a solution for structural tissue repair. Like most synthetic polymer networks, SMPs require additional biorelevance and modification for biomedical applications. Methodologies used to incorporate bioactive ligands must preserve SMP thermomechanics and ensure biofunctionality following in vivo delivery. We have previously described the development of a novel thermoresponsive bioresorbable SMP, poly (glycerol dodecanedioate) (PGD). In this study, cell-adhesive peptide sequences RGD and YIGSR were conjugated with PGD. We investigated 1) the impact of conjugated peptides on the fixity (R f), recovery (R r), and recovery rate (dR r /dT), 2) the impact of conjugated peptides on cell binding, and 3) the impact of the shape memory cycle (T prog) on conjugated peptide functionality towards binding human bone marrow stromal cells (BMSC). Peptide conjugation conditions impact fixity but not the recovery or recovery rate (p < 0.01). Peptide-conjugated substrates increased cell attachment and proliferation compared with controls (p < 0.001). Using complementary integrin binding cell-adhesive peptides increased proliferation compared with using single peptides (p < 0.05). Peptides bound to PGD substrates exhibited specificity to their respective integrin targets. Following the shape memory cycle, peptides maintained functionality and specificity depending on the shape memory cycle conditions (p < 0.001). The dissipation of strain energy during recovery can drive differential arrangement of conjugated sequences impacting functionality, an important design consideration for functionalized SMPs. Shape memory elastomers are an emerging class of polymers that are well-suited for minimally invasive repair of soft tissues. Tissue engineering approaches commonly utilize biodegradable scaffolds to deliver instructive cues, including cells and bioactive signals. Delivering these instructive cues on biodegradable shape memory elastomers requires modification with bioactive ligands. Furthermore, it is necessary to ensure the specificity of the ligands to their biological targets when conjugated to the polymer. Moreover, the bioactive ligand functionality must be conserved after completing the shape memory cycle, for applications in tissue engineering. [Display omitted] [ABSTRACT FROM AUTHOR]

Monocytes, the circulating macrophage precursors, contribute to diseases like atherosclerosis and asthma. Long non-coding RNAs (lncRNAs) have been shown to modulate the phenotype and inflammatory capacity of monocytes. We previously discovered the lncRNA SMANTIS, which contributes to cellular phenotype expression by controlling BRG1 in mesenchymal cells. Here, we report that SMANTIS is particularly highly expressed in monocytes and lost during differentiation into macrophages. Moreover, different types of myeloid leukemia presented specific SMANTIS expression patterns. Interaction studies revealed that SMANTIS binds RUNX1, a transcription factor frequently mutated in AML, primarily through its Alu-element on the RUNT domain. RNA-seq after CRISPR/Cas9-mediated deletion of SMANTIS or RUNX1 revealed an association with cell adhesion and both limited the monocyte adhesion to endothelial cells. Mechanistically, SMANTIS KO reduced RUNX1 genomic binding and altered the interaction of RUNX1 with EP300 and CBFB. Collectively, SMANTIS interacts with RUNX1 and attenuates monocyte adhesion, which might limit monocyte vascular egress. The long non-coding RNA SMANTIS interacts with the transcription factor RUNX1 in an Alu-RUNT-dependent manner in monocytes and limits monocyte adhesion to endothelial cells. [ABSTRACT FROM AUTHOR]

1. Salmonella Gallinarum strains isolated from a southern Brazil fowl typhoid outbreak were subjected to phenotypic and genotypic analyses to identify genetic elements that could improve prevention and control strategies.2. Whole-genome sequencing revealed the presence of the aac(6’)-Iaa gene, conferring aminoglycoside resistance, along with novel chromosomal point mutations, including the first detection of parE p.S451F in Salmonella Gallinarum.3. Additionally, IncFII(S) plasmid replicons, Salmonella pathogenicity islands and 105 virulence genes associated with cell adhesion, invasion and antimicrobial peptide resistance were identified.4. These findings shed light on the molecular mechanisms of fowl typhoid and provide crucial insights into emerging antimicrobial resistance and virulence factors. [ABSTRACT FROM AUTHOR]

This review provides a personal overview of significant scientific developments in the thrombospondin field during the course of my career. Thrombospondins are multidomain, multimeric, calcium‐binding extracellular glycoproteins with context‐specific roles in tissue organisation. They act at cell surfaces and within ECM to regulate cell phenotype and signalling, differentiation and assembly of collagenous ECM, along with tissue‐specific roles in cartilage, angiogenesis and synaptic function. More recently, intracellular, homeostatic roles have also been identified. Resolution of structures for the major domains of mammalian thrombospondins has facilitated major advances in understanding thrombospondin biology from molecule to tissue; for example, in illuminating molecular consequences of disease‐causing coding mutations in human pseudoachrondroplasia. Although principally studied in vertebrates, thrombospondins are amongst the most ancient of animal ECM proteins, with many invertebrates encoding a single thrombospondin and the thrombospondin gene family of vertebrates originating through gene duplications. Moreover, thrombospondins form one branch of a thrombospondin superfamily that debuted at the origin of metazoans. The super‐family includes additional sub‐groups, present only in invertebrates, that differ in N‐terminal domain organisation, share the distinctive TSP C‐terminal region domain architecture and, to the limited extent studied to date, apparently contribute to tissue development and organisation. Finally, major lines of translational research are discussed, related to fibrosis; TSP1, TSP2 and inhibition of angiogenesis; and the alleviation of chronic cartilage tissue pathologies in pseudoachrondroplasia. [ABSTRACT FROM AUTHOR]

The repair and regeneration of cartilage is a challenge for scientists and clinical surgery. Achieving cell adhesion and regeneration, anti‐inflammatory, lubrication, targeted drug delivery and controlled release simultaneously in cartilage treatment are the goals of researchers. Polymer composites and hybrids have the potential to realize above functions in cartilage tissue engineering. This review refers to cartilage injuries, current clinical techniques, and their benefits and limitations, focusing on the most relevant and state of art of advanced polymers for cartilage tissue engineering. The frontier applications of multifunctional polymer composites and hybrids in cartilage tissue engineering are discussed in depth, including polymer scaffold, polymer bio‐lubricant, and zwitterionic polymer for drug delivery and sustained drug release. A summary of comprehensive properties of polymers such as processability, mechanical properties, biocompatibility, biodegradability, hydrophilicity, cytotoxicity, etc., and their mechanisms are analyzed. Furthermore, some key challenges and outstanding concerns on polymer‐based materials for cartilage tissue engineering are presented followed by future perspectives. Highlights: The state of art of advanced polymers for cartilage tissue engineering.The advanced bionic property and mechanism of polymer composites and hybrids.Polymers for scaffold, biolubricant, drug delivery, sustained drug release.Future perspectives on polymer composites, hybrids‐based cartilage materials. [ABSTRACT FROM AUTHOR]

Combining phytochemicals and nanotechnology to improve the unfavorable innate properties of phytochemicals and develop them into potent nanomedicines to enhance antitumor efficacy has become a novel strategy for cancer chemoprevention. Melanoma is the most aggressive, metastatic, and deadly disease of the primary cutaneous neoplasms. In this study, we fabricated phytoconstituent-derived zingerone nanoparticles (NPs) and validated their effects on cell adhesion and motility in melanoma B16F10 cells. Our data indicated that zingerone NPs significantly induced cytotoxicity and anti-colony formation and inhibited cell migration and invasion. Moreover, zingerone NPs dramatically interfered with the cytoskeletal reorganization and markedly delayed the period of cell adhesion. Our results also revealed that zingerone NPs-mediated downregulation of MMPs (matrix metalloproteinases) activity is associated with inhibiting cell adhesion and motility. We further evaluated the effects of zingerone NPs on Src/FAK /Paxillin signaling, our data showed that zingerone NPs significantly inhibited the protein activities of Src, FAK, and Paxillin, indicating that they play important roles in zingerone NP-mediated anti-motility and anti-invasion in melanoma cells. Accordingly, the phytoconstituent-zingerone NPs can strengthen the inhibition of tumor growth, invasion, and metastasis in malignant melanoma. Altogether, these multi-pharmacological benefits of zingerone NPs will effectively achieve the purpose of melanoma prevention and invasion inhibition. [Display omitted] • Nanosizing ginger phytoconstituent zingerone possesses superior anti-tumorigenesis. • Zingerone NPs promoted cytotoxicity and anti-cell adhesion in melanoma cells. • Zingerone NPs-mediated downregulation of cell invasion and MMPs activity. • Src/FAK/Paxillin signaling is involved in zingerone NP-mediated anti-cell motility. [ABSTRACT FROM AUTHOR]

Background: Endogenous insulin supplementation is essential for individuals with type 1 diabetes (T1D). However, current treatments, including pancreas transplantation, insulin injections, and oral medications, have significant limitations. The development of engineered cells that can secrete endogenous insulin offers a promising new therapeutic strategy for type 1 diabetes (T1D). This approach could potentially circumvent autoimmune responses associated with the transplantation of differentiated b-cells or systemic delivery of viral vectors. Methods: We utilized CRISPR/Cas9 gene editing coupled with homologydirected repair (HDR) to precisely integrate a promoter-free EMCVIRES-insulin cassette into the 3' untranslated region (UTR) of the GAPDH gene in human HEK-293T cells. Subsequently quantified insulin expression levels in these engineered cells, the viability and functionality of the engineered cells when seeded on different cell vectors (GelMA and Cytopore I) were also assessed. Finally, we investigated the therapeutic potential of EMCVIRES-based insulin secretion circuits in reversing Hyperglycaemia in T1D mice. Result: Our results demonstrate that HDR-mediated gene editing successfully integrated the IRES-insulin loop into the genome of HEK-293T cells, a nonendocrine cell line, enabling the expression of human-derived insulin. Furthermore, Cytopore I microcarriers facilitated cell attachment and proliferation during in vitro culture and enhanced cell survival posttransplantation. Transplantation of these cell-laden microcarriers into mice led to the development of a stable, fat-encapsulated structure. This structure exhibited the expression of the platelet-endothelial cell adhesion molecule CD31, and no significant immune rejection was observed throughout the experiment. Diabetic mice that received the cell carriers reversed hyperglycemia, and blood glucose fluctuations under simulated feeding stimuli were very similar to those of healthy mice. Conclusion: In summary, our study demonstrates that Cytopore I microcarriers are biocompatible and promote long-term cell survival in vivo. The promoterfree EMCVIRES-insulin loop enables non-endocrine cells to secrete mature insulin, leading to a rapid reduction in glucose levels. We have presented a novel promoter-free genetic engineering strategy for insulin secretion and proposed an efficient cell transplantation method. Our findings suggest the potential to expand the range of cell sources available for the treatment of diabetes, offering new avenues for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Background: Type VI secretion system (T6SS) is widely present in Gram-negative bacteria and directly mediates antagonistic prokaryote interactions. PAAR (proline-alanine-alanine-arginine repeats) proteins have been proven essential for T6SS-mediated secretion and target cell killing. Although PAAR proteins are commonly found in A. baumannii, their biological functions are not fully disclosed yet. In this study, we investigated the functions of a PAAR protein termed TagP (T6SS-associated-gene PAAR), encoded by the gene ACX60_RS09070 outside the core T6SS locus of A. baumannii strain ATCC 17978. Methods: In this study, tagP null and complement A. baumannii ATCC 17978 strains were constructed. The influence of TagP on T6SS function was investigated through Hcp detection and bacterial competition assay; the influence on environmental fitness was studied through in vitro growth, biofilm formation assay, surface motility assay, survivability in various simulated environmental conditions; the influence on pathogenicity was explored through cell adhesion and invasion assays, intramacrophage survival assay, serum survival assay, and G. melonella Killing assays. Quantitative transcriptomic and proteomic analyses were utilized to observe the global impact of TagP on bacterial status. Results: Compared with the wildtype strain, the tagP null mutant was impaired in several tested phenotypes such as surface motility, biofilm formation, tolerance to adverse environments, adherence to eukaryotic cells, endurance to serum complement killing, and virulence to Galleria melonella. Notably, although RNASeq and proteomics analysis revealed that many genes were significantly downregulated in the tagP null mutant compared to the wildtype strain, there is no significant difference in their antagonistic abilities. We also found that Histonelike nucleoid structuring protein (H-NS) was significantly upregulated in the tagP null mutant at both mRNA and protein levels. Conclusions: This study enriches our understanding of the biofunction of PAAR proteins in A. baumannii. The results indicates that TagP involved in a unique modulation of fitness and virulence control in A. baumannii, it is more than a classic PAAR protein involved in T6SS, while how TagP play roles in the fitness and virulence of A. baumannii needs further investigation to clarify. [ABSTRACT FROM AUTHOR]

Background: Neural cell-electrode coupling is crucial for effective neural and retinal prostheses. Enhancing this coupling can be achieved through surface modification and geometrical design to increase neuron-electrode proximity. In the current research, we focused on designing and studying various biomolecules as a method to elicit neural cell-electrode adhesion via cellspecific integrin mechanisms. Methods: We designed extracellular matrix biomimetic molecules with different head sequences (RGD or YIGSR), structures (linear or cyclic), and spacer lengths (short or long). These molecules, anchored by a thiol (SH) group, were deposited onto gold surfaces at various concentrations. We assessed the modifications using contact angle measurements, fluorescence imaging, and X-ray Photoelectron Spectroscopy (XPS). We then analyzed the adhesion of retinal cells and HEK293 cells to the modified surfaces by measuring cell density, surface area, and focal adhesion spots, and examined changes in adhesion-related gene and integrin expression. Results: Results showed that YIGSR biomolecules significantly enhanced retinal cell adhesion, regardless of spacer length. For HEK293 cells, RGD biomolecules were more effective, especially with cyclic RGD and long spacers. Both cell types showed increased expression of specific adhesion integrins and proteins like vinculin and PTK2; these results were in agreement with the adhesion studies, confirming the cell-specific interactions with modified surfaces. Conclusion: This study highlights the importance of tailored biomolecules for improving neural cell adhesion to electrodes. By customizing biomolecules to foster specific and effective interactions with adhesion integrins, our study provides valuable insights for enhancing the integration and functionality of retinal prostheses and other neural implants. [ABSTRACT FROM AUTHOR]

Nine quinoline‐1,2,4‐triazine hybrids (5 a–5 i) were designed, synthesized, and subjected to evaluation as potential anti‐cancer agents. Structures validation of the synthesized analogues was accomplished through comprehensive analysis employing NMR, HRMS, and IR spectroscopy techniques. Furthermore, the molecular structures of compounds 5 a, 5 d and 5 h were authenticated via single crystal X‐ray diffraction. In an extensive screening process against the human pancreatic cancer PANC‐1 cell line utilizing the MTT assay, all quinoline‐1,2,4‐triazine hybrids (5 a–5 i) manifested significant anti‐proliferative activity. Compound 5 g demonstrated a significant anti‐proliferative effect with an IC50 value of 26.8 μM, similar to the positive control, 5‐Fu. Subsequent investigations revealed varying degrees of cell viability in MDA‐MB‐231, A549, and UM‐UC‐3 cell lines upon exposure to different concentrations of compound 5 g. These findings lead us to postulate that compound 5 g may impede the migration, invasion, and adhesion of PANC‐1 cells, similar to the effects observed with 5‐Fu. [ABSTRACT FROM AUTHOR]

Inflammatory bowel disease (IBD) represents a group of recurrent chronic inflammatory disorders associated with autoimmune dysregulation, typically characterized by neutrophil infiltration and mucosal inflammatory lesions. Neutrophils, as the earliest immune cells to arrive at inflamed tissues, play a dual role in the onset and progression of mucosal inflammation in IBD. Most of these cells specifically express CD177, a molecule increasingly recognized for its critical role in the pathogenesis of IBD. Under IBD-related inflammatory stimuli, CD177 is highly expressed on neutrophils and promotes their migration. CD177 + neutrophils activate bactericidal and barrier-protective functions at IBD mucosal inflammation sites and regulate the release of inflammatory mediators highly correlated with the severity of inflammation in IBD patients, thus playing a dual role. However, mitigating the detrimental effects of neutrophils in inflammatory bowel disease remains a challenge. Based on these data, we have summarized recent articles on the role of neutrophils in intestinal inflammation, with a particular emphasis on CD177, which mediates the recruitment, transepithelial migration, and activation of neutrophils, as well as their functional consequences. A better understanding of CD177 + neutrophils may contribute to the development of novel therapeutic targets to selectively modulate the protective role of this class of cells in IBD. [ABSTRACT FROM AUTHOR]

Zinc (Zn) is gaining increased recognition as a biodegradable metal in biomedical applications but clinical translation is limited due to its poor biocompatibility. This study addresses these issues through an innovative biomimetic strategy, introducing an efficient surface nanoengineering approach that creates nano‐geometric features and chemical compositions by modulating the exposure time to a biological medium – Dulbecco's Modified Eagle Medium(DMEM). These nanoengineered Zn implants exhibited tunable degradation rates. The nanostructures enhanced human osteoblast attachment, proliferation, and differentiation following direct contact, and improved macrophage function by promoting pseudopod formation and transitioning from a pro‐inflammatory M1 to a pro‐reparative M2 phenotype. In vivo studies show that the surface‐engineered implants effectively promoted tissue integration via M2 macrophage polarization, resulting in a favorable immunomodulatory environment, and increased collagen deposition. Proteomic analyses show that the tissues in the vicinity of the surface‐engineered Zn implants are enriched with proteins related to key wound healing biological mechanisms such as cell adhesion, cytoskeletal structural arrangement, and immune response. This study highlights the improved biocompatibility and anti‐inflammatory effects of surface‐engineered Zn, with important implications for the clinical translation of biodegradable Zn‐based orthopedic implants. [ABSTRACT FROM AUTHOR]

Features of the extracellular matrix, along with biochemical factors, have a momentous impress in making genes on and/or off. The interaction of cells and the extracellular matrix is mediated by integrins. Therefore, these molecules have pivotal roles in regulating cell behaviors. Integrins include a group of molecules with a variety of characteristics that can affect different molecular cascades. Considering the importance of these molecules in tissue regeneration after injury, it is necessary to know well the integrins involved in the process of connecting cells to the extracellular matrix in each tissue. With the increase in life expectancy, bone tissue engineering has received more attention from researchers. Integrins are critical components in osteoblast differentiation, survival, and bone mechanotransduction. During osteogenic differentiation in stem cells, specific integrins facilitate multiple signaling pathways through their cytoplasmic domain, leading to the induction of osteogenic differentiation. Also, due to the importance of using biomaterials in bone tissue engineering, efforts have been made to design and use biomaterials with maximum interaction with integrins. Notably, the use of RGD peptide or fibronectin for surface modification is a well-established and commonly employed approach to manipulate integrin activity. This review article looks into integrins' role in bone development and regeneration. It then goes on to explore the complex mechanisms by which integrins contribute to these processes. In addition, this review discusses the use of natural and synthetic biomaterials that target integrins to promote bone regeneration. [ABSTRACT FROM AUTHOR]

Biofilms are responsible for over 60% of nosocomial infections. The focus of this study was to investigate the antioxidant, antibacterial, antibiofilm, and anti-motility activities of Gardenia volkensii, Carissa bispinosa, Peltophorum africanum , and Senna petersiana. Antioxidant activity was evaluated using free radical (DPPH) scavenging and ferric reducing power assays. Antibacterial and antibiofilm activities were evaluated using the broth micro-dilution and the crystal violet assays, respectively. Anti-motility was evaluated using anti-swarming activities, and the brine shrimp lethality assay was used for cytotoxicity. Gardenia volkensii and C. bispinosa acetone extracts had low EC50 values of 9.59 and 9.99 μg ml−1on the free-radical scavenging activity, respectively. All the plant extracts demonstrated broad-spectrum antibacterial activity against Klebsiella pneumoniae, Pseudomonasa aeruginosa, Escherichia coli, Enterococcus faecalis , and Staphylococcus aureus [minimum inhibitory concentration (MIC) < 0.63 mg ml−1]. The initial cell adherence stage of P. aeruginosa and E. coli was the most susceptible stage where sub-MICs resulted in inhibitions >50%. Peltophorum africanum had the least cytotoxic effects. All extracts had anti-motility activity against P. aeruginosa and E. coli. This study showed that not only do the plants have strong antibacterial activity but had noteworthy inhibition (>50%) of initial cell adherence and may be suitable candidates for the treatment of nosocomial pathogens. [ABSTRACT FROM AUTHOR]

Tunable hydrogels have gained significant attention in the bioengineering field due to their designer preparation approach. Towards this end, gelatine stands out as a promising candidate owing to its desirable attributes, such as biocompatibility, ability to support cell adhesion and proliferation, biodegradability, and cost-effectiveness. This study presents the preparation of a robust gelatine hydrogel employing sacran aldehyde (SDA) as a natural cross-linker. The resulting SDA-cross-linked gelatine hydrogels (GSDA) display an optimal compressive stress of 0.15 MPa at 50% strain, five times higher than pure gelatine hydrogel. As SDA cross-linking concentration is increased, the swelling capacity of GSDA declines. This decline in swelling capacity, from 80% to 40%, is a result of strong crosslinking of gelatin with SDA. Probing further with FT-IR spectroscopy and SEM at the micron scale unveiled a dual-cross-linking mechanism within the hydrogels. This mechanism encompasses both short- and long-range covalent cross-linking, along with thermo-induced physical cross-linking, resulting in a significant enhancement of the load-bearing capacity of the fabricated hydrogels. [ABSTRACT FROM AUTHOR]

Aspergillus flavus, a fungus known for producing aflatoxins, poses significant threats to agriculture and global health. Flavonoids, plant-derived compounds, inhibit A. flavus proliferation and mitigate aflatoxin production, although the precise molecular and physical mechanisms underlying these effects remain poorly understood. In this study, we investigated three flavonoids—apigenin, luteolin, and quercetin—applied to A. flavus NRRL 3357. We determined the following: (1) glycosylated luteolin led to a 10% reduction in maximum fungal growth capacity; (2) quercetin affected cell wall integrity by triggering extreme mycelial collapse, while apigenin and luteolin caused peeling of the outer layer of cell wall; (3) luteolin exhibited the highest antioxidant capacity in the environment compared to apigenin and quercetin; (4) osmotic stress assays did not reveal morphological defects; (5) flavonoids promoted cell adherence, a precursor for biofilm formation; and (6) RNA sequencing analysis revealed that flavonoids impact expression of putative cell wall and plasma membrane biosynthesis genes. Our findings suggest that the differential effects of quercetin, luteolin, and apigenin on membrane integrity and biofilm formation may be driven by their interactions with fungal cell walls. These insights may inform the development of novel antifungal additives or plant breeding strategies focusing on plant-derived compounds in crop protection. [ABSTRACT FROM AUTHOR]

Various strategies have been employed to improve the reliability of 2D, 3D, and co-culture in vitro models of nonalcoholic fatty liver disease, including using extracellular matrix proteins such as collagen I to promote cell adhesion. While studies have demonstrated the significant benefits of culturing cells on collagen I, its effects on the HepG2 cell line after exposure to palmitate (PA) have not been investigated. Therefore, this study aimed to assess the effects of PA-induced lipotoxicity in HepG2 cultured in the absence or presence of collagen I. HepG2 cultured in the absence or presence of collagen I was exposed to PA, followed by analyses that assessed cell proliferation, viability, adhesion, cell death, mitochondrial respiration, reactive oxygen species production, gene and protein expression, and triacylglycerol accumulation. Culturing HepG2 on collagen I was associated with increased cell proliferation, adhesion, and expression of integrin receptors, and improved cellular spreading compared to culturing them in the absence of collagen I. However, PA-induced lipotoxicity was greater in collagen I-cultured HepG2 than in those cultured in the absence of collagen I and was associated with increased α2β1 receptors. In summary, the present study demonstrated for the first time that collagen I-cultured HepG2 exhibited exacerbated cell death following exposure to PA through integrin-mediated death. The findings from this study may serve as a caution to those using 2D models or 3D scaffold-based models of HepG2 in the presence of collagen I. [ABSTRACT FROM AUTHOR]

Essentially all plasma membrane proteins are glycosylated, and their activity is regulated by tuning their cell surface dynamics. This is achieved by glycan-binding proteins of the galectin family that either retain glycoproteins within lattices or drive their endocytic uptake via the clathrin-independent glycolipid-lectin (GL-Lect) mechanism. Here, we have used immunofluorescence-based assays to analyze how lattice and GL-Lect mechanisms affect the internalization of the cell adhesion and migration glycoprotein α5β1 integrin. In retinal pigment epithelial (RPE-1) cells, internalized α5β1 integrin is found in small peripheral endosomes under unperturbed conditions. Pharmacological compounds were used to competitively inhibit one of the galectin family members, galectin-3 (Gal3), or to inhibit the expression of glycosphingolipids, both of which are the fabric of the GL-Lect mechanism. We found that under acute inhibition conditions, endocytic uptake of α5β1 integrin was strongly reduced, in agreement with previous studies on the GL-Lect driven internalization of the protein. In contrast, upon prolonged inhibitor treatment, the uptake of α5β1 integrin was increased, and the protein was now internalized by alternative pathways into large perinuclear endosomes. Our findings suggest that under these prolonged inhibitor treatment conditions, α5β1 integrin containing galectin lattices are dissociated, leading to an altered endocytic compartmentalization. [ABSTRACT FROM AUTHOR]

Introduction: During the Epithelial-mesenchymal Transition (EMT) process, cells undergo a transformation in which they lose their epithelial characteristics and acquire mesenchymal traits. This phenomenon was observed during the metastatic stage of neoplastic disorders, such as cervical cancer. Certain indicators are present during EMT. Aim: To evaluate the role of EMT in utero-cervical carcinoma by analysing the expressions of E-cadherin and vimentin in histopathologically confirmed cases. Materials and Methods: This retrospective cross-sectional study was conducted over a period of two years, from January 1, 2013, to December 31, 2014, at the Department of Pathology in a tertiary care centre and referral hospital. A total of 50 histopathologically confirmed cases of utero-cervical Squamous Cell Carcinoma (SCC) were included in this study. These case were analysed focusing on variables such as age, age at marriage, parity, family history, and hormonal intake. Tumour stages and grades were assessed alongside E-cadherin and vimentin expressions using Immunohistochemistry (IHC). Results were statistically analysed, and the database was created in MS Excel (Version 2007) and analysed using IBM Statistical Package for the Social Sciences (SPSS) Statistics software version 20.0, with significance set at p<0.05. Results: Most cases occurred in the seventh decade of life (42%, 21/50). Out of the 50 tumours studied, 7 (14%) had a positive history of cervical carcinoma, and 6 (12%) had a positive history of hormonal intake. The cervical tumour stages and grades showed statistical significance in relation to family history (p-value=0.001, p-value=0.007) and hormonal intake (p-value<0.001), strongly indicating evidence against the null hypothesis. A total of 4 (8%) cases showed positive lymph node involvement, all of which were in stage 3; among these, 3 (75%) were in grade 3 and 1 (25%) was in grade 2. E-cadherin expression was higher in lower grade and lower stage tumours, while vimentin expression was higher in higher grade and higher stage tumours, as well as in all four lymph node-positive cases. Therefore, the downregulation of E-cadherin and the upregulation of vimentin expression signify EMT. Conclusion: The study concludes that E-cadherin and vimentin play crucial roles in EMT in cervical tumours. E-cadherin was more prevalent in lower grade and stage tumours, while vimentin was more common in higher grade and stage tumours, as well as in all lymph node-positive cases. Cervical tumour stages and grades were significantly associated with family history and hormonal intake. Despite contradictory findings in clinical trials, EMT markers like E-cadherin and vimentin will remain important in future research on cervical carcinoma. [ABSTRACT FROM AUTHOR]

Cell adhesion proteins localize to epithelial and endothelial cell membranes to form junctional complexes between neighboring cells or between cells and the underlying basement membrane. The structural and functional integrities of these junctions are critical to establish cell polarity and maintain tissue barrier function, while also facilitating leukocyte migration and adhesion to sites of inflammation. In addition to their adhesive properties, however, junctional proteins can also serve important noncanonical functions in inflammatory signaling and transcriptional regulation. Intriguingly, recent work has unveiled novel roles for cell adhesion proteins as both signaling initiators and downstream targets during inflammation. In this review, we discuss both the traditional functions of junction proteins in cell adhesion and tissue barrier function as well as their noncanonical signaling roles that have been implicated in facilitating diverse inflammatory pathologies. [ABSTRACT FROM AUTHOR]

Fluid shear stress (FSS) from blood flow, sensed by the vascular endothelial cells (ECs) that line all blood vessels, regulates vascular development during embryogenesis, controls adult vascular physiology and determines the location of atherosclerotic plaque formation. Although a number of papers have reported a crucial role for cell-cell adhesions or adhesion receptors in these processes, a recent publication has challenged this paradigm, presenting evidence that ECs can very rapidly align in fluid flow as single cells without cell–cell contacts. To address this controversy, four independent laboratories assessed EC alignment in fluid flow across a range of EC cell types. These studies demonstrate a strict requirement for cell-cell contact in shear stress sensing over timescales consistent with previous literature and inconsistent with the newly published data. [ABSTRACT FROM AUTHOR]

Our study highlights the apoptosis, cell cycle, DNA ploidy, and autophagy molecular mechanisms network to identify prostate pathogenesis and its prognostic role. Caspase 3/7 expressions, cell cycle, adhesion glycoproteins, autophagy, nuclear shrinkage, and oxidative stress by flow-cytometry analysis are used to study the BPH microenvironment's heterogeneity. A high late apoptosis expression by caspases 3/7 activity represents an unfavorable prognostic biomarker, a dependent predictor factor for cell adhesion, growth inhibition by arrest in the G2/M phase, and oxidative stress processes network. The heterogeneous aggressive phenotype prostate adenoma primary cell cultures present a high S-phase category (>12%), with an increased risk of death or recurrence due to aneuploid status presence, representing an unfavorable prognostic biomarker, a dependent predictor factor for caspase 3/7 activity (late apoptosis and necrosis), and cell growth inhibition (G2/M arrest)-linked mechanisms. Increased integrin levels in heterogenous BPH cultures suggest epithelial–mesenchymal transition (EMT) that maintains an aggressive phenotype by escaping cell apoptosis, leading to the cell proliferation necessary in prostate cancer (PCa) development. As predictor biomarkers, the biological mechanisms network involved in apoptosis, the cell cycle, and autophagy help to establish patient prognostic survival or target cancer therapy development. [ABSTRACT FROM AUTHOR]

The infiltration of immune cells into the central nervous system mediates the development of autoimmune neuroinflammatory diseases. We previously showed that the loss of either Fabp5 or calnexin causes resistance to the induction of experimental autoimmune encephalomyelitis (EAE) in mice, an animal model of multiple sclerosis (MS). Here we show that brain endothelial cells lacking either Fabp5 or calnexin have an increased abundance of cell surface CD200 and soluble CD200 (sCD200) as well as decreased T-cell adhesion. In a tissue culture model of the blood–brain barrier, antagonizing the interaction of CD200 and sCD200 with T-cell CD200 receptor (CD200R1) via anti-CD200 blocking antibodies or the RNAi-mediated inhibition of CD200 production by endothelial cells increased T-cell adhesion and transmigration across monolayers of endothelial cells. Our findings demonstrate that sCD200 produced by brain endothelial cells regulates immune cell trafficking through the blood–brain barrier and is primarily responsible for preventing activated T-cells from entering the brain. [ABSTRACT FROM AUTHOR]

In recent years, with the advent of a super-aged society, lifelong dental care has gained increasing emphasis, and implant therapy for patients with an edentulous jaw has become a significant option. However, for implant therapy to be suitable for elderly patients with reduced regenerative and immunological capabilities, higher osteoconductive and antimicrobial properties are required on the implant surfaces. Silicon nitride, a non-oxide ceramic known for its excellent mechanical properties and biocompatibility, has demonstrated high potential for inducing hard tissue differentiation and exhibiting antibacterial properties. In this study, silicon nitride was deposited on pure titanium metal surfaces and evaluated for its biocompatibility and antibacterial properties. The findings indicate that silicon nitride improves the hydrophilicity of the material surface, enhancing the initial adhesion of rat bone marrow cells and promoting hard tissue differentiation. Additionally, the antibacterial properties were assessed using Staphylococcus aureus, revealing that the silicon nitride-coated surfaces exhibited significant antibacterial activity. Importantly, no cytotoxicity was observed, suggesting that silicon nitride-coated titanium could serve as a novel implant material. [ABSTRACT FROM AUTHOR]

Purpose: Glaucoma, one of the leading causes of irreversible blindness, is a common progressive optic neuropathy characterised by visual field defects and structural changes to the optic nerve head (ONH). There is extracellular matrix (ECM) accumulation and fibrosis of the lamina cribrosa (LC) in the ONH, and consequently increased tissue stiffness of the LC connective tissue. Integrins are cell surface proteins that provide the key molecular link connecting cells to the ECM and serve as bidirectional sensors transmitting signals between cells and their environment to promote cell adhesion, proliferation, and remodelling of the ECM. Here, we investigated the expression of αVβ3 integrin in glaucoma LC cell, and its effect on stiffness-induced ECM gene transcription and cellular proliferation rate in normal (NLC) and glaucoma (GLC) LC cells, by down-regulating αVβ3 integrin expression using cilengitide (a known potent αVβ3 and αVβ5 inhibitor) and β3 integrin siRNA knockdown. Methods: GLC cells were compared to age-matched controls NLC to determine differential expression levels of αVβ3 integrin, ECM genes (Col1A1, α-SMA, fibronectin, vitronectin), and proliferation rates. The effects of αVβ3 integrin blockade (with cilengitide) and silencing (with a pool of four predesigned αVβ3 integrin siRNAs) on ECM gene expression and proliferation rates were evaluated using both reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting in the human NLC cells cultured on soft (4 kPa) and stiff (100 kPa) substrate and in GLC cells grown on standard plastic plates. Results: αVβ3 integrin gene and protein expression were enhanced (p < 0.05) in GLC cells as compared to NLC. Both cilengitide and siRNA significantly reduced αVβ3 expression in GLC. When NLC were grown in the stiff substrate, cilengitide and siRNA also significantly reduced the increased expression in αVβ3, ECM components, and proliferation rate. Conclusions: Here, we provide evidence of cilengitide- and siRNA-mediated silencing of αVβ3 integrin expression, and inhibition of ECM synthesis in LC cells. Therefore, αVβ3 integrin may be a promising target for the development of novel anti-fibrotic therapies for treating the LC cupping of the ONH in glaucoma. [ABSTRACT FROM AUTHOR]

Objectives This study focused on the serology, clinical characteristics, and hemolytic potential of warm reactive autoantibodies detected by solid phase red cell adherence. Methods Ninety-seven patients with warm autoantibodies were evaluated. Serologic characteristics included the strength of solid phase reactivity, the results of tube-based ancillary testing, direct antiglobulin test and eluate results, and an assessment for contemporaneous alloantibodies. Clinical characteristics of the patients included age, sex, and primary diagnosis. Each patient was also assessed for evidence of hemolysis. Results Most of the 97 study patients were female (63.9%), and the average age was 66 years. Hematologic disorders were the most common diagnosis. A majority (70.1%) of the warm autoantibodies had 3 to 4+ reaction strengths, and approximately 90% had negative testing with at least 1 test tube method. There was an even distribution of direct antiglobulin test reaction strengths, with 74% reactive with anti–immunoglobulin G only. Alloantibodies were identified in 20% of patients. Evidence of hemolysis was identified in only 13 patients (13.4%). Conclusions Warm reactive autoantibodies are more likely to be hemolytic, have strongly reactive indirect and direct antiglobulin tests, remain reactive in tube-based ancillary testing methods, and are seen primarily in patients with hematologic disorders. [ABSTRACT FROM AUTHOR]

Cardiac arrhythmia treatment is a clinical challenge necessitating safer and more effective therapies. Recent studies have highlighted the role of the perinexus, an intercalated disc nanodomain enriched in voltage-gated sodium channels including both Na v 1.5 and β1 subunits, adjacent to gap junctions. These findings offer insights into action potential conduction in the heart. A 19-amino acid SCN1B (β1/β1B) mimetic peptide, βadp1, disrupts VGSC beta subunit-mediated adhesion in cardiac perinexii, inducing arrhythmogenic changes. We aimed to explore βadp1's mechanism and develop novel SCN1B mimetic peptides affecting β1-mediated adhesion. Using patch clamp assays in neonatal rat cardiomyocytes and electric cell substrate impedance sensing (ECIS) in β1-expressing cells, we observed βadp1 maintained inhibitory effects for up to 5 h. A shorter peptide (LQLEED) based on the carboxyl-terminus of βadp1 mimicked this inhibitory effect, while dimeric peptides containing repeated LQLEED sequences paradoxically promoted intercellular adhesion over longer time courses. Moreover, we found a link between these peptides and β1-regulated intramembrane proteolysis (RIP) - a signaling pathway effecting gene transcription including that of VGSC subunits. βadp1 increased RIP continuously over 48 h, while dimeric agonists acutely boosted RIP for up to 6 h. In the presence of DAPT, an RIP inhibitor, βadp1's effects on ECIS-measured intercellular adhesion was reduced, suggesting a relationship between RIP and the peptide's inhibitory action. In conclusion, novel SCN1B (β1/β1B) mimetic peptides are reported with the potential to modulate intercellular VGSC β1-mediated adhesion, potentially through β1 RIP. These findings suggest a path towards the development of anti-arrhythmic drugs targeting the perinexus. [Display omitted] • Voltage-gated sodium channel β1 subunit offers novel anti-arrhythmic target. • β1 mimetic peptides increase regulated intramembrane proteolysis (RIP) of β1. • β1 mimetic peptide monomers decrease β1-mediated adhesion. • β1 mimetic peptide dimers stabilize or increase β1-mediated adhesion. [ABSTRACT FROM AUTHOR]

To fabricate and characterize an innovative gelatin methacryloyl/GelMA electrospun scaffold containing the citrus flavonoid naringenin/NA with osteogenic and anti-inflammatory properties. GelMA scaffolds (15 % w/v) containing 0/Control, 5, 10, or 20 % of NA w/w were obtained via electrospinning. The chemical composition, fiber morphology/diameter, swelling/degradation profile, and NA release were investigated. Cytotoxicity, cell proliferation, adhesion and spreading, total protein/TP production, alkaline phosphatase/ALP activity, osteogenic genes expression (OCN, OPN, RUNX2), and mineralized nodules deposition/MND with human alveolar bone-derived mesenchymal stem cells (aBMSCs) seeded on the scaffolds were assessed. Moreover, aBMSCs seeded on the scaffolds and stimulated with tumor necrosis factor-alpha/TNF-α were submitted to collagen, nitric oxide/NO, interleukin/IL-1α, and IL-6 production assessment. Data were analyzed using ANOVA and t-student/post-hoc tests (α = 5 %). NA-laden scaffolds presented increased fiber diameter, lower swelling capacity, and faster degradation profile over 28 days (p < 0.05). NA release was detected over time. Cell adhesion and spreading, and TP production were similar between GelMA and GelMA+NA5 % scaffolds, while cell proliferation, ALP activity, OCN/OPN/RUNX2 gene expression, and MND were higher for GelMA+NA5 % scaffolds (p < 0.05). Cells seeded on control scaffolds and TNF-α-stimulated presented higher levels of NO, IL-1α/IL-6, and lower levels of collagen (p < 0.05). In contrast, cells seeded on GelMA+NA5 % scaffolds showed downregulation of inflammatory markers and higher collagen synthesis (p < 0.05). GelMA+NA5 % scaffold was cytocompatible, stimulated aBMSCs proliferation and differentiation, and downregulated inflammatory mediators' synthesis, suggesting its therapeutic effect as a multi-target bifunctional scaffold with osteogenic and anti-inflammatory properties for bone tissue engineering. • GelMA+NA 5 % scaffold degradation matches the bone healing timeline. • GelMA+NA 5 % enhanced cell viability and osteoinductive properties. • GelMA+NA 5 % controlled the NO, IL-1α, and IL-6 expression in TNF-a stimulated cells. [ABSTRACT FROM AUTHOR]

Background: Amphoterin-induced gene and open reading frame 2 (AMIGO2) have been reported to be related to the prognosis of colorectal, gastric, and cervical cancer. However, their association with ovarian cancer remains unclear. This study aimed to elucidate the role of AMIGO2 in ovarian cancer. Methods: AMIGO2 expression was evaluated using immunohistochemistry in patients with ovarian serous carcinoma. We validated in vitro studies using four serous ovarian cancer cell lines and in vivo studies using a murine model. Results: The AMIGO2-high group had significantly shorter progression-free survival (PFS) than the AMIGO2-low group. The predictive index of the AMIGO2-high group was considerably higher than that of the AMIGO2-low group. The rate of complete cytoreductive surgery was lower in the AMIGO2-high group than in the AMIGO2-low group. Moreover, in vitro studies revealed that four serous ovarian cancer cell lines exhibited AMIGO2 expression and adhesion to mesothelial cells. Adhesion to mesothelial cells was attenuated by AMIGO2 knockdown in SKOV3 and SHIN3 cells. Furthermore, AMIGO2 downregulation in SKOV3 cells significantly suppressed peritoneal dissemination in the murine model. Conclusion: These results suggest that high AMIGO2 expression in serous ovarian carcinoma cells contributes to a poor prognosis by promoting peritoneal metastasis through enhanced cell adhesion to mesothelial cells. [ABSTRACT FROM AUTHOR]

Mg Ga alloys are considered highly potential biodegradable materials, owing to its good mechanical properties and appropriate corrosion resistance. However, it is still far from application due to the lack of biological evaluation. In the present study, biocompatibility, osteogenesis and antibacterial activity of extruded Mg–xGa (x = 1 and 5 wt%) alloys were investigated by in vitro cell culture experiments and in vivo implantation. The cell adhesion and proliferation of osteoblast precursor cells (MC3T3-E1) showed the excellent cytocompatibility of Mg–1Ga and poor cytocompatibility of Mg–5Ga. The osteogenic activity was evaluated and revealed that Ga3+ in the Mg–1Ga extract had the ability to enhance osteogenic differentiation through the facilitation of its early stages. In vivo studies in a rat femoral condyle model revealed that both Mg–1Ga and Mg–5Ga significantly promoted new bone formation without causing any adverse effects. Mg–5Ga exhibited a much higher corrosion rate in vivo than Mg–1Ga. Its osteogenic activity was better due to the rapid release of Mg2+ and Ga3+, but this caused premature structural integrity loss. Mg–1Ga and Mg–5Ga released Ga3+ to inhibit E. coli and S. aureus , with antibacterial rate increasing with Ga content. Our studies demonstrate that Mg–Ga alloys have the potential to be used as osteogenic and antibacterial implant materials. This study evaluates the biocompatibility, osteogenesis, and antibacterial activity of Mg–Ga alloys, which are promising biodegradable materials for medical applications. The study finds that Mg–1Ga exhibits excellent cytocompatibility and promotes osteogenic differentiation, facilitating the early stages of osteoblast precursor cell development. In vivo studies in a rat femoral condyle model reveal that Mg–1Ga and Mg–5Ga significantly promote new bone formation without causing any adverse effects. The antibacterial activity of both alloys is evaluated against E. coli and S. aureus , with the inhibition rate increasing with Ga content. These findings suggest that Mg–Ga alloys have the potential to serve as osteogenic and antibacterial implant materials, providing significant insights into the development of novel biomedical implants. [Display omitted] [ABSTRACT FROM AUTHOR]

Titanium-Niobium (TiNb) alloys are commonly employed in a number of implantable devices, yet concerns exist regarding their use in implantology owing to the biomechanical mismatch between the implant and the host tissue. Therefore, to balance the mechanical performance of the load-bearing implant with bone, TiNb alloys with differing porosities were fabricated by powder metallurgy combined with spacer material. Microstructures and phase constituents were characterized with energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The mechanical properties were tested by uniaxial compression, and the corrosion performance was determined via a potentiodynamic polarization experiment. To evaluate a highly matched potential implant with the host, biocompatibilities such as cell viability and proliferation rate, fibronectin adsorption, plasmid-DNA interaction, and an SEM micrograph showing the cell morphology were examined in detail. The results showed that the alloys displayed open and closed pores with a uniform pore size and distribution, which allowed for cell adherence and other cellular activities. The alloys with low porosity displayed compressive strength between 618 MPa and 1295 MPa, while the alloys with high porosity showed significantly lower strength, ranging from 48 MPa to 331 MPa. The biological evaluation of the alloys demonstrated good cell attachment and proliferation rates. [ABSTRACT FROM AUTHOR]

An ideal extracellular matrix (ECM) replacement scaffold in a three-dimensional cell (3D) culture should induce in vivo-like interactions between the ECM and cultured cells. Highly hydrophilic polyvinyl alcohol (PVA) nanofibers disintegrate upon contact with water, resulting in the loss of their fibrous morphology in cell cultures. This can be resolved by using chemical crosslinkers and post-crosslinking. A crosslinked, water-stable, porous, and optically transparent PVA nanofibrous membrane (NM) supports the 3D growth of various cell types. The binding of cells attached to the porous PVA NM is low, resulting in the aggregation of cultured cells in prolonged cultures. PVA NMs containing integrin-binding peptides of fibronectin and laminin were produced to retain the blended peptides as cell-binding substrates. These peptide-blended PVA NMs promote peptide-specific cell adherence and growth. Various cells, including epithelial cells, cultured on these PVA NMs form layers instead of cell aggregates and spheroids, and their growth patterns are similar to those of the cells cultured on an ECM-coated PVA NM. The peptide-retained PVA NMs are non-stimulatory to dendritic cells cultured on the membranes. These peptide-retaining PVA NMs can be used as an ECM replacement matrix by providing in vivo-like interactions between the matrix and cultured cells. [ABSTRACT FROM AUTHOR]

(1) Background: This systematic review critically appraises and synthesizes evidence from in vitro studies investigating the effects of curcumin nanoparticles on titanium surface modification, focusing on cell adhesion, proliferation, osteogenic differentiation, and mineralization. (2) Methods: A comprehensive electronic search was conducted in PubMed, Cochrane Central Register of Controlled Trials, and Google Scholar databases, yielding six in vitro studies that met the inclusion criteria. The search strategy and study selection process followed PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A qualitative methodological assessment was performed using the SciRAP (Science in Risk Assessment and Policy) method, which evaluated the reporting and methodological quality of the included studies. (3) Results: All six studies consistently demonstrated that curcumin-coated titanium surfaces inhibited osteoclastogenesis and promoted osteogenic activity, evidenced by enhanced cell adhesion, proliferation, osteogenic differentiation, and mineralization. The mean reporting quality score was 91.8 (SD = 5.7), and the mean methodological quality score was 85.8 (SD = 10.50), as assessed by the SciRAP method. Half of the studies used hydroxyapatite-coated titanium as a control, while the other half used uncoated titanium, introducing potential variability in baseline comparisons. (4) Conclusions: This systematic review provides compelling in vitro evidence supporting the osteogenic potential of curcumin nanoparticle-coated titanium surfaces. The findings suggest that this surface modification strategy may enhance titanium implants' biocompatibility and osteogenic properties, potentially improving dental and orthopedic implant outcomes. However, the review highlights significant heterogeneity in experimental designs and a concentration of studies from a single research group. Further research, particularly in vivo studies and clinical trials from diverse research teams, is essential to validate these findings and comprehensively understand the translational potential of this promising surface modification approach. [ABSTRACT FROM AUTHOR]

The strategies used to associate peptide arginylglycylaspartic acid (RGD) with calcium phosphate grafts to enhance cell–biomaterial interactions have been controversial in the literature. Several works have demonstrated that RGD-functionalized hydroxyapatite (HA) surfaces improve cell adhesion, whereas others claim that RGD-loaded HA has an inhibitory effect when serum is present in the biological medium. To investigate such contradictory results, we associated RGD with the HA surface using physical adsorption and chemical bonding methods and evaluated the cell adhesion and spreading in pre-osteoblasts culture with and without fetal bovine serum (FBS). The effect of functionalization methods on the physicochemical characteristics of both surfaces was analyzed using multiscale techniques. Adsorption assays of serum allowed us to estimate the impact of the association method on the HA surface's reactivity. Physically adsorbed RGD did not increase the number of adhered cells due to the weak interactions between the peptide and the surface. Although chemical binding stabilizes RGD on the HA, the functionalization procedure covered the surface with molecules such as (3-aminopropyl)triethoxysilane (APTEs) and carbodiimide, changing the surface's chemical activity. Serum protein adsorption decreased by 90%, revealing a significant reduction in the surface interactions with molecules of the biological medium. The present study's findings showed that the RGD's physical association with HA did not improve cell adhesion and that this phenomenon is highly dependent on the presence of serum proteins. [ABSTRACT FROM AUTHOR]

Objective: Heart failure (HF) pathophysiology in patients with obesity may be distinct. To study these features, we identified obesity‐related biomarkers from 4210 circulating proteins in patients with HF with reduced ejection fraction (HFrEF) and examined associations of these proteins with HF prognosis and biological mechanisms. Methods: In 373 patients with trimonthly blood sampling during a median follow‐up of 2.1 (25th–75th percentile: 1.1–2.6) years, we applied an aptamer‐based multiplex approach measuring 4210 proteins in baseline samples and the last two samples before study end. Associations between obesity (BMI > 30 kg/m2) and baseline protein levels were analyzed. Subsequently, associations of serially measured obesity‐related proteins with biological mechanisms and the primary endpoint (PEP; composite of cardiovascular mortality, HF hospitalization, left ventricular assist device implantation, and heart transplantation) were examined. Results: Obesity was identified in 26% (96/373) of patients. A total of 30% (112/373) experienced a PEP (with obesity: 26% [25/96] vs. without obesity: 31% [87/277]). A total of 141/4210 proteins were linked to obesity, reflecting mechanisms of neuron projection development, cell adhesion, and muscle cell migration. A total of 50/141 proteins were associated with the PEP, of which 12 proteins related to atherosclerosis or hypertrophy provided prognostic information beyond clinical characteristics, N‐terminal pro‐B‐type natriuretic peptide, and high‐sensitivity troponin T. Conclusions: Patients with HFrEF and obesity show distinct proteomic profiles compared to patients with HFrEF without obesity. Obesity‐related proteins are independently associated with HF outcome. These proteins carry potential to improve management of obesity‐related HF and could be leads for future research. [ABSTRACT FROM AUTHOR]

Darier disease (DD) is a rare severe acantholytic skin disease caused by mutations in the ATP2A2 gene that encodes for the sarco/endoplasmic reticulum calcium ATPase isoform 2 (SERCA2). SERCA2 maintains endoplasmic reticulum calcium homeostasis by pumping calcium into the ER, critical for regulating cellular calcium dynamics and cellular function. To date, there is no treatment that specifically targets the disease mechanisms in DD. Dantrolene sodium (Dl) is a ryanodine receptor antagonist that inhibits calcium release from ER to increase ER calcium levels and is currently used for non-dermatological indications. In this study, we first identified dysregulated genes and molecular pathways in DD patient skin, demonstrating downregulation of cell adhesion and calcium homeostasis pathways, as well as upregulation of ER stress and apoptosis. We then show in various in vitro models of DD and SERCA2 inhibition that Dl aided in the retention of ER calcium and promoted cell adhesion. In addition, Dl treatment reduced ER stress and suppressed apoptosis. Our findings suggest that Dl specifically targets pathogenic mechanisms of DD and may be a potential treatment. Synopsis: In this study we show that Dantrolene, an approved ryanodine receptor antagonist, improved various pathophysiological hallmarks of Darier disease in in vitro models of the disease, demonstrating the potential applicability of the drug as a novel therapy. Dantrolene increases ER calcium levels and improves cell adhesion. Dantrolene partially improves ER stress and reduces apoptosis. In this study we show that Dantrolene, an approved ryanodine receptor antagonist, improved various pathophysiological hallmarks of Darier disease in in vitro models of the disease, demonstrating the potential applicability of the drug as a novel therapy. [ABSTRACT FROM AUTHOR]

Extracellular membrane proteins are crucial for mediating cell attachment, recognition, and signal transduction in the testicular microenvironment, particularly germline stem cells. Cadherin 18 (CDH18), a type II classical cadherin, is primarily expressed in the nervous and reproductive systems. Here, we investigated the expression of CDH18 in neonatal porcine prospermatogonia (ProSGs) and murine spermatogonial stem cells (SSCs). Disruption of CDH18 expression did not adversely affect cell morphology, proliferation, self-renewal, or differentiation in cultured porcine ProSGs, but enhanced cell adhesion and prolonged cell maintenance. Transcriptomic analysis indicated that the down-regulation of CDH18 in ProSGs significantly up-regulated genes and signaling pathways associated with cell adhesion. To further elucidate the function of CDH18 in germ cells, Cdh18 knockout mice were generated, which exhibited normal testicular morphology, histology, and spermatogenesis. Transcriptomic analysis showed increased expression of genes associated with adhesion, consistent with the observations in porcine ProSGs. The interaction of CDH18 with β-catenin and JAK2 in both porcine ProSGs and murine SSCs suggested an inhibitory effect on the canonical Wnt and JAK-STAT signaling pathways during CDH18 deficiency. Collectively, these findings highlight the crucial role of CDH18 in regulating cell adhesion in porcine ProSGs and mouse SSCs. Understanding this regulatory mechanism provides significant insights into the testicular niche. [ABSTRACT FROM AUTHOR]

It is a long‐standing challenge to exploit cellular uptake mechanisms to deliver desired cargo into cells, for example, specific drugs or gene editing techniques. This study introduces a bioinspired material approach where nanoparticles are presented at the ventral side of cells adhering to engineered extracellular matrices. The effect of matrix stiffness on cell adhesion and mechanics, as well as on particle internalization by clathrin‐mediated endocytosis (CME), is investigated for varying particle size and surface functionalization. The results presented here show that substrate stiffness affects both cell adhesion and particle internalization, with softer substrates promoting higher levels of particle uptake. However, the activation of the CME pathway, either mechanically by particle size or functionally by receptor binding, regulates the sensitivity of cellular particle uptake to matrix stiffness. Finally, adeno‐associated viruses as the leading platform for therapeutic gene delivery are used as model cargo to showcase the importance of considering multiple components when designing delivery systems. These findings indicate that particle uptake is a multifaceted process that can be improved by the appropriate combination of extracellular environment mechanics and cargo properties. [ABSTRACT FROM AUTHOR]

SLC4A11 is the most abundant membrane transport protein in corneal endothelial cells. Its functional presence is necessary to support the endothelial fluid pump that draws fluid from the corneal stroma, preventing corneal edema. Several molecular actions have been proposed for SLC4A11 including H2O transport and cell adhesion. One of the most reproduced actions that SLC4A11 mediates is a H+ (or OH-) conductance that is enhanced in the presence of NH4Cl. The mechanism by which this occurs is controversial with some providing evidence in favor of NH3-H+ cotransport and others providing evidence for uncoupled H+ transport that is indirectly stimulated by the effects of NH4Cl upon intracellular pH and membrane potential. In the present study we provide new evidence and revisit previous studies, to support a model in which NH4Cl causes direct allosteric activation of SLC4A11 by means of an acidic shift in the intracellular pK (pKi) that governs the relationship between intracellular pH (pHi) and SLC4A11 H+-conductance. These findings have important implications for the assignment of a physiological role for SLC4A11. [ABSTRACT FROM AUTHOR]

Background: Toxoplasma gondii (T. gondii) is a widespread, zoonotic protozoan intracellular parasite with a complex life cycle, which can cause toxoplasmosis, a potentially serious disease. During the invasion process, T. gondii proteins first bind to the relevant host cell receptors, such as glycosaminoglycan molecule (GAG-binding motif), which is one of the main receptors for parasites or virus to infect host cells. However, research on TGME49_216510 (T. gondii Trx21), a protein from Toxoplasma gondii, is limited. Methods: Bioinformatics analysis of the Trx21 protein was performed firstly. And specific primers were then designed using the conserved domain and GAG-binding motif to amplify, express, and purify a fragment of the Trx21 protein. The purified Trx21-GST protein was used for antioxidant and cell adhesion experiments. Simultaneously, mice were immunized with Trx21-His to generate specific polyclonal antibodies for subcellular localization analysis. Results: The Trx21 protein, consisting of 774 amino acids, included a transmembrane region, three GAG-binding motifs, and a Thioredoxin-like domain. The recombinant Trx21-His protein had a molecular mass of about 31 kDa, while the Trx21-GST protein had a molecular mass of about 55 kDa, which was analyzed by SDS-PAGE and Western blot. Subcellular localization analysis by IFA revealed that Trx21 is predominantly distributed in the cytoplasm of T. gondii. Furthermore, Trx21 exhibited a protective effect on supercoiled DNA against metal-catalyzed oxidation (MCO) and demonstrated adhesion abilities to Vero cells. Conclusions: These results indicate that Trx21 plays an important role in host cell interaction and oxidative damage. [ABSTRACT FROM AUTHOR]

The contractile apparatus, stress fiber (SF), is connected to the cell adhesion machinery, focal adhesion (FA), at the termini of SF. The SF-FA complex is essential for various mechanical activities of cells, including cell adhesion to the extracellular matrix (ECM), ECM rigidity sensing, and cell migration. This mini-review highlights the importance of SF mechanics in these cellular activities. Actin-crosslinking proteins solidify SFs by attenuating myosindriven flows of actin and myosin filaments within the SF. In the solidified SFs, viscous slippage between actin filaments in SFs and between the filaments and the surrounding cytosol is reduced, leading to efficient transmission of myosin-generated contractile force along the SFs. Hence, SF solidification via actin crosslinking ensures exertion of a large force to FAs, enabling FA maturation, ECM rigidity sensing and cell migration. We further discuss intracellular mechanisms for tuning crosslinker-modulated SF mechanics and the potential relationship between the aberrance of SF mechanics and pathology including cancer. [ABSTRACT FROM AUTHOR]

Hydrogels with cell adhesive moieties stand out as promising materials to enhance tissue healing and regeneration. Nonetheless, bacterial infections of the implants represent an unmet major concern. In the present work, we developed an alginate hydrogel modified with a multifunctional peptide containing the RGD cell adhesive motif in combination with an antibacterial peptide derived from the 1–11 region of lactoferrin (LF). The RGD‐LF branched peptide was successfully anchored to the alginate backbone by carbodiimide chemistry, as demonstrated by 1H NMR and fluorescence measurements. The functionalized hydrogel presented desirable physicochemical properties (porosity, swelling and rheological behavior) to develop biomaterials for tissue engineering. The viability of mesenchymal stem cells (MSCs) on the peptide‐functionalized hydrogels was excellent, with values higher than 85 % at day 1, and higher than 95 % after 14 days in culture. Moreover, the biological characterization demonstrated the ability of the hydrogels to significantly enhance ALP activity of MSCs as well as to decrease bacterial colonization of both Gram‐positive and Gram‐negative models. Such results prove the potential of the functionalized hydrogels as novel biomaterials for tissue engineering, simultaneously displaying cell adhesive activity and the capacity to prevent bacterial contamination, a dual bioactivity commonly not found for these types of hydrogels. [ABSTRACT FROM AUTHOR]

Protein tyrosine phosphatases non-receptor type (PTPNs) have been studied extensively in the context of the adaptive immune system; however, their roles beyond immunoregulation are less well explored. Here we identify novel functions for the conserved C. elegans phosphatase PTPN-22, establishing its role in nematode molting, cell adhesion, and cytoskeletal regulation. Through a non-biased genetic screen, we found that loss of PTPN-22 phosphatase activity suppressed molting defects caused by loss-of-function mutations in the conserved NIMA-related kinases NEKL-2 (human NEK8/NEK9) and NEKL-3 (human NEK6/NEK7), which act at the interface of membrane trafficking and actin regulation. To better understand the functions of PTPN-22, we carried out proximity labeling studies to identify candidate interactors of PTPN-22 during development. Through this approach we identified the CDC42 guanine-nucleotide exchange factor DNBP-1 (human DNMBP) as an in vivo partner of PTPN-22. Consistent with this interaction, loss of DNBP-1 also suppressed nekl-associated molting defects. Genetic analysis, co-localization studies, and proximity labeling revealed roles for PTPN-22 in several epidermal adhesion complexes, including C. elegans hemidesmosomes, suggesting that PTPN-22 plays a broad role in maintaining the structural integrity of tissues. Localization and proximity labeling also implicated PTPN-22 in functions connected to nucleocytoplasmic transport and mRNA regulation, particularly within the germline, as nearly one-third of proteins identified by PTPN-22 proximity labeling are known P granule components. Collectively, these studies highlight the utility of combined genetic and proteomic approaches for identifying novel gene functions. Author summary: The human protein, PTPN22, has been studied extensively within the context of the adaptive immune system and mutations that affect PTPN22 function are implicated in multiple autoimmune disorders. Curiously, PTPN22 is conserved throughout the animal kingdom, including in the invertebrate roundworm Caenorhabditis elegans, which lack an adaptive immune system. Using several non-biased approaches to uncover novel protein functions, we identified roles for the Caenorhabditis elegans PTPN22 ortholog, PTPN-22, in a several different cell biological processes including functions related to epithelial cell and tissue connectivity. These studies, along with our analysis of the cellular and subcellular locations in which PTPN-22 is present during development, indicate that the worm PTPN-22 carries out a diverse range of functions. Our studies indicate that, in addition to critical roles within the immune-system, PTPN22 family members may carry additional functions that are conserved throughout the animal kingdom, a finding supported by several studies carried out on human PTPN22 suggesting roles in cell-cell adhesion. [ABSTRACT FROM AUTHOR]

Bone tissue engineering necessitates the development of scaffolds with optimal properties to provide a suitable microenvironment for cell adhesion, proliferation, and osteogenic differentiation. The selection of appropriate scaffold materials remains a critical challenge in this field. In this study, we aimed to address this challenge by evaluating and comparing the performance of hydrogel scaffolds reinforced with β‐tricalcium phosphate (β‐TCP), allograft, and a combination of allograft and strontium hydroxyapatite (SrHA). In this study, scaffolds containing the following compounds with a weight ratio of 75 : 25 : 50 were made using a 3D printer: group (1) alginate + gelatin + β‐TCP (TCP), group (2) alginate + gelatin + allograft (Allo), and group (3) alginate + gelatin + allograft + strontium hydroxyapatite (Str). Stem cells extracted from rat bone marrow (rBMSCs) were cultured on scaffolds, and cell proliferation and differentiation tests were performed. Also, the physical and chemical properties of the scaffolds were investigated. The two/one‐way analysis of variance (ANOVA) by Tukey's post hoc test was performed. There was no significant difference between scaffolds with pore size and porosity. TCP scaffolds' mechanical strength and degradation rate were significantly lower than the other two groups (P < 0.05). Also, the swelling ratio of Allo scaffolds was higher than in other samples. The amount of cell proliferation in the samples of the TCP group was lower than the other two, and the Allo samples had the best results in this concern (P < 0.01). However, the scaffolds containing strontium hydroxyapatite had significantly higher bone differentiation compared to the other two groups, and the lowest results were related to the scaffolds containing β‐TCP. Hydrogel scaffolds reinforced with allograft or its combination with strontium showed better physicochemical and biological behavior compared to those reinforced with β‐TCP. Besides, adding strontium had a limited impact on the physicochemical features of allograft‐containing scaffolds while improving their potential to induce osteogenic differentiation. [ABSTRACT FROM AUTHOR]

The advent of the Coronavirus Disease 2019 (COVID-19) has presented a substantial and urgent global public health issue. Biomarkers have the potential to be utilized for the identification of endothelium and/or alveolar epithelial damage in instances of COVID-19 infection. to evaluate the levels of Intercellular adhesion molecule-1 (ICAM-1) and Vascular cell adhesion molecule (VCAM-1) biomarkers in hospitalized patients who tested positive for COVID-19 infection using Polymerase Chain Reaction (PCR) with the virus specific Immunoglobulins; IgM, and IgG testing. This can help with improved clinical management and treatment programs. A case-control study that involved 90 hospitalized patients who tested positive for COVID-19 and 40 apparently healthy control patients, subjects in both groups underwent nasopharyngeal swabs for PCR and blood sample collection for evaluation of serum; IgM, IgG, ICAM-1 and VCAM-1 levels. Males made up the vast majority of the patients (78.9%), with only a minor percentage of females (21.1%) P value 0.1641. Furthermore, every patient in this study had a minimum of one risk factor for COVID-19. The investigator’s results show that COVID-19 patients had higher amounts of endothelial cell adhesion indicators (ICAM-1 and VCAM-1) with mean values of 126.27 ± 89.51 ng/mL and 109.74 ± 96.57 ng/mL respectively. While, ICAM-1 and VCAM-1, were present at normal levels in the control group with difference P value 0.0028 and 0.0032 in comparison to the patient’s group respectively. The adhesive markers ICAM and VCAM play a crucial role in the development of COVID-19 and the strong endothelial activation and dysfunction linked to both acute and persistent immunological responses is shown by the substantial correlation found in COVID-19 patients between the presence of IgM and IgG antibodies and higher levels of ICAM-1 and VCAM-1. [ABSTRACT FROM AUTHOR]

Integrin β4 (ITGB4) is a transmembrane protein that functions as a mechanosensor, mediating the bidirectional exchange of information between the intracellular and extracellular matrices. ITGB4 plays a critical role in cell adhesion, migration, and signaling. Numerous studies have implicated ITGB4 as a key facilitator of tumor migration and invasion. This review provides a foundational description of the mechanisms by which ITGB4 regulates tumor migration and invasion through pathways involving focal adhesion kinase (FAK), protein kinase B (AKT), and matrix metalloproteinases (MMPs). These mechanisms encompass epithelial-mesenchymal transition (EMT), phosphorylation, and methylation of associated molecules. Additionally, this review explores the role of ITGB4 in the migration and invasion of prevalent clinical tumors, including those of the digestive system, breast, and prostate. [ABSTRACT FROM AUTHOR]

Imaging and characterizing the dynamics of cellular adhesion in blood samples is of fundamental importance in understanding biological function. In vitro microscopy methods are widely used for this task but typically require diluting the blood with a buffer to allow for transmission of light. However, whole blood provides crucial signaling cues that influence adhesion dynamics, which means that conventional approaches lack the full physiological complexity of living microvasculature. We can reliably image cell interactions in microfluidic channels during whole blood flow by motion blur microscopy (MBM) in vitro and automate image analysis using machine learning. MBM provides a low cost, easy to implement alternative to intravital microscopy, for rapid data generation where understanding cell interactions, adhesion, and motility is crucial. MBM is generalizable to studies of various diseases, including cancer, blood disorders, thrombosis, inflammatory and autoimmune diseases, as well as providing rich datasets for theoretical modeling of adhesion dynamics. Monitoring cellular adhesion in blood samples is of fundamental importance, but conventional approaches may not capture the full physiological complexity of microscale flow in living contexts. Here, the authors present motion blur microscopy and machine learning-based image analysis to study cell interactions in microfluidic channels during whole blood flow. [ABSTRACT FROM AUTHOR]

Cell adhesion to the extracellular matrix and its natural outcome of cell spreading, along with the maintenance of barrier activity, are essential behaviors of epithelial cells, including retinal pigment epithelium (RPE). Disruptions in these characteristics can result in severe vision-threatening diseases such as diabetic macular edema and age-related macular degeneration. However, the precise mechanisms underlying how RPE cells regulate their barrier integrity and cell spreading are not fully understood. This study aims to elucidate the relative importance of upper glycolytic components in governing these cellular behaviors of RPE cells. Electric Cell-Substrate Impedance Sensing (ECIS) technology was utilized to assess in real-time the effects of targeting various upper glycolytic enzymes on RPE barrier function and cell spreading by measuring cell resistance and capacitance, respectively. Specific inhibitors used included WZB117 for Glut1 inhibition, Lonidamine for Hexokinase inhibition, PFK158 for PFKFB3/PFK axis inhibition, and TDZD-8 for Aldolase inhibition. Additionally, the viability of RPE cells was evaluated using a lactate dehydrogenase (LDH) cytotoxicity assay. The most significant decrease in electrical resistance and increase in capacitance of RPE cells were observed due to dose-dependent inhibition of Glut1 using WZB117, as well as Aldolase inhibition with TDZD-8. LDH level analysis at 24–72 h post-treatment with WZB117 (1 and 10 μM) or TDZD-8 (1 μM) showed no significant difference compared to the control, indicating that the disruption of RPE functionality was not attributed to cell death. Lastly, inhibition of other upper glycolytic components, including PFKFB3/PFK with PFK158 or Hexokinase with Lonidamine, did not significantly affect RPE cell behavior. This study provides insights into the varied roles of upper glycolytic components in regulating the functionality of RPE cells. Specifically, it highlights the critical roles of Glut1 and Aldolase in preserving barrier integrity and promoting RPE cell adhesion and spreading. Such understanding will guide the development of safe interventions to treat RPE cell dysfunction in various retinal disorders. [ABSTRACT FROM AUTHOR]

Pemphigus is an autoimmune disease that affects the skin and mucous membranes, induced by the deposition of pemphigus IgG, which mainly targets desmogleins 1 and 3 (Dsg1 and 3). This autoantibody causes steric interference between Dsg1 and 3 and the loss of cell adhesion, producing acantholysis. This molecule and its cellular effects are clinically reflected as intraepidermal blistering. Pemphigus vulgaris-IgG (PV-IgG) binding involves p38MAPK-signaling-dependent caspase-3 activation. The present work assessed the in vitro effect of PV-IgG on the adherence of HaCaT cells dependent on caspase-3. PV-IgG induced cell detachment and apoptotic changes, as demonstrated by annexin fluorescent assays. The effect of caspase-3 induced by PV-IgG was suppressed in cells pre-treated with caspase-3-shRNA, and normal IgG (N-IgG) as a control had no relevant effects on the aforementioned parameters. The results demonstrated that shRNA reduces caspase-3 expression, as measured via qRT-PCR and via Western blot and immunofluorescence, and increases cell adhesion. In conclusion, shRNA prevented in vitro cell detachment and the late effects of apoptosis induced by PV-IgG on HaCaT cells, furthering our understanding of the molecular role of caspase-3 cell adhesion dependence in pemphigus disease. [ABSTRACT FROM AUTHOR]