ABSTRACT
BACKGROUND: Public involvement and engagement (PI&E) is increasingly recognised as an important component of research. It can offer valuable insights from those with experiential knowledge to improve research quality, relevance, and reach. Similarly, schools are ever more common sites for health research and, more recently, PI&E. However, 'gold-standard' practice is yet to be established, and activities/approaches remain underreported. As a result, knowledge can remain localised or lost. Diversity and inclusion also remains a challenge. METHODS: This protocol has been informed by UK national guidance, evidence-based frameworks and available implementation literature. It describes both rationale and approach to conducting PI&E activities within a secondary school context. Activities are designed to be engaging, safe and accessible to young people with diverse experiences, with scope to be iteratively developed in line with public collaborator preference. DISCUSSION: Young people should be architects of their involvement and engagement. Ongoing appraisal and transparency of approaches to PI&E in school settings is crucial. Expected challenges of implementing this protocol include facilitating a safe space for the discussion of sensitive topics, absence and attrition, recruiting students with a diverse range of experiences, and potential knowledge and capacity barriers of both facilitator and contributors. Activities to mitigate these risks are suggested and explored.
Schools are increasingly becoming hubs for health research. However, there is a lack of knowledge about how researchers, schools and students can best work together to shape the studies we do. This is a problem as, in the world of research, involving those with first hand experiences (public collaborators) in the research process is seen as crucial.This protocol outlines our plan for conducting public involvement and engagement activities in secondary schools. It is based on national guidance and existing evidence. The goal is to make these activities interesting, safe, and accessible to young people with diverse experiences. The approach is designed to be flexible, allowing adjustments based on the preferences of the public collaborators.We acknowledge that we may face some difficulties with our approach. This may include challenges in recruitment of public collaborators, dealing with absence and attrition, and creating a safe space for discussing sensitive topics. Collaborators from both academic and lived backgrounds may also experience barriers in knowledge and capacity. This protocol suggests activities to address and overcome these challenges. We emphasise the need for ongoing evaluation and transparency in public involvement and engagement approaches within school settings.
ABSTRACT
To investigate how host and pathogen diversity govern immunity against Mycobacterium tuberculosis (Mtb), we performed a large-scale screen of vaccine-mediated protection against aerosol Mtb infection using three inbred mouse strains [C57BL/6 (B6), C3HeB/FeJ (C3H), Balb/c x 129/SvJ (C129F1)] and three Mtb strains (H37Rv, CDC1551, SA161) representing two lineages and distinct virulence properties. We compared three protective modalities, all of which involve inoculation with live mycobacteria: Bacillus Calmette-Guérin (BCG), the only approved TB vaccine, delivered either subcutaneously or intravenously, and concomitant Mtb infection (CoMtb), a model of pre-existing immunity in which a low-level Mtb infection is established in the cervical lymph node following intradermal inoculation. We examined lung bacterial burdens at early (Day 28) and late (Day 98) time points after aerosol Mtb challenge and histopathology at Day 98. We observed substantial heterogeneity in the reduction of bacterial load afforded by these modalities at Day 28 across the combinations and noted a strong positive correlation between bacterial burden in unvaccinated mice and the degree of protection afforded by vaccination. Although we observed variation in the degree of reduction in bacterial burdens across the nine mouse/bacterium strain combinations, virtually all protective modalities performed similarly for a given strain-strain combination. We also noted dramatic variation in histopathology changes driven by both host and bacterial genetic backgrounds. Vaccination improved pathology scores for all infections except CDC1551. However, the most dramatic impact of vaccination on lesion development occurred for the C3H-SA161 combination, where vaccination entirely abrogated the development of the large necrotic lesions that arise in unvaccinated mice. In conclusion, we find that substantial TB heterogeneity can be recapitulated by introducing variability in both host and bacterial genetics, resulting in changes in vaccine-mediated protection as measured both by bacterial burden as well as histopathology. These differences can be harnessed in future studies to identify immune correlates of vaccine efficacy.
Subject(s)
Mycobacterium tuberculosis , Animals , Mycobacterium tuberculosis/immunology , Mycobacterium tuberculosis/genetics , Mice , Genetic Variation , Female , Tuberculosis/prevention & control , Tuberculosis/immunology , Tuberculosis/microbiology , Tuberculosis Vaccines/immunology , Mice, Inbred C57BL , Mice, Inbred BALB C , Host-Pathogen Interactions/immunology , BCG Vaccine/immunology , Lung/microbiology , Lung/pathology , Lung/immunology , Disease Models, Animal , Bacterial Load , VaccinationABSTRACT
Minerals play a vital role, working synergistically with enzymes and other cofactors to regulate physiological functions including tissue healing and regeneration. The bioactive characteristics of mineral-based nanomaterials can be harnessed to facilitate in situ tissue regeneration by attracting endogenous progenitor and stem cells and subsequently directing tissue-specific differentiation. Here, cellular responses of human mesenchymal stem/stromal cells to traditional bioactive mineral-based nanomaterials, such as hydroxyapatite, whitlockite, silicon-dioxide, and the emerging synthetic 2D nanosilicates are investigated. Transcriptome sequencing is utilized to probe the cellular response and determine the significantly affected signaling pathways due to exposure to these inorganic nanomaterials. Transcriptome profiles of stem cells treated with nanosilicates reveals a stabilized skeletal progenitor state suggestive of endochondral differentiation. This observation is bolstered by enhanced deposition of matrix mineralization in nanosilicate treated stem cells compared to control or other treatments. Specifically, use of 2D nanosilicates directs osteogenic differentiation of stem cells via activation of bone morphogenetic proteins and hypoxia-inducible factor 1-alpha signaling pathway. This study provides insight into impact of nanomaterials on cellular gene expression profile and predicts downstream effects of nanomaterial induction of endochondral differentiation.
Subject(s)
Biocompatible Materials , Cell Differentiation , Mesenchymal Stem Cells , Transcriptome , Humans , Transcriptome/genetics , Transcriptome/drug effects , Cell Differentiation/drug effects , Cell Differentiation/genetics , Mesenchymal Stem Cells/drug effects , Mesenchymal Stem Cells/metabolism , Biocompatible Materials/pharmacology , Osteogenesis/drug effects , Osteogenesis/genetics , Cells, Cultured , Nanostructures , Gene Expression Profiling/methodsABSTRACT
Despite widespread immunization with Bacille-Calmette-Guérin (BCG), the only currently licensed tuberculosis (TB) vaccine, TB remains a leading cause of mortality globally. There are many TB vaccine candidates in the developmental pipeline, but the lack of a robust animal model to assess vaccine efficacy has hindered our ability to prioritize candidates for human clinical trials. Here we use a murine ultra-low dose (ULD) Mycobacterium tuberculosis (Mtb) challenge model to assess protection conferred by BCG vaccination. We show that BCG confers a reduction in lung bacterial burdens that is more durable than that observed after conventional dose challenge, curbs Mtb dissemination to the contralateral lung, and, in a small percentage of mice, prevents detectable infection. These findings are consistent with the ability of human BCG vaccination to mediate protection, particularly against disseminated disease, in specific human populations and clinical settings. Overall, our findings demonstrate that the ultra-low dose Mtb infection model can measure distinct parameters of immune protection that cannot be assessed in conventional dose murine infection models and could provide an improved platform for TB vaccine testing.
Subject(s)
Mycobacterium bovis , Mycobacterium tuberculosis , Tuberculosis Vaccines , Animals , Mice , Humans , BCG Vaccine , Disease Models, Animal , VaccinationABSTRACT
BACKGROUND: The high volume and pace of research has posed challenges to researchers, policymakers and practitioners wanting to understand the overall impact of the pandemic on children and young people's mental health. We aimed to search for and review the evidence from epidemiological studies to answer the question: how has mental health changed in the general population of children and young people? METHODS: Four databases (Medline, CINAHL, EMBASE and PsychINFO) were searched in October 2021, with searches updated in February 2022. We aimed to identify studies of children or adolescents with a mean age of 18 years or younger at baseline, that reported change on a validated mental health measure from prepandemic to during the pandemic. Abstracts and full texts were double-screened against inclusion criteria and quality assessed using a risk of bias tool. Studies were narratively synthesised, and meta-analyses were performed where studies were sufficiently similar. RESULTS: 6917 records were identified, and 51 studies included in the review. Only four studies had a rating of high quality. Studies were highly diverse in terms of design, setting, timing in relation to the pandemic, population, length of follow-up and choice of measure. Methodological heterogeneity limited the potential to conduct meta-analyses across studies. Whilst the evidence suggested a slight deterioration on some measures, overall, the findings were mixed, with no clear pattern emerging. CONCLUSIONS: Our findings highlight the need for a more harmonised approach to research in this field. Despite the sometimes-inconsistent results of our included studies, the evidence supports existing concerns about the impact of Covid-19 on children's mental health and on services for this group, given that even small changes can have a significant impact on provision at population level. Children and young people must be prioritised in pandemic recovery, and explicitly considered in planning for any future pandemic response.
Subject(s)
COVID-19 , Mental Disorders , Adolescent , Humans , Child , Pandemics , Mental HealthABSTRACT
BACKGROUND: Exclusion from school is a disciplinary tool with an increasingly recognised relationship to poor mental health among children and young people. We explored the relationship between mental health and school exclusion for a cohort of children and young people receiving one to one counselling. METHOD: We analysed routinely collected data from a diverse UK sample of children and young people aged between four and 16 years old and receiving school-based counselling (n = 6712 students from 308 primary and 61 secondary schools). Fixed period school exclusion rates (number of sessions) were compared between the academic year before and the academic year in which the child attended counselling. Mental health (Strengths and Difficulties Questionnaire) was compared at baseline and at the end of the intervention (after between 16-22 counselling sessions depending on the phase of education). RESULTS: Despite more complex and severe initial difficulties, and facing greater adversity, children and young people who experienced school exclusion prior to counselling demonstrated a significant reduction in subsequent sessions of school exclusion in the academic year that the counselling took place (from two full school weeks to half a school week). Moreover, over 74% of the students had fewer reported exclusions and more than half (56.14%) did not have any further subsequent exclusions. They also had better mental health measured by the teacher reported SDQ (pre-intervention M = 18.94, SD = 6.83 vs. postintervention M = 15.67, SD = 7.56, t(310) = 8.23, p < .001) or by the parents (pre-intervention M = 18.09, SD = 6.42 vs. postintervention M = 14.0, SD = 6.99, t(171) = 7.71, p < .001). CONCLUSIONS: School-based mental health interventions may positively influence educational engagement as well as mental health. Providers should, therefore, monitor both to explore the impact of their interventions. The identification of poor mental health may alter staff perceptions and management of challenging pupils, which future studies should explore.
Subject(s)
Counseling , Schools , Humans , Child , Adolescent , Child, Preschool , Mental Health , Educational Status , Outcome Assessment, Health CareABSTRACT
OBJECTIVES: Attention deficit hyperactivity disorder (ADHD) is a prevalent childhood disorder, but often goes unrecognised and untreated. To improve access to services, accurate predictions of populations at high risk of ADHD are needed for effective resource allocation. Using a unique linked health and education data resource, we examined how machine learning (ML) approaches can predict risk of ADHD. DESIGN: Retrospective population cohort study. SETTING: South London (2007-2013). PARTICIPANTS: n=56 258 pupils with linked education and health data. PRIMARY OUTCOME MEASURES: Using area under the curve (AUC), we compared the predictive accuracy of four ML models and one neural network for ADHD diagnosis. Ethnic group and language biases were weighted using a fair pre-processing algorithm. RESULTS: Random forest and logistic regression prediction models provided the highest predictive accuracy for ADHD in population samples (AUC 0.86 and 0.86, respectively) and clinical samples (AUC 0.72 and 0.70). Precision-recall curve analyses were less favourable. Sociodemographic biases were effectively reduced by a fair pre-processing algorithm without loss of accuracy. CONCLUSIONS: ML approaches using linked routinely collected education and health data offer accurate, low-cost and scalable prediction models of ADHD. These approaches could help identify areas of need and inform resource allocation. Introducing 'fairness weighting' attenuates some sociodemographic biases which would otherwise underestimate ADHD risk within minority groups.
Subject(s)
Attention Deficit Disorder with Hyperactivity , Humans , Child , Attention Deficit Disorder with Hyperactivity/diagnosis , Attention Deficit Disorder with Hyperactivity/epidemiology , Retrospective Studies , Cohort Studies , Schools , Delivery of Health Care , Machine LearningABSTRACT
Bioactive materials harness the body's innate regenerative potential by directing endogenous progenitor cells to facilitate tissue repair. Dissolution products of inorganic biomaterials provide unique biomolecular signaling for tissue-specific differentiation. Inorganic ions (minerals) are vital to biological processes and play crucial roles in regulating gene expression patterns and directing cellular fate. However, mechanisms by which ionic dissolution products affect cellular differentiation are not well characterized. We demonstrate the role of the inorganic biomaterial synthetic two-dimensional nanosilicates and its ionic dissolution products on human mesenchymal stem cell differentiation. We use whole-transcriptome sequencing (RNA-sequencing) to characterize the contribution of nanosilicates and its ionic dissolution products on endochondral differentiation. Our study highlights the modulatory role of ions in stem cell transcriptome dynamics by regulating lineage-specific gene expression patterns. This work paves the way for leveraging biochemical characteristics of inorganic biomaterials to direct cellular processes and promote in situ tissue regeneration.
Subject(s)
Biocompatible Materials , Stem Cells , Biocompatible Materials/chemistry , Cell Differentiation/genetics , Humans , Ions , Stem Cells/metabolism , TranscriptomeABSTRACT
BACKGROUND: Depression and anxiety are major public health concerns among adolescents. Computerized cognitive behavioral therapy (cCBT) has emerged as a potential intervention, but its efficacy in adolescents remains unestablished. OBJECTIVE: This review aimed to systematically review and meta-analyze findings on the efficacy of cCBT for the treatment of adolescent depression and anxiety. METHODS: Embase, PsycINFO, and Ovid MEDLINE were systematically searched for randomized controlled trials in English, which investigated the efficacy of cCBT for reducing self-reported depression or anxiety in adolescents aged 11 to 19 years. Titles, abstracts, and full texts were screened for eligibility by 2 independent researchers (TB and LC). A random-effects meta-analysis was conducted to pool the effects of cCBT on depression and anxiety symptom scores compared with the control groups. Study quality was assessed using the Cochrane Collaboration Risk of Bias tool. RESULTS: A total of 16 randomized controlled trials were eligible for inclusion in this review, of which 13 (81%) were included in the meta-analysis. The quality of the studies was mixed, with 5 (31%) studies rated as good overall, 2 (13%) rated as fair, and 9 (56%) rated as poor. Small but statistically significant effects of cCBT were detected, with cCBT conditions showing lower symptom scores at follow-up compared with control conditions for both anxiety (standardized mean difference -0.21, 95% CI -0.33 to -0.09; I2=36.2%) and depression (standardized mean difference -0.23, 95% CI -0.39 to -0.07; I2=59.5%). Secondary analyses suggested that cCBT may be comparable with alternative, active interventions (such as face-to-face therapy or treatment as usual). CONCLUSIONS: This meta-analysis reinforces the efficacy of cCBT for the treatment of anxiety and depression and is the first to examine this exclusively in adolescents. Future research could aim to identify the active components of these interventions toward optimizing their development and increasing the feasibility and acceptability of cCBT in this age group. TRIAL REGISTRATION: PROSPERO CRD42019141941; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=141941.
Subject(s)
Cognitive Behavioral Therapy , Depression , Adolescent , Anxiety/therapy , Anxiety Disorders/therapy , Depression/therapy , HumansABSTRACT
Following COVID-19, there has been increasing concern about the well-being of children and young people across the United Kingdom; however, our major problem is the lack of robust data. We discuss emerging research capturing the impact of restrictions and experiences of COVID-19 on children and young people. We suggest further and more detailed analysis is urgently required to inform an evidence-based response. We conclude that although most of the UK's kids are probably OK, it is essential that those who are in need of support receive timely and informed intervention.
Subject(s)
Mental Disorders/epidemiology , Mental Health , Neurodevelopmental Disorders/epidemiology , Psychology, Adolescent , Adolescent , Child , Child, Preschool , Family , Family Conflict , Female , Food Supply , Humans , Male , Schools , United KingdomABSTRACT
The Covid-19 crisis necessitated rapid adoption of remote consultations across National Health Service (NHS) child and adolescent mental health services (CAMHS). This study aimed to understand practitioners' experiences of rapid implementation of remote consultations across CAMHS in one NHS trust in the east of England. Data were collected through a brief questionnaire documenting clinicians' experiences following remote delivery of services. The questionnaire began before 'lockdown' and focused on assessment consultations (n = 102) as part of a planned move to virtual assessment. As the roll-out of remote consultations was extended at lockdown, we extended the questionnaire to include all remote clinical contacts (n = 202). Despite high levels of initial concern, clinicians' reports were positive overall; importantly, however, their experiences varied by team. When restrictions on face-to-face working are lifted, a blended approach of remote and face-to-face service delivery is recommended to optimise access and capacity while retaining effective and safe care.
ABSTRACT
BACKGROUND: Mobile health apps are increasingly available and used in a clinical context to monitor young people's mood and mental health. Despite the benefits of accessibility and cost-effectiveness, consumer engagement remains a hurdle for uptake and continued use. Hundreds of mood-monitoring apps are publicly available to young people on app stores; however, few studies have examined consumer perspectives. App store reviews held on Google and Apple platforms provide a large, rich source of naturally generated, publicly available user reviews. Although commercial developers use these data to modify and improve their apps, to date, there has been very little in-depth evaluation of app store user reviews within scientific research, and our current understanding of what makes apps engaging and valuable to young people is limited. OBJECTIVE: This study aims to gain a better understanding of what app users consider useful to encourage frequent and prolonged use of mood-monitoring apps appropriate for young people. METHODS: A systematic approach was applied to the selection of apps and reviews. We identified mood-monitoring apps (n=53) by a combination of automated application programming interface (API) methods. We only included apps appropriate for young people based on app store age categories (apps available to those younger than 18 years). We subsequently downloaded all available user reviews via API data scraping methods and selected a representative subsample of reviews (n=1803) for manual qualitative content analysis. RESULTS: The qualitative content analysis revealed 8 main themes: accessibility (34%), flexibility (21%), recording and representation of mood (18%), user requests (17%), reflecting on mood (16%), technical features (16%), design (13%), and health promotion (11%). A total of 6 minor themes were also identified: notification and reminders; recommendation; privacy, security, and transparency; developer; adverts; and social/community. CONCLUSIONS: Users value mood-monitoring apps that can be personalized to their needs, have a simple and intuitive design, and allow accurate representation and review of complex and fluctuating moods. App store reviews are a valuable repository of user engagement feedback and provide a wealth of information about what users value in an app and what user needs are not being met. Users perceive mood-monitoring apps positively, but over 20% of reviews identified the need for improvement.
Subject(s)
Mobile Applications , Adolescent , Health Promotion , Humans , Mental Health , PrivacyABSTRACT
BACKGROUND: The use of new technologies and methodologies in young people's mental health research is needed to allow more frequent and reliable sampling. Mobile applications and e-platforms create exciting potential for the collection of large-scale cohort data, however there are various feasibility and ethical issues to consider. Consultation with young people is needed to inform the research agenda, and ensure these technologies are engaging, useful and safe. This article describes the process of Public and Patient Involvement (PPI) with a sample of young people in London, with the aim of i) informing the development of a mood-monitoring e-platform, and ii) providing feedback and advice for researchers developing web-based technologies in the mental health field. METHODS: A total of 26 young people were consulted across four advisory group co-design sessions. All young people were students enrolled at one of the participating London based sixth form colleges, and voluntarily attended a workshop session. Audio recordings of the sessions were analysed using a thematic analysis framework. RESULTS: We found that young people were engaged in discussions around mobile health technologies and valued the opportunity to collaborate throughout the early stages of the development process The advisory groups identified key considerations for future web-development work to encourage engagement and prolonged use, including, the promotion of trust and transparency, consideration of accessibility, provision of support, production of engaging and functional design, and acknowledgment of specific contextual influences surrounding young people's wellbeing. CONCLUSIONS: Involving young people in the development process of e-health technologies contributes to optimising the successful adoption and prolonged usage of new methodologies. The thematic map and informant examples can be used to guide researchers interested in developing web-based technologies in the mental health field and will be directly applicable to the development of a mood-monitoring e-platform.
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Bioprinting is an emerging additive manufacturing approach to the fabrication of patient-specific, implantable three-dimensional (3D) constructs for regenerative medicine. However, developing cell-compatible bioinks with high printability, structural stability, biodegradability, and bioactive characteristics is still a primary challenge for translating 3D bioprinting technology to preclinical and clinal models. To overcome this challenge, we developed a nanoengineered ionic covalent entanglement (NICE) bioink formulation for 3D bone bioprinting. The NICE bioinks allow precise control over printability, mechanical properties, and degradation characteristics, enabling custom 3D fabrication of mechanically resilient, cellularized structures. We demonstrate cell-induced remodeling of 3D bioprinted scaffolds over 60 days, demonstrating deposition of nascent extracellular matrix proteins. Interestingly, the bioprinted constructs induce endochondral differentiation of encapsulated human mesenchymal stem cells (hMSCs) in the absence of osteoinducing agent. Using next-generation transcriptome sequencing (RNA-seq) technology, we establish the role of nanosilicates, a bioactive component of NICE bioink, to stimulate endochondral differentiation at the transcriptome level. Overall, the osteoinductive bioink has the ability to induce formation of osteo-related mineralized extracellular matrix by encapsulated hMSCs in growth factor-free conditions. Furthermore, we demonstrate the ability of NICE bioink to fabricate patient-specific, implantable 3D scaffolds for repair of craniomaxillofacial bone defects. We envision development of this NICE bioink technology toward a realistic clinical process for 3D bioprinting patient-specific bone tissue for regenerative medicine.
Subject(s)
Bioprinting/trends , Bone and Bones/chemistry , Tissue Engineering , Tissue Scaffolds/chemistry , Biological Specimen Banks , Extracellular Matrix/chemistry , Extracellular Matrix/transplantation , Humans , Printing, Three-Dimensional , Regenerative Medicine/trendsABSTRACT
INTRODUCTION: The use of linked data and non-consent methodologies is a rapidly growing area of health research due to the increasing detail, availability and scope of routinely collected electronic health records data. However, gaining the necessary legal and governance approvals to undertake data linkage is a complex process in England. OBJECTIVES: We reflect on our own experience of establishing lawful basis for data linkage through Section 251 approval, with the intention to build a knowledgebase of practical advice for future applicants. METHODS: Thematic analysis was conducted on a corpus of Section 251 feedback reports from the NHS Health Research Authority Confidentiality Advisory Group. RESULTS: Four themes emerged from the feedback. These were: (a) Patient and Public Involvement, (b) Establishing Rationale, (c) Data maintenance and contingency, and the need to gain (d) Further Permissions from external authorities prior to full approval. CONCLUSIONS: Securing Section 251 approval poses ethical, practical and governance challenges. However, through a comprehensive, planned approach Section 251 approval is possible, enabling researchers to unlock the potential of linked data for the purposes of health research.
ABSTRACT
Clay nanomaterials are an emerging class of 2D biomaterials of interest due to their atomically thin layered structure, charged characteristics, and well-defined composition. Synthetic nanoclays are plate-like polyions composed of simple or complex salts of silicic acids with a heterogeneous charge distribution and patchy interactions. Due to their biocompatible characteristics, unique shape, high surface-to-volume ratio, and charge, nanoclays are investigated for various biomedical applications. Here, a critical overview of the physical, chemical, and physiological interactions of nanoclay with biological moieties, including cells, proteins, and polymers, is provided. The state-of-the-art biomedical applications of 2D nanoclay in regenerative medicine, therapeutic delivery, and additive manufacturing are reviewed. In addition, recent developments that are shaping this emerging field are discussed and promising new research directions for 2D nanoclay-based biomaterials are identified.
Subject(s)
Biocompatible Materials/chemistry , Clay/chemistry , Drug Delivery Systems/methods , Nanostructures/chemistry , Regenerative Medicine/methods , Animals , Humans , Polymers/chemistry , Printing, Three-Dimensional , Proteins/chemistry , Silicates/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistryABSTRACT
We present a nanoengineered system for sustained and prolonged delivery of protein therapeutics, which has the potential to impact current orthopedic regeneration strategies. Specifically, we introduce two-dimensional nanosilicates with a high surface area and charged characteristics for delivery of active proteins for more than 30 days. The nanosilicates show high binding efficacy without altering the protein conformation and bioactivity. The released proteins are able to maintain high activity as demonstrated by enhanced differentiation of human mesenchymal stem cells at 10-fold lower concentration compared to the exogenous control. Utilizing the nanosilicates as a delivery vehicle could minimize the negative side effects observed because of the use of supraphysiological dosages of protein therapeutics for orthopedic regeneration strategies.
Subject(s)
Bone Morphogenetic Protein 2 , Cell Differentiation/drug effects , Mesenchymal Stem Cells/metabolism , Bone Morphogenetic Protein 2/chemistry , Bone Morphogenetic Protein 2/pharmacokinetics , Bone Morphogenetic Protein 2/pharmacology , Cell Line , Delayed-Action Preparations/chemistry , Delayed-Action Preparations/pharmacokinetics , Delayed-Action Preparations/pharmacology , Humans , Mesenchymal Stem Cells/cytologyABSTRACT
Two-dimensional nanomaterials, an ultrathin class of materials such as graphene, nanoclays, transition metal dichalcogenides (TMDs), and transition metal oxides (TMOs), have emerged as a new generation of materials due to their unique properties relative to macroscale counterparts. However, little is known about the transcriptome dynamics following exposure to these nanomaterials. Here, we investigate the interactions of 2D nanosilicates, a layered clay, with human mesenchymal stem cells (hMSCs) at the whole-transcriptome level by high-throughput sequencing (RNA-seq). Analysis of cell-nanosilicate interactions by monitoring changes in transcriptome profile uncovered key biophysical and biochemical cellular pathways triggered by nanosilicates. A widespread alteration of genes was observed due to nanosilicate exposure as more than 4,000 genes were differentially expressed. The change in mRNA expression levels revealed clathrin-mediated endocytosis of nanosilicates. Nanosilicate attachment to the cell membrane and subsequent cellular internalization activated stress-responsive pathways such as mitogen-activated protein kinase (MAPK), which subsequently directed hMSC differentiation toward osteogenic and chondrogenic lineages. This study provides transcriptomic insight on the role of surface-mediated cellular signaling triggered by nanomaterials and enables development of nanomaterials-based therapeutics for regenerative medicine. This approach in understanding nanomaterial-cell interactions illustrates how change in transcriptomic profile can predict downstream effects following nanomaterial treatment.
Subject(s)
Gene Expression Profiling , Gene Expression Regulation/drug effects , MAP Kinase Signaling System/drug effects , Mesenchymal Stem Cells/metabolism , Nanoparticles , Silicates/pharmacology , Transcriptome/drug effects , Clathrin/metabolism , Endocytosis/drug effects , High-Throughput Nucleotide Sequencing , Humans , Mesenchymal Stem Cells/cytologyABSTRACT
We introduce an enhanced nanoengineered ionic-covalent entanglement (NICE) bioink for the fabrication of mechanically stiff and elastomeric 3D biostructures. NICE bioink formulations combine nanocomposite and ionic-covalent entanglement (ICE) strengthening mechanisms to print customizable cell-laden constructs for tissue engineering with high structural fidelity and mechanical stiffness. Nanocomposite and ICE strengthening mechanisms complement each other through synergistic interactions, improving mechanical strength, elasticity, toughness, and flow properties beyond the sum of the effects of either reinforcement technique alone. Herschel-Bulkley flow behavior shields encapsulated cells from excessive shear stresses during extrusion. The encapsulated cells readily proliferate and maintain high cell viability over 120 days within the 3D-printed structure, which is vital for long-term tissue regeneration. A unique aspect of the NICE bioink is its ability to print much taller structures, with higher aspect ratios, than can be achieved with conventional bioinks without requiring secondary supports. We envision that NICE bioinks can be used to bioprint complex, large-scale, cell-laden constructs for tissue engineering with high structural fidelity and mechanical stiffness for applications in custom bioprinted scaffolds and tissue engineered implants.
Subject(s)
Printing, Three-Dimensional , Bioprinting , Cell Survival , Tissue Engineering , Tissue ScaffoldsABSTRACT
Non-union defects of bone are a major problem in orthopedics, especially for patients with a low healing capacity. Fixation devices and osteoconductive materials are used to provide a stable environment for osteogenesis and an osteogenic component such as autologous human bone marrow (hBM) is then used, but robust bone formation is contingent on the healing capacity of the patients. A safe and rapid procedure for improvement of the osteoanabolic properties of hBM is, therefore, sought after in the field of orthopedics, especially if it can be performed within the temporal limitations of the surgical procedure, with minimal manipulation, and at point-of-care. One way to achieve this goal is to stimulate canonical Wingless (cWnt) signaling in bone marrow-resident human mesenchymal stem cells (hMSCs), the presumptive precursors of osteoblasts in bone marrow. Herein, we report that the effects of cWnt stimulation can be achieved by transient (1-2 hours) exposure of osteoprogenitors to the GSK3ß-inhibitor (2'Z,3'E)-6-bromoindirubin-3'-oxime (BIO) at a concentration of 800 nM. Very-rapid-exposure-to-BIO (VRE-BIO) on either hMSCs or whole hBM resulted in the long-term establishment of an osteogenic phenotype associated with accelerated alkaline phosphatase activity and enhanced transcription of the master regulator of osteogenesis, Runx2. When VRE-BIO treated hBM was tested in a rat spinal fusion model, VRE-BIO caused the formation of a denser, stiffer, fusion mass as compared with vehicle treated hBM. Collectively, these data indicate that the VRE-BIO procedure may represent a rapid, safe, and point-of-care strategy for the osteogenic enhancement of autologous hBM for use in clinical orthopedic procedures. Stem Cells Translational Medicine 2018;7:342-353.