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1.
Bioessays ; 46(5): e2300223, 2024 May.
Article in English | MEDLINE | ID: mdl-38522027

ABSTRACT

Ageing causes progressive decline in metabolic, behavioural, and physiological functions, leading to a reduced health span. The extracellular matrix (ECM) is the three-dimensional network of macromolecules that provides our tissues with structure and biomechanical resilience. Imbalance between damage and repair/regeneration causes the ECM to undergo structural deterioration with age, contributing to age-associated pathology. The ECM 'Ageing Across the Life Course' interdisciplinary research network (ECMage) was established to bring together researchers in the United Kingdom, and internationally, working on the emerging field of ECM ageing. Here we report on a consultation at a joint meeting of ECMage and the Medical Research Council / Versus Arthritis Centre for Integrated Research into Musculoskeletal Ageing, held in January 2023, in which delegates analysed the key questions and research opportunities in the field of ECM ageing. We examine fundamental biological questions, enabling technologies, systems of study and emerging in vitro and in silico models, alongside consideration of the broader challenges facing the field.


Subject(s)
Aging , Extracellular Matrix , Animals , Humans , Extracellular Matrix/metabolism , United Kingdom
2.
Cell Commun Signal ; 21(1): 342, 2023 11 29.
Article in English | MEDLINE | ID: mdl-38031192

ABSTRACT

BACKGROUND: Despite improved patient outcome using tyrosine kinase inhibitors (TKIs), chronic myeloid leukaemia (CML) patients require life-long treatment due to leukaemic stem cell (LSC) persistence. LSCs reside in the bone marrow (BM) niche, which they modify to their advantage. The BM provides oncogene-independent signals to aid LSC cell survival and quiescence. The bone-morphogenetic pathway (BMP) is one pathway identified to be highly deregulated in CML, with high levels of BMP ligands detected in the BM, accompanied by CML stem and progenitor cells overexpressing BMP type 1 receptors- activin-like kinases (ALKs), especially in TKI resistant patients. Saracatinib (SC), a SRC/ABL1 dual inhibitor, inhibits the growth of CML cells resistant to the TKI imatinib (IM). Recent studies indicate that SC is also a potent ALK inhibitor and BMP antagonist. Here we investigate the efficacy of SC in overcoming CML BCR::ABL1 dependent and independent signals mediated by the BM niche both in 2D and 3D culture. METHODS: CML cells (K562 cell line and CML CD34+ primary cells) were treated with single or combination treatments of: IM, SC and the BMP receptors inhibitor dorsomorphin (DOR), with or without BMP4 stimulation in 2D (suspension) and 3D co-culture on HS5 stroma cell line and mesenchymal stem cells in AggreWell and microfluidic devices. Flow cytometry was performed to investigate apoptosis, cell cycle progression and proliferation, alongside colony assays following treatment. Proteins changes were validated by immunoblotting and transcriptional changes by Fluidigm multiplex qPCR. RESULTS: By targeting the BMP pathway, using specific inhibitors against ALKs in combination with SRC and ABL TKIs, we show an increase in apoptosis, altered cell cycle regulation, fewer cell divisions, and reduced numbers of CD34+ cells. Impairment of long-term proliferation and differentiation potential after combinatorial treatment also occurred. CONCLUSION: BMP signalling pathway is important for CML cell survival. Targeting SRC, ABL and ALK kinases is more effective than ABL inhibition alone, the combination efficacy importantly being demonstrated in both 2D and 3D cell cultures highlighting the need for combinatorial therapies in contrast to standard of care single agents. Our study provides justification to target multiple kinases in CML to combat LSC persistence.


Blood is made in the spongy inner most section of the bone, called the bone marrow. The bone marrow is where normal blood stem cells live that are responsible for producing the different blood cell types; white blood cells (fight infections), red blood cells (carrying oxygen around the body), platelets (blood clotting) and other cells which support this process. Chronic myeloid leukaemia (CML) is a type of blood cancer that starts in the bone marrow. CML occurs when a normal blood stem cell becomes damaged, forming a leukaemia stem cell (LSC), leading to blood cancer. LSCs multiply and generate many faulty cancerous white blood cells that do not work properly. Patients are treated with a drug called imatinib, which reduces the number of cancerous cells circulating in the body. In many cases, this treatment is not enough to cure the disease because the bone marrow protects the LSCs from the drug meaning patients must remain on long term treatment. This work has discovered one of the ways in which the bone marrow protects LSCs from treatments and has used this knowledge to test new drugs that stop this protection. Our findings show that by combining two drugs, one that overcomes this protection and one that directly targets the cancerous cells, we can destroy more of the LSCs. These findings are a step closer towards a cure for CML and could improve treatment for patients in the future. Video Abstract.


Subject(s)
Leukemia, Myelogenous, Chronic, BCR-ABL Positive , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy , Imatinib Mesylate/pharmacology , Imatinib Mesylate/therapeutic use , Bone Marrow/metabolism , Signal Transduction , Protein Kinase Inhibitors/pharmacology , Protein Kinase Inhibitors/therapeutic use , Apoptosis , Receptor Protein-Tyrosine Kinases/metabolism , Fusion Proteins, bcr-abl , Neoplastic Stem Cells/metabolism , Drug Resistance, Neoplasm
3.
Cell Mol Life Sci ; 79(7): 386, 2022 Jun 28.
Article in English | MEDLINE | ID: mdl-35760917

ABSTRACT

The gut microbiota plays a central role in regulating host metabolism. While substantial progress has been made in discerning how the microbiota influences host functions post birth and beyond, little is known about how key members of the maternal gut microbiota can influence feto-placental growth. Notably, in pregnant women, Bifidobacterium represents a key beneficial microbiota genus, with levels observed to increase across pregnancy. Here, using germ-free and specific-pathogen-free mice, we demonstrate that the bacterium Bifidobacterium breve UCC2003 modulates maternal body adaptations, placental structure and nutrient transporter capacity, with implications for fetal metabolism and growth. Maternal and placental metabolome were affected by maternal gut microbiota (i.e. acetate, formate and carnitine). Histological analysis of the placenta confirmed that Bifidobacterium modifies placental structure via changes in Igf2P0, Dlk1, Mapk1 and Mapk14 expression. Additionally, B. breve UCC2003, acting through Slc2a1 and Fatp1-4 transporters, was shown to restore fetal glycaemia and fetal growth in association with changes in the fetal hepatic transcriptome. Our work emphasizes the importance of the maternal gut microbiota on feto-placental development and sets a foundation for future research towards the use of probiotics during pregnancy.


Subject(s)
Gastrointestinal Microbiome , Placenta , Animals , Bifidobacterium , Female , Fetal Development , Humans , Mice , Nutrients , Placenta/metabolism , Pregnancy
4.
FASEB J ; 34(5): 7075-7088, 2020 05.
Article in English | MEDLINE | ID: mdl-32253791

ABSTRACT

The early life gut microbiota plays a crucial role in regulating and maintaining the intestinal barrier, with disturbances in these communities linked to dysregulated renewal and replenishment of intestinal epithelial cells. Here we sought to determine pathological cell shedding outcomes throughout the postnatal developmental period, and which host and microbial factors mediate these responses. Surprisingly, neonatal mice (Day 14 and 21) were highly refractory to induction of cell shedding after intraperitoneal administration of liposaccharide (LPS), with Day 29 mice showing strong pathological responses, more similar to those observed in adult mice. These differential responses were not linked to defects in the cellular mechanisms and pathways known to regulate cell shedding responses. When we profiled microbiota and metabolites, we observed significant alterations. Neonatal mice had high relative abundances of Streptococcus, Escherichia, and Enterococcus and increased primary bile acids. In contrast, older mice were dominated by Candidatus Arthromitus, Alistipes, and Lachnoclostridium, and had increased concentrations of SCFAs and methyamines. Antibiotic treatment of neonates restored LPS-induced small intestinal cell shedding, whereas adult fecal microbiota transplant alone had no effect. Our findings further support the importance of the early life window for microbiota-epithelial interactions in the presence of inflammatory stimuli and highlights areas for further investigation.


Subject(s)
Animals, Newborn/microbiology , Gastrointestinal Microbiome/physiology , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Animals , Animals, Newborn/metabolism , Anti-Bacterial Agents/administration & dosage , Bile Acids and Salts/metabolism , Epithelial Cells/metabolism , Epithelial Cells/pathology , Fecal Microbiota Transplantation , Female , Gastrointestinal Microbiome/drug effects , Gastrointestinal Microbiome/genetics , Host Microbial Interactions/drug effects , Host Microbial Interactions/physiology , Inflammation/metabolism , Inflammation/microbiology , Inflammation/pathology , Intestinal Mucosa/metabolism , Intestine, Small/metabolism , Intestine, Small/microbiology , Intestine, Small/pathology , Lipopolysaccharides/administration & dosage , Mice , Mice, Inbred C57BL , Signal Transduction
5.
Cell Biol Toxicol ; 37(6): 915-933, 2021 12.
Article in English | MEDLINE | ID: mdl-33420657

ABSTRACT

Mesenchymal stem cells represent an important resource, for bone regenerative medicine and therapeutic applications. This review focuses on new advancements and biophysical tools which exploit different physical and chemical markers of mesenchymal stem cell populations, to finely characterize phenotype changes along their osteogenic differentiation process. Special attention is paid to recently developed label-free methods, which allow monitoring cell populations with minimal invasiveness. Among them, quantitative phase imaging, suitable for single-cell morphometric analysis, and nanoindentation, functional to cellular biomechanics investigation. Moreover, the pool of ion channels expressed in cells during differentiation is discussed, with particular interest for calcium homoeostasis.Altogether, a biophysical perspective of osteogenesis is proposed, offering a valuable tool for the assessment of the cell stage, but also suggesting potential physiological links between apparently independent phenomena.


Subject(s)
Mesenchymal Stem Cells , Osteogenesis , Biomarkers , Cell Differentiation , Cells, Cultured
6.
Biochem J ; 477(17): 3349-3366, 2020 09 18.
Article in English | MEDLINE | ID: mdl-32941644

ABSTRACT

Twenty-five years have passed since the first clinical trial utilising mesenchymal stomal/stem cells (MSCs) in 1995. In this time academic research has grown our understanding of MSC biochemistry and our ability to manipulate these cells in vitro using chemical, biomaterial, and mechanical methods. Research has been emboldened by the promise that MSCs can treat illness and repair damaged tissues through their capacity for immunomodulation and differentiation. Since 1995, 31 therapeutic products containing MSCs and/or progenitors have reached the market with the level of in vitro manipulation varying significantly. In this review, we summarise existing therapeutic products containing MSCs or mesenchymal progenitor cells and examine the challenges faced when developing new therapeutic products. Successful progression to clinical trial, and ultimately market, requires a thorough understanding of these hurdles at the earliest stages of in vitro pre-clinical development. It is beneficial to understand the health economic benefit for a new product and the reimbursement potential within various healthcare systems. Pre-clinical studies should be selected to demonstrate efficacy and safety for the specific clinical indication in humans, to avoid duplication of effort and minimise animal usage. Early consideration should also be given to manufacturing: how cell manipulation methods will integrate into highly controlled workflows and how they will be scaled up to produce clinically relevant quantities of cells. Finally, we summarise the main regulatory pathways for these clinical products, which can help shape early therapeutic design and testing.


Subject(s)
Cell Differentiation , Cell Proliferation , Immunologic Factors , Immunomodulation , Mesenchymal Stem Cells/metabolism , Animals , Humans , Immunologic Factors/metabolism , Immunologic Factors/therapeutic use
7.
Lancet ; 393(10166): 51-60, 2019 01 05.
Article in English | MEDLINE | ID: mdl-30449623

ABSTRACT

BACKGROUND: The incidence of human papillomavirus (HPV)-positive oropharyngeal cancer, a disease affecting younger patients, is rapidly increasing. Cetuximab, an epidermal growth factor receptor inhibitor, has been proposed for treatment de-escalation in this setting to reduce the toxicity of standard cisplatin treatment, but no randomised evidence exists for the efficacy of this strategy. METHODS: We did an open-label randomised controlled phase 3 trial at 32 head and neck treatment centres in Ireland, the Netherlands, and the UK, in patients aged 18 years or older with HPV-positive low-risk oropharyngeal cancer (non-smokers or lifetime smokers with a smoking history of <10 pack-years). Eligible patients were randomly assigned (1:1) to receive, in addition to radiotherapy (70 Gy in 35 fractions), either intravenous cisplatin (100 mg/m2 on days 1, 22, and 43 of radiotherapy) or intravenous cetuximab (400 mg/m2 loading dose followed by seven weekly infusions of 250 mg/m2). The primary outcome was overall severe (grade 3-5) toxicity events at 24 months from the end of treatment. The primary outcome was assessed by intention-to-treat and per-protocol analyses. This trial is registered with the ISRCTN registry, number ISRCTN33522080. FINDINGS: Between Nov 12, 2012, and Oct 1, 2016, 334 patients were recruited (166 in the cisplatin group and 168 in the cetuximab group). Overall (acute and late) severe (grade 3-5) toxicity did not differ significantly between treatment groups at 24 months (mean number of events per patient 4·8 [95% CI 4·2-5·4] with cisplatin vs 4·8 [4·2-5·4] with cetuximab; p=0·98). At 24 months, overall all-grade toxicity did not differ significantly either (mean number of events per patient 29·2 [95% CI 27·3-31·0] with cisplatin vs 30·1 [28·3-31·9] with cetuximab; p=0·49). However, there was a significant difference between cisplatin and cetuximab in 2-year overall survival (97·5% vs 89·4%, hazard ratio 5·0 [95% CI 1·7-14·7]; p=0·001) and 2-year recurrence (6·0% vs 16·1%, 3·4 [1·6-7·2]; p=0·0007). INTERPRETATION: Compared with the standard cisplatin regimen, cetuximab showed no benefit in terms of reduced toxicity, but instead showed significant detriment in terms of tumour control. Cisplatin and radiotherapy should be used as the standard of care for HPV-positive low-risk patients who are able to tolerate cisplatin. FUNDING: Cancer Research UK.


Subject(s)
Antineoplastic Agents/therapeutic use , Cetuximab/therapeutic use , Cisplatin/therapeutic use , Oropharyngeal Neoplasms/therapy , Squamous Cell Carcinoma of Head and Neck/therapy , Acute Disease , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/adverse effects , Cetuximab/administration & dosage , Cetuximab/adverse effects , Chemoradiotherapy/adverse effects , Chemoradiotherapy/methods , Cisplatin/administration & dosage , Cisplatin/adverse effects , Drug Administration Schedule , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Neoplasm Staging , Oropharyngeal Neoplasms/pathology , Oropharyngeal Neoplasms/virology , Papillomavirus Infections/complications , Radiotherapy, Intensity-Modulated/adverse effects , Radiotherapy, Intensity-Modulated/methods , Risk Assessment , Squamous Cell Carcinoma of Head and Neck/pathology , Squamous Cell Carcinoma of Head and Neck/virology , Treatment Outcome
8.
Philos Trans A Math Phys Eng Sci ; 376(2120)2018 May 28.
Article in English | MEDLINE | ID: mdl-29661978

ABSTRACT

Mechanical signals are ubiquitous in our everyday life and the process of converting these mechanical signals into a biological signalling response is known as mechanotransduction. Our understanding of mechanotransduction, and its contribution to vital cellular responses, is a rapidly expanding field of research involving complex processes that are still not clearly understood. The use of mechanical vibration as a stimulus of mechanotransduction, including variation of frequency and amplitude, allows an alternative method to control specific cell behaviour without chemical stimulation (e.g. growth factors). Chemical-independent control of cell behaviour could be highly advantageous for fields including drug discovery and clinical tissue engineering. In this review, a novel technique is described based on nanoscale sinusoidal vibration. Using finite-element analysis in conjunction with laser interferometry, techniques that are used within the field of gravitational wave detection, optimization of apparatus design and calibration of vibration application have been performed. We further discuss the application of nanovibrational stimulation, or 'nanokicking', to eukaryotic and prokaryotic cells including the differentiation of mesenchymal stem cells towards an osteoblast cell lineage. Mechanotransductive mechanisms are discussed including mediation through the Rho-A kinase signalling pathway. Optimization of this technique was first performed in two-dimensional culture using a simple vibration platform with an optimal frequency and amplitude of 1 kHz and 22 nm. A novel bioreactor was developed to scale up cell production, with recent research demonstrating that mesenchymal stem cell differentiation can be efficiently triggered in soft gel constructs. This important step provides first evidence that clinically relevant (three-dimensional) volumes of osteoblasts can be produced for the purpose of bone grafting, without complex scaffolds and/or chemical induction. Initial findings have shown that nanovibrational stimulation can also reduce biofilm formation in a number of clinically relevant bacteria. This demonstrates additional utility of the bioreactor to investigate mechanotransduction in other fields of research.This article is part of a discussion meeting issue 'The promises of gravitational-wave astronomy'.

9.
Nanomedicine ; 14(7): 2455-2464, 2018 10.
Article in English | MEDLINE | ID: mdl-28552647

ABSTRACT

Regulation of cell behavior in response to nanoscale features has been the focus of much research in recent years and the successful generation of nanoscale features capable of mimicking the natural nanoscale interface has been of great interest in the field of biomaterials research. In this review, we discuss relevant nanofabrication techniques and how they are combined with bioengineering applications to mimic the natural extracellular matrix (ECM) and create valuable nanoscale interfaces.


Subject(s)
Biocompatible Materials/chemistry , Biomimetics , Cell Adhesion , Extracellular Matrix/chemistry , Nanostructures/chemistry , Animals , Humans
10.
Langmuir ; 32(3): 800-9, 2016 Jan 26.
Article in English | MEDLINE | ID: mdl-26715432

ABSTRACT

Cells, by interacting with surfaces indirectly through a layer of extracellular matrix proteins, can respond to a variety of physical properties, such as topography or stiffness. Polymer surface mobility is another physical property that is less well understood but has been indicated to hold the potential to modulate cell behavior. Polymer mobility is related to the glass-transition temperature (Tg) of the system, the point at which a polymer transitions from an amorphous solid to a more liquid-like state. This work shows that changes in polymer mobility translate to interfacial mobility of extracellular matrix proteins adsorbed on the material surface. This study has utilized a family of polyalkyl acrylates with similar chemistry but different degrees of mobility, obtained through increasing length of the side chain. These materials are used, in conjunction with fluorescent fibronectin, to determine the mobility of this interfacial layer of protein that constitutes the initial cell-material interface. Furthermore, the extent of fibronectin domain availability (III9, III10, - the integrin binding site), cell-mediated reorganization, and cell differentiation was also determined. A nonmonotonic dependence of fibronectin mobility on polymer surface mobility was observed, with a similar trend noted in cell-mediated reorganization of the protein layer by L929 fibroblasts. The availability of the integrin-binding site was higher on the more mobile surfaces, where a similar organization of the protein into networks at the material interface was observed. Finally, differentiation of C2C12 myoblasts was seen to be highly sensitive to surface mobility upon inhibition of cell contractility. Altogether, these findings show that polymer mobility is a subtle influence that translates to the cell/material interface through the protein layer to alter the biological activity of the surface.


Subject(s)
Acrylates/chemistry , Extracellular Matrix Proteins/chemistry , Fibronectins/chemistry , Integrins/chemistry , Animals , Cell Adhesion , Cell Line , Fibroblasts/chemistry , Fibroblasts/cytology , Fluorescein-5-isothiocyanate/chemistry , Fluorescent Dyes/chemistry , Mice , Myoblasts/chemistry , Myoblasts/cytology , Phase Transition , Protein Binding , Protein Transport , Surface Properties , Transition Temperature
11.
Nat Mater ; 13(6): 558-69, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24845995

ABSTRACT

Stem cells respond to nanoscale surface features, with changes in cell growth and differentiation mediated by alterations in cell adhesion. The interaction of nanotopographical features with integrin receptors in the cells' focal adhesions alters how the cells adhere to materials surfaces, and defines cell fate through changes in both cell biochemistry and cell morphology. In this Review, we discuss how cell adhesions interact with nanotopography, and we provide insight as to how materials scientists can exploit these interactions to direct stem cell fate and to understand how the behaviour of stem cells in their niche can be controlled. We expect knowledge gained from the study of cell-nanotopography interactions to accelerate the development of next-generation stem cell culture materials and implant interfaces, and to fuel discovery of stem cell therapeutics to support regenerative therapies.


Subject(s)
Extracellular Matrix/chemistry , Focal Adhesions , Integrins/chemistry , Stem Cells/metabolism , Cell Adhesion , Extracellular Matrix/metabolism , Humans , Integrins/metabolism , Stem Cells/cytology
12.
J Cell Biochem ; 115(2): 380-90, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24123223

ABSTRACT

There is a rapidly growing body of literature on the effects of topography and critically, nanotopography on cell adhesion, apoptosis and differentiation. Understanding the effects of nanotopography on cell adhesion and morphology and the consequences of cell shape changes in the nucleus, and consequently, gene expression offers new approaches to the elucidation and potential control of stem cell differentiation. In the current study we have used molecular approaches in combination with immunohistology and transcript analysis to understand the role of nanotopography on mesenchymal stem cell morphology and phenotype. Results demonstrate large changes in cell adhesion, nucleus and lamin morphologies in response to the different nanotopographies. Furthermore, these changes relate to alterations in packing of chromosome territories within the interphase nucleus. This, in turn, leads to changes in transcription factor activity and functional (phenotypical) signalling including cell metabolism. Nanotopography provides a useful, non-invasive tool for studying cellular mechanotransduction, gene and protein expression patterns, through effects on cell morphology. The different nanotopographies examined, result in different morphological changes in the cyto- and nucleo-skeleton. We propose that both indirect (biochemical) and direct (mechanical) signalling are important in these early stages of regulating stem cell fate as a consequence of altered metabolic changes and altered phenotype. The current studies provide new insight on cell-surface interactions and enhance our understanding of the modulation of stem cell differentiation with significant potential application in regenerative medicine.


Subject(s)
Cell Differentiation/genetics , Cell Nucleus/ultrastructure , Cell Shape/genetics , Mesenchymal Stem Cells/ultrastructure , Apoptosis/genetics , Cell Adhesion/genetics , Cell Nucleus/genetics , Gene Expression Regulation , Humans , Mesenchymal Stem Cells/metabolism , Phenotype , Regenerative Medicine , Signal Transduction
14.
Nano Lett ; 13(2): 570-6, 2013 Feb 13.
Article in English | MEDLINE | ID: mdl-23252684

ABSTRACT

The function and fate of cells is influenced by many different factors, one of which is surface topography of the support culture substrate. Systematic studies of nanotopography and cell response have typically been limited to single cell types and a small set of topographical variations. Here, we show a radical expansion of experimental throughput using automated detection, measurement, and classification of co-cultured cells on a nanopillar array where feature height changes continuously from planar to 250 nm over 9 mm. Individual cells are identified and characterized by more than 200 descriptors, which are used to construct a set of rules for label-free segmentation into individual cell types. Using this approach we can achieve label-free segmentation with 84% confidence across large image data sets and suggest optimized surface parameters for nanostructuring of implant devices such as vascular stents.


Subject(s)
Cell Tracking/methods , Endothelial Cells/cytology , Fibroblasts/cytology , Nanostructures/chemistry , Nanotechnology/methods , Cell Tracking/instrumentation , Coculture Techniques , Fluorescence , Humans , Nanotechnology/instrumentation
15.
Exp Hematol ; 135: 104232, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38729553

ABSTRACT

The bone marrow (BM) niche is a complex microenvironment that provides the signals required for regulation of hematopoietic stem cells (HSCs) and the process of hematopoiesis they are responsible for. Bioengineered models of the BM niche incorporate various elements of the in vivo BM microenvironment, including cellular components, soluble factors, a three-dimensional environment, mechanical stimulation of included cells, and perfusion. Recent advances in the bioengineering field have resulted in a spate of new models that shed light on BM function and are approaching precise imitation of the BM niche. These models promise to improve our understanding of the in vivo microenvironment in health and disease. They also aim to serve as platforms for HSC manipulation or as preclinical models for screening novel therapies for BM-associated disorders and diseases.

16.
Biomater Adv ; 160: 213861, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38663159

ABSTRACT

Novel strategies employing mechano-transducing materials eliciting biological outcomes have recently emerged for controlling cellular behaviour. Targeted cellular responses are achieved by manipulating physical, chemical, or biochemical modification of material properties. Advances in techniques such as nanopatterning, chemical modification, biochemical molecule embedding, force-tuneable materials, and artificial extracellular matrices are helping understand cellular mechanotransduction. Collectively, these strategies manipulate cellular sensing and regulate signalling cascades including focal adhesions, YAP-TAZ transcription factors, and multiple osteogenic pathways. In this minireview, we are providing a summary of the influence that these materials, particularly titanium-based orthopaedic materials, have on cells. We also highlight recent complementary methodological developments including, but not limited to, the use of metabolomics for identification of active biomolecules that drive cellular differentiation.


Subject(s)
Mechanotransduction, Cellular , Osteogenesis , Osteogenesis/physiology , Humans , Titanium/chemistry , Animals , Cell Differentiation , Surface Properties , Biocompatible Materials/chemistry , Extracellular Matrix/metabolism , Extracellular Matrix/physiology , Extracellular Matrix/chemistry
17.
Adv Mater ; 36(23): e2310789, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38253339

ABSTRACT

Conventional osteogenic platforms utilize active growth factors to repair bone defects that are extensive in size, but they can adversely affect patient health. Here, an unconventional osteogenic platform is reported that functions by promoting capture of inactive osteogenic growth factor molecules to the site of cell growth for subsequent integrin-mediated activation, using a recombinant fragment of latent transforming growth factor beta-binding protein-1 (rLTBP1). It is shown that rLTBP1 binds to the growth-factor- and integrin-binding domains of fibronectin on poly(ethyl acrylate) surfaces, which immobilizes rLTBP1 and promotes the binding of latency associated peptide (LAP), within which inactive transforming growth factor beta 1 (TGF-ß1) is bound. rLTBP1 facilitates the interaction of LAP with integrin ß1 and the subsequent mechanically driven release of TGF-ß1 to stimulate canonical TGF-ß1 signaling, activating osteogenic marker expression in vitro and complete regeneration of a critical-sized bone defect in vivo.


Subject(s)
Osteogenesis , Transforming Growth Factor beta1 , Animals , Humans , Transforming Growth Factor beta1/metabolism , Fibronectins/metabolism , Fibronectins/chemistry , Latent TGF-beta Binding Proteins/metabolism , Latent TGF-beta Binding Proteins/chemistry , Bone Regeneration , Surface Properties , Integrins/metabolism , Protein Binding , Integrin beta1/metabolism , Signal Transduction
18.
Acta Biomater ; 180: 154-170, 2024 05.
Article in English | MEDLINE | ID: mdl-38621600

ABSTRACT

Bacterial infection remains a significant problem associated with orthopaedic surgeries leading to surgical site infection (SSI). This unmet medical need can become an even greater complication when surgery is due to malignant bone tumor. In the present study, we evaluated in vitro titanium (Ti) implants subjected to gallium (Ga) and silver (Ag)-doped thermochemical treatment as strategy to prevent SSI and improve osteointegration in bone defects caused by diseases such as osteoporosis, bone tumor, or bone metastasis. Firstly, as Ga has been reported to be an osteoinductive and anti-resorptive agent, its performance in the mixture was proved by studying human mesenchymal stem cells (hMSC) and pre-osteoclasts (RAW264.7) behaviour. Then, the antibacterial potential provided by Ag was assessed by resembling "The Race for the Surface" between hMSC and Pseudomonas aeruginosa in two co-culture methods. Moreover, the presence of quorum sensing molecules in the co-culture was evaluated. The results highlighted the suitability of the mixture to induce osteodifferentiation and reduce osteoclastogenesis in vitro. Furthermore, the GaAg surface promoted strong survival rate and retained osteoinduction potential of hMSCs even after bacterial inoculation. Therefore, GaAg-modified titanium may be an ideal candidate to repair bone defects caused by excessive bone resorption, in addition to preventing SSI. STATEMENT OF SIGNIFICANCE: This article provides important insights into titanium for fractures caused by osteoporosis or bone metastases with high incidence in surgical site infection (SSI) because in this situation bacterial infection can become a major disaster. In order to solve this unmet medical need, we propose a titanium implant modified with gallium and silver to improve osteointegration, reduce bone resorption and avoid bacterial infection. For that aim, we study osteoblast and osteoclast behavior with the main novelty focused on the antibacterial evaluation. In this work, we recreate "the race for the surface" in long-term experiments and study bacterial virulence factors (quorum sensing). Therefore, we believe that our article could be of great interest, providing a great impact on future orthopedic applications.


Subject(s)
Coculture Techniques , Gallium , Mesenchymal Stem Cells , Osteogenesis , Pseudomonas aeruginosa , Silver , Titanium , Titanium/chemistry , Titanium/pharmacology , Silver/pharmacology , Silver/chemistry , Humans , Gallium/pharmacology , Gallium/chemistry , Mice , Mesenchymal Stem Cells/drug effects , Animals , Osteogenesis/drug effects , Pseudomonas aeruginosa/drug effects , Bone Resorption/pathology , Surface Properties , RAW 264.7 Cells , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bacterial Infections/prevention & control
19.
Biomater Adv ; 158: 213766, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38232578

ABSTRACT

Medical implant-associated infections pose a significant challenge to modern medicine, with aseptic loosening and bacterial infiltration being the primary causes of implant failure. While nanostructured surfaces have demonstrated promising antibacterial properties, the translation of their efficacy from 2D to 3D substrates remains a challenge. Here, we used scalable alkaline etching to fabricate nanospike and nanonetwork topologies on 2D and laser powder-bed fusion printed 3D titanium. The fabricated surfaces were compared with regard to their antibacterial properties against Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and mesenchymal stromal cell responses with and without the presence of bacteria. Finite elemental analysis assessed the mechanical properties and permeability of the 3D substrate. Our findings suggest that 3D nanostructured surfaces have potential to both prevent implant infections and allow host cell integration. This work represents a significant step towards developing effective and scalable fabrication methods on 3D substrates with consistent and reproducible antibacterial activity, with important implications for the future of medical implant technology.


Subject(s)
Bacterial Adhesion , Titanium , Titanium/pharmacology , Coculture Techniques , Surface Properties , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Bacteria
20.
Article in English | MEDLINE | ID: mdl-38888932

ABSTRACT

Protein materials are versatile tools in diverse biomedical fields. Among them, artificial secretory granules (SGs), mimicking those from the endocrine system, act as mechanically stable reservoirs for the sustained release of proteins as oligomeric functional nanoparticles. Only validated in oncology, the physicochemical properties of SGs, along with their combined drug-releasing and scaffolding abilities, make them suitable as smart topographies in regenerative medicine for the prolonged delivery of growth factors (GFs). Thus, considering the need for novel, safe, and cost-effective materials to present GFs, in this study, we aimed to biofabricate a protein platform combining both endocrine-like and extracellular matrix fibronectin-derived (ECM-FN) systems. This approach is based on the sustained delivery of a nanostructured histidine-tagged version of human fibroblast growth factor 2. The GF is presented onto polymeric surfaces, interacting with FN to spontaneously generate nanonetworks that absorb and present the GF in the solid state, to modulate mesenchymal stromal cell (MSC) behavior. The results show that SGs-based topographies trigger high rates of MSCs proliferation while preventing differentiation. While this could be useful in cell therapy manufacture demanding large numbers of unspecialized MSCs, it fully validates the hybrid platform as a convenient setup for the design of biologically active hybrid surfaces and in tissue engineering for the controlled manipulation of mammalian cell growth.

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