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Overview of approved and upcoming vaccines for SARS-CoV-2: a living review.
The rapid design and implementation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines is testament to a successfully coordinated global research effort. While employing a variety of different technologies, some of which have been used for the first time, all approved vaccines demonstrate high levels of efficacy with excellent safety profiles. Despite this, there remains an urgent global demand for coronavirus disease 2019 vaccines that require further candidates to pass phase 3 clinical trials. In the expectation of SARS-CoV-2 becoming endemic, researchers are looking to adjust the vaccine constructs to tackle emerging variants. In this review, we outline different platforms used for approved vaccines and summarize latest research data with regards to immunogenicity, dosing regimens and efficiency against emerging variants.
Liposomic lubricants suppress acute inflammatory gene regulation in the joint in vivo.
Osteoarthritis (OA) is a widespread, debilitating joint disease associated with articular cartilage degradation. It is driven via mechano-inflammatory pathways, whereby catabolic genes in the cartilage-embedded chondrocytes are presumed up-regulated due to increased shear stress arising from friction at the cartilage surface as joints articulate. The enhanced expression of these cartilage-degrading and inflammatory genes leads to tissue degeneration. However, the nature of the stress, and how the cells within the joint respond to it, are poorly understood. Here we show, in a proof of concept study on a mouse model where surgical joint destabilisation has been carried out to induce OA, that the early up-regulation of the matrix metalloproteinase 3 (Mmp3) gene, a member of the matrix-degrading MMP family, and of the interleukin-1 beta (Il1b) gene, a key mediator of inflammatory response, are significantly suppressed when lipid-based lubricants are injected into the joints. We attribute this to the reduction in frictional stress on the chondrocytes due to the lubricant at the cartilage surface. At the same time, Timp1, a compression but not shear-stress sensitive gene, is unaffected by lubricant. Our results demonstrate that cartilage lubrication modulates catabolic gene regulation in OA, shed strong light on the nature of the chondrocytes' response to shear stress, and have clear implications for novel OA treatments. STATEMENT OF SIGNIFICANCE: Osteoarthritis (OA) is a widespread, debilitating joint disease associated with degradation of the articular cartilage, the tissue that covers and protects the joint surfaces as they rotate. Such degradation is due to catabolic enzymes expressed by cartilage-embedded chondrocytes (the only cell type in cartilage) in response to mechanical stress. In this proof-of-concept study in a mouse OA model, we show that reduction of cartilage friction by liposome-based lubricants suppresses the production of the catabolic, OA-related genes in chondrocytes. Our findings provide direct evidence in an animal model that catabolic genes are induced in chondrocytes in a mechanosensitive manner, related to the friction at the cartilage surface, and identify putative novel OA treatments through efficient cartilage lubrication.
Modeling and Assessing Osteoarthritis in Mice by Destabilization of the Medial Meniscus (DMM).
In this chapter, we describe an induced model of osteoarthritis in mice, frequently employed in the study of this disease. We outline in detail the surgical induction of disease and preparation of samples for histological assessment of disease.
Development of methodology to support molecular endotype discovery from synovial fluid of individuals with knee osteoarthritis: The STEpUP OA consortium.
OBJECTIVES: To develop a protocol for largescale analysis of synovial fluid proteins, for the identification of biological networks associated with subtypes of osteoarthritis. METHODS: Synovial Fluid To detect molecular Endotypes by Unbiased Proteomics in Osteoarthritis (STEpUP OA) is an international consortium utilising clinical data (capturing pain, radiographic severity and demographic features) and knee synovial fluid from 17 participating cohorts. 1746 samples from 1650 individuals comprising OA, joint injury, healthy and inflammatory arthritis controls, divided into discovery (n = 1045) and replication (n = 701) datasets, were analysed by SomaScan Discovery Plex V4.1 (>7000 SOMAmers/proteins). An optimised approach to standardisation was developed. Technical confounders and batch-effects were identified and adjusted for. Poorly performing SOMAmers and samples were excluded. Variance in the data was determined by principal component (PC) analysis. RESULTS: A synovial fluid standardised protocol was optimised that had good reliability (<20% co-efficient of variation for >80% of SOMAmers in pooled samples) and overall good correlation with immunoassay. 1720 samples and >6290 SOMAmers met inclusion criteria. 48% of data variance (PC1) was strongly correlated with individual SOMAmer signal intensities, particularly with low abundance proteins (median correlation coefficient 0.70), and was enriched for nuclear and non-secreted proteins. We concluded that this component was predominantly intracellular proteins, and could be adjusted for using an 'intracellular protein score' (IPS). PC2 (7% variance) was attributable to processing batch and was batch-corrected by ComBat. Lesser effects were attributed to other technical confounders. Data visualisation revealed clustering of injury and OA cases in overlapping but distinguishable areas of high-dimensional proteomic space. CONCLUSIONS: We have developed a robust method for analysing synovial fluid protein, creating a molecular and clinical dataset of unprecedented scale to explore potential patient subtypes and the molecular pathogenesis of OA. Such methodology underpins the development of new approaches to tackle this disease which remains a huge societal challenge.
Manufacture of Soft-Hard Implants from Electrospun Filaments Embedded in 3D Printed Structures.
Rotator cuff tendon tears are common injuries of the musculoskeletal system that often require surgical repair. However, re-tearing following repair is a significant clinical problem, with a failure rate of up to 40%, notably at the transition from bone to tendon. The development of biphasic materials consisting of soft and hard components, which can mimic this interface, is therefore promising. Here, a simple manufacturing approach is proposed that combines electrospun filaments and 3D printing to achieve scaffolds made of a soft polydioxanone cuff embedded in a porous polycaprolactone block. The insertion area of the cuff is based on the supraspinatus tendon footprint and the size of the cuff is scaled up from 9 to 270 electrospun filaments to reach a clinically relevant strength of 227N on average. The biological evaluation shows that the biphasic scaffold components are noncytotoxic, and that tendon and bone cells can be grown on the cuff and block, respectively. Overall, these results indicate that combining electrospinning and 3D printing is a feasible and promising approach to create soft-to-hard biphasic scaffolds that can improve the outcomes of rotator cuff repair.
Electrospun Scaffold Micro-Architecture Induces an Activated Transcriptional Phenotype within Tendon Fibroblasts.
Biomaterial augmentation of surgically repaired rotator cuff tendon tears aims to improve the high failure rates (∼40%) of traditional repairs. Biomaterials that can alter cellular phenotypes through the provision of microscale topographical cues are now under development. We aimed to systematically evaluate the effect of topographic architecture on the cellular phenotype of fibroblasts from healthy and diseased tendons. Electrospun polydioxanone scaffolds with fiber diameters ranging from 300 to 4000 nm, in either a highly aligned or random configuration, were produced. Healthy tendon fibroblasts cultured for 7 days on scaffolds with highly aligned fibers demonstrated a distinctive elongated morphology, whilst those cultured on randomly configured fibers demonstrated a flattened and spread morphology. The effect of scaffold micro-architecture on the transcriptome of both healthy and diseased tendon fibroblasts was assessed with bulk RNA-seq. Both healthy (n = 3) and diseased tendon cells (n = 3) demonstrated a similar transcriptional response to architectural variants. Gene set enrichment analysis revealed that large diameter (≥2000 nm) aligned scaffolds induced an upregulation of genes involved in cellular replication and a downregulation of genes defining inflammatory responses and cell adhesion. Similarly, PDPN and CD248, markers of inflammatory or "activated" fibroblasts, were downregulated during culture of both healthy and diseased fibroblasts on aligned scaffolds with large (≥2000 nm) fiber diameters. In conclusion scaffold architectures resembling that of disordered type III collagen, typically present during the earlier phases of wound healing, resulted in tendon fibroblast activation. Conversely, scaffolds mimicking aligned diameter collagen I fibrils, present during tissue remodelling, did not activate tendon derived fibroblasts. This has implications for the design of scaffolds used during rotator cuff repair augmentation.
A longitudinal cohort study of adolescent elite footballers and controls investigating the development of cam morphology.
Cam morphology describes an asphericity of the femoral head that develops during adolescence, is highly prevalent in athletes, and predisposes individuals to future osteoarthritis. However, it's aetiology remains poorly understood. The aim of this study was to perform 3-year longitudinal follow-up of a control population and football club academy cohort to compare the change in hip and growth plate anatomy between athletes and controls. MRI and questionnaires were used to characterise change in hip and growth plate anatomy and quantify activity levels. 121 male academy footballers and 107 male and female controls participated at baseline. Footballers experienced significantly greater increases in femoral head asphericity (4.83 degrees (95% CI: 2.84 to 6.82), p
Predictive genetic testing for Huntington's disease: Exploring participant experiences of uncertainty and ambivalence between clinic appointments.
Ambivalence and uncertainty are key themes throughout the psychology of healthcare literature. This is especially so for individuals at risk of Huntington's disease (HD) deliberating the decision to undergo genetic testing because there is currently no treatment that modifies disease progression. A better understanding of the experience of making a decision about genetic prediction will help practitioners support and guide individuals through this process. Our aim was to capture participants' experiences of uncertainty and ambivalence in between their genetic counseling appointments. We explored these issues through the experiences of nine participants who were referred for predictive HD testing at four regional genetics services in England and Wales. Data consisted of recordings of clinic consultations, diaries, and an in-depth interview conducted at the end of the testing process. Data were analyzed thematically. Four themes were identified representing four possible futures, each future dependent on the decision to undergo testing and the result of that test. Our results showed that participants, as well as attending more to a future that represents their current situation of not having undergone predictive testing, also attended more to a distant future where a positive predictive result is received and symptoms have started. Participants attended less to the two futures that were more immediate once testing was undertaken (a future where a positive result is received and symptoms have not started and a future where a negative result is received). The use of diaries gave us a unique insight into these participants' experiences of ambivalence and uncertainty, psychological distress, and the emotional burden experienced. These findings help inform discussions within the clinic appointment as well as encourage researchers to consider diary use as a method of exploring what happens for individuals outside of clinical encounters.
U–Pb zircon–rutile dating of the Llangynog Inlier, Wales: constraints on an Ediacaran shallow-marine fossil assemblage from East Avalonia
The Llangynog Inlier of south Wales contains an assemblage of Ediacaran macrofossils from a shallow-marine environment, including discoidal morphs of Aspidella and rare examples of Hiemalora, Palaeopascichnus and Yelovichnus. These are taxa found at other sites in the Avalonian microcontinent (e.g. Charnwood Forest and eastern Newfoundland) and in the younger White Sea Ediacaran assemblages. As the Charnwood fossils reflect a deep-water environment, and no macrofossils have been found in the Ediacaran rocks of the Long Mynd, the fossils of the Llangynog Inlier represent a unique glimpse of shallow-marine life in southern Britain (East Avalonia). However, the lack of absolute age constraints has hampered direct comparison with other assemblages. Here, we report in situ zircon and rutile U–Pb dates from a rhyolitic ash-flow layer of the Coed Cochion Volcaniclastic Member, Llangynog Inlier, which constrains the age of the fossiliferous strata. A weighted mean single grain zircon isotope dilution thermal ionization mass spectrometry U–Pb age of 564.09 ± 0.70 Ma is interpreted as the rhyolite’s crystallization age. This age is consistent with in situ laser ablation inductively coupled plasma mass spectrometry zircon and rutile U–Pb dating. The Llangynog age temporally correlates these fossils to dated horizons within East Avalonia at the Beacon Hill Formation, Charnwood (565.22 ± 0.89 Ma) and the Stretton Shale Formation, Long Mynd (566.6 ± 2.9 Ma). Correlations to West Avalonia include the time-equivalent Fermeuse Formation, St John’s Group, eastern Newfoundland (564.13 ± 0.65 Ma). The data presented here establish the biota of the Llangynog Inlier as a lateral equivalent to the similarly shallow-marine, tidally influenced ecosystem of the upper Fermeuse Formation. Intra-terrane depositional environmental variability also affects what is preserved in Avalonian fossil sites. Further, time-constrained geochemical data reinforce the Llangynog Inlier’s classification within the Wrekin Terrane.
Somatic mutations in salivary duct carcinoma and potential therapeutic targets.
BACKGROUND: Salivary duct carcinomas (SDCa) are rare highly aggressive malignancies. Most patients die from distant metastatic disease within three years of diagnosis. There are limited therapeutic options for disseminated disease. RESULTS: 11 cases showed androgen receptor expression and 6 cases showed HER2 amplification. 6 Somatic mutations with additional available targeted therapies were identified: EGFR (p.G721A: Gefitinib), PDGFRA (p.H845Y: Imatinib and Crenolanib), PIK3CA (p.H1047R: Everolimus), ERBB2 (p.V842I: Lapatinib), HRAS (p.Q61R: Selumetinib) and KIT (p.T670I: Sorafenib). Furthermore, alterations in PTEN, PIK3CA and HRAS that alter response to androgen deprivation therapy and HER2 inhibition were also seen. MATERIALS AND METHODS: Somatic mutation analysis was performed on DNA extracted from 15 archival cases of SDCa using the targeted Illumina TruSeq Amplicon Cancer Panel. Potential targetable genetic alterations were identified using extensive literature and international somatic mutation database (COSMIC, KEGG) search. Immunohistochemistry for androgen receptor and immunohistochemistry and fluorescent in situ hybridization for HER2 were also performed. CONCLUSIONS: SDCa show multiple somatic mutations, some that are amenable to pharmacologic manipulation and others that confer resistance to treatments currently under investigation. These findings emphasize the need to develop testing and treatment strategies for SDCa.
Diagnosis and Management of Multifocal Motor Neuropathy in the United Kingdom: A Multicentre Survey.
BACKGROUND: We conducted a survey to determine the current diagnosis and treatment of multifocal motor neuropathy (MMN) in the United Kingdom. METHODS: Demographic, diagnostic and treatment data were collected at nine UK neuroscience centres. RESULTS: Ninety-five subjects were included. Mean age at diagnosis was 49.9 years (SD: 11.4). Males were more commonly affected (ratio: 1.9:1). Diagnostic delay was > 1 year from the time of first neurological assessment, in > 50% of subjects. Applying modified EFNS/PNS 2010 criteria, 69/95 (72.6%) had definite MMN, 10/95 (10.5%) had probable MMN, 15/95 (15.8%) had possible MMN, through treatment responsiveness in 9/15 (60%) and 1/95 (1.1%) did not meet criteria. Cerebrospinal fluid examination, anti-GM1 antibody testing and brachial plexus magnetic resonance imaging were non-contributory. Immunoglobulin response was reported in 90/92 subjects (97.8%), and 84/90 (93.3%) remained on treatment after a mean of 9.4 years, at a mean dose of 26.2 g/week (range: 4-114). Mean long-term immunoglobulin dose was 30%-60% higher than reported in neighbouring countries. Contrasting with previous reports of frequent loss of immunoglobulin response and functional decline, our physician-assessed long-term outcome was favourable (stable or improving) in 74/84 (88.1%) treated subjects. INTERPRETATION: MMN diagnosis and treatment in the United Kingdom are comparable to that of neighbouring countries and follow existing guidelines. Diagnostic delay after the first neurological assessment is considerable. Electrophysiology shows at least one definite/probable conduction block in nearly 90% of cases. The mean long-term immunoglobulin dose is higher in the United Kingdom than reported elsewhere, although highly variable. Whether higher doses of immunoglobulin may improve long-term outcomes requires further study.
Pathologic RFC1 repeat expansions do not contribute to the development of inflammatory neuropathies.
Biallelic expansions of the AAGGG repeat in the replication factor C subunit 1 (RFC1) have recently been described to be responsible for cerebellar ataxia, peripheral neuropathy and vestibular areflexia syndrome. This genetic alteration has also allowed genetic classification in up to one-third of cases with idiopathic sensory neuropathy. Here, we screened a well-characterized cohort of inflammatory neuropathy patients for RFC1 repeat expansions to explore whether RFC1 was increased from background rates and possibly involved in the pathogenesis of inflammatory neuropathy. A total of 259 individuals with inflammatory neuropathy and 243 healthy controls were screened for the AAGGG repeat expansion using short-range flanking PCR and repeat-primed PCR. Cases without amplifiable PCR product on flanking PCR and positive repeat-primed PCR were also tested for the mostly non-pathogenic expansions of the AAAGG and AAAAG repeat units. None of the patients showed biallelic AAGGG expansion of RFC1, and their carrier frequency for AAGGG was comparable with controls [n = 27 (5.2%) and n = 23 (4.7%), respectively; P > 0.5]. Data suggest that the pathologic expansions of AAGGG repeats do not contribute to the development of inflammatory neuropathies nor lead to misdiagnosed cases. Accordingly, routine genetic screening for RFC1 repeat expansion is not indicated in this patient population.
Stiff person syndrome.
Stiff Person syndrome (SPS) is a rare autoimmune disorder of the central nervous system characterized by stiffness and spasms in the lumbar and proximal lower limb muscles. Nonmotor symptoms include phobias, anxiety, and depression. SPS exists on a spectrum ranging from a focal disease known as the stiff limb syndrome to progressive encephalomyelitis with rigidity and myoclonus. Collectively, these conditions may be referred to as stiff person spectrum disorders, as they share similar core clinical features and autoantibodies against several neuronal proteins, which are involved in modulating central hyperexcitability. Antibodies against the glutamic acid decarboxylase enzyme are most frequently associated with SPS but their role in disease pathogenesis remains uncertain. Other antibodies associated with SPS now include those against the glycine receptor, amphiphysin, dipeptidyl-peptidase-like protein 6, gephyrin, γ-aminobutyric acid receptor A (GABAAR), and the GABAAR-associated protein. First-line treatments for SPS include diazepam and baclofen. Patients who do not respond adequately may benefit from immunotherapy. Intravenous immunoglobulin has the most supporting evidence, and while several other immunotherapies are used, further trials are required to determine their efficacy. Further studies to establish the precise role of autoantibodies in the pathogenesis of SPS are also needed to better understand and manage this disabling condition.
Editorial Commentary: Evidence for Patch Augmentation of Rotator Cuff Repair Is Weak.
Rotator cuff repair has a substantial failure rate despite various attempts to improve outcome and prevent a retear. Patch augmentation is an intuitively appealing approach to seek to reduce failure rate and improve outcomes for patients. Two main augmentation approaches are used: "on-lay" and "bridging." The literature is heterogeneous, and the best approach is uncertain. The evidence on patch augmentation for rotator cuff repair is both disparate and weak. Large randomized trials and registry data are required to move the field, ensure patient safety, and avoid wasting precious resources.
Diagnosis and investigation of suspected haemophagocytic lymphohistiocytosis in adults: 2023 Hyperinflammation and HLH Across Speciality Collaboration (HiHASC) consensus guideline.
Haemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome characterised by persistently activated cytotoxic lymphocytes and macrophages, which, if untreated, leads to multiorgan dysfunction and death. HLH should be considered in any acutely unwell patient not responding to treatment as expected, with prompt assessment to look for what we term the three Fs-fever, falling blood counts, and raised ferritin. Worldwide, awareness of HLH and access to expert management remain inequitable. Terminology is not standardised, classification criteria are validated in specific patient groups only, and some guidelines rely on specialised and somewhat inaccessible tests. The consensus guideline described in this Health Policy was produced by a self-nominated working group from the UK network Hyperinflammation and HLH Across Speciality Collaboration (HiHASC), a multidisciplinary group of clinicians experienced in managing people with HLH. Combining literature review and experience gained from looking after patients with HLH, it provides a practical, structured approach for all health-care teams managing adult (>16 years) patients with possible HLH. The focus is on early recognition and diagnosis of HLH and parallel identification of the underlying cause. To ensure wide applicability, the use of inexpensive, readily available tests is prioritised, but the role of specialist investigations and their interpretation is also addressed.
Contactin-1 links autoimmune neuropathy and membranous glomerulonephritis.
Membranous glomerulonephritis (MGN) is a common cause of nephrotic syndrome in adults, mediated by glomerular antibody deposition to an increasing number of newly recognised antigens. Previous case reports have suggested an association between patients with anti-contactin-1 (CNTN1)-mediated neuropathies and MGN. In an observational study we investigated the pathobiology and extent of this potential cause of MGN by examining the association of antibodies against CNTN1 with the clinical features of a cohort of 468 patients with suspected immune-mediated neuropathies, 295 with idiopathic MGN, and 256 controls. Neuronal and glomerular binding of patient IgG, serum CNTN1 antibody and protein levels, as well as immune-complex deposition were determined. We identified 15 patients with immune-mediated neuropathy and concurrent nephrotic syndrome (biopsy proven MGN in 12/12), and 4 patients with isolated MGN from an idiopathic MGN cohort, all seropositive for IgG4 CNTN1 antibodies. CNTN1-containing immune complexes were found in the renal glomeruli of patients with CNTN1 antibodies, but not in control kidneys. CNTN1 peptides were identified in glomeruli by mass spectroscopy. CNTN1 seropositive patients were largely resistant to first-line neuropathy treatments but achieved a good outcome with escalation therapies. Neurological and renal function improved in parallel with suppressed antibody titres. The reason for isolated MGN without clinical neuropathy is unclear. We show that CNTN1, found in peripheral nerves and kidney glomeruli, is a common target for autoantibody-mediated pathology and may account for between 1 and 2% of idiopathic MGN cases. Greater awareness of this cross-system syndrome should facilitate earlier diagnosis and more timely use of effective treatment.
Asymmetric cell division safeguards memory CD8 T cell development.
The strength of T cell receptor (TCR) stimulation and asymmetric distribution of fate determinants are both implied to affect T cell differentiation. Here, we uncover asymmetric cell division (ACD) as a safeguard mechanism for memory CD8 T cell generation specifically upon strong TCR stimulation. Using live imaging approaches, we find that strong TCR stimulation induces elevated ACD rates, and subsequent single-cell-derived colonies comprise both effector and memory precursor cells. The abundance of memory precursor cells emerging from a single activated T cell positively correlates with first mitosis ACD. Accordingly, preventing ACD by inhibition of protein kinase Cζ (PKCζ) during the first mitosis upon strong TCR stimulation markedly curtails the formation of memory precursor cells. Conversely, no effect of ACD on fate commitment is observed upon weak TCR stimulation. Our data provide relevant mechanistic insights into the role of ACD for CD8 T cell fate regulation upon different activation conditions.
Neutralization of excessive levels of active TGF-β1 reduces MSC recruitment and differentiation to mitigate peritendinous adhesion.
Peritendinous adhesion formation (PAF) can substantially limit the range of motion of digits. However, the origin of myofibroblasts in PAF tissues is still unclear. In this study, we found that the concentration of active TGF-β1 and the numbers of macrophages, mesenchymal stromal cells (MSCs), and myofibroblasts in human and mouse adhesion tissues were increased. Furthermore, knockout of TGF-β1 in macrophages or TGF-β1R2 in MSCs inhibited PAF by reducing MSC and myofibroblast infiltration and collagen I and III deposition, respectively. Moreover, we found that MSCs differentiated into myofibroblasts to form adhesion tissues. Systemic injection of the TGF-β-neutralizing antibody 1D11 during the granulation formation stage of PAF significantly reduced the infiltration of MSCs and myofibroblasts and, subsequently, PAF. These results suggest that macrophage-derived TGF-β1 recruits MSCs to form myofibroblasts in peritendinous adhesions. An improved understanding of PAF mechanisms could help identify a potential therapeutic strategy.