RESUMEN
Loss-of-function (LoF) variants in the filaggrin (FLG) gene are the strongest known genetic risk factor for atopic dermatitis (AD), but the impact of these variants on AD outcomes is poorly understood. We comprehensively identified genetic variants through targeted region sequencing of FLG in children participating in the Mechanisms of Progression of Atopic Dermatitis to Asthma in Children cohort. Twenty FLG LoF variants were identified, including 1 novel variant and 9 variants not previously associated with AD. FLG LoF variants were found in the cohort. Among these children, the presence of 1 or more FLG LoF variants was associated with moderate/severe AD compared with those with mild AD. Children with FLG LoF variants had a higher SCORing for Atopic Dermatitis (SCORAD) and higher likelihood of food allergy within the first 2.5 years of life. LoF variants were associated with higher transepidermal water loss (TEWL) in both lesional and nonlesional skin. Collectively, our study identifies established and potentially novel AD-associated FLG LoF variants and associates FLG LoF variants with higher TEWL in lesional and nonlesional skin.
Asunto(s)
Dermatitis Atópica , Proteínas Filagrina , Proteínas de Filamentos Intermediarios , Mutación con Pérdida de Función , Fenotipo , Dermatitis Atópica/genética , Dermatitis Atópica/patología , Humanos , Masculino , Femenino , Preescolar , Estudios Prospectivos , Lactante , Proteínas de Filamentos Intermediarios/genética , Predisposición Genética a la Enfermedad , Niño , Hipersensibilidad a los Alimentos/genéticaRESUMEN
BACKGROUND: Presently, there is limited guidance on the maximal dosing of psychosis drugs that is based on effectiveness rather than safety or toxicity. Current maximum dosing recommendations may far exceed the necessary degree of dopamine D2 receptor blockade required to treat psychosis. This may lead to excess harm through cognitive impairment and side effects. AIMS: This analysis aimed to establish guidance for prescribers by optimally dosing drugs for psychosis based on efficacy and benefit. METHODS: We used data from two dose-response meta-analyses and reviewed seven of the most prescribed drugs for psychosis in the UK. Where data were not available, we used appropriate comparison techniques based on D2 receptor occupancy to extrapolate our recommendations. RESULTS: We found that the likely threshold dose for achieving remission of psychotic symptoms was often significantly below the currently licensed dose for these drugs. We therefore recommend that clinicians are cautious about exceeding our recommended doses. Individual factors, however, should be accounted for. We outline potentially relevant factors including age, ethnicity, sex, smoking status and pharmacogenetics. Additionally, we recommend therapeutic drug monitoring as a tool to determine individual pharmacokinetic variation. CONCLUSIONS: In summary, we propose a new set of maximum target doses for psychosis drugs based on efficacy. Further research through randomised controlled trials should be undertaken to evaluate the effect of reducing doses from current licensing maximums or from doses that are above our recommendations. However, dose reductions should be implemented in a manner that accounts for and reduces the effects of drug withdrawal.
Asunto(s)
Antipsicóticos , Trastornos Psicóticos , Humanos , Antipsicóticos/efectos adversos , Trastornos Psicóticos/tratamiento farmacológicoRESUMEN
Background: Collared femoral stems have been considered to reduce the risk of early subsidence over collarless stems. However, with advances in material technology, new surface treatments have been introduced into cementless stem design to enhance primary fixation and long-term stability. This study aims to analyze the early migration behaviors of a proximally coated collarless femoral stem and cementless acetabular component and compare the outcomes with commercially available cementless stems and acetabular cups. Methods: A total of 24 patients (25 hips) undergoing total hip arthroplasty were recruited and followed up for 2 years. All patients received a Masterloc femoral stem (Medacta International SA, Castel San Pietro, Switzerland) and an Mpact acetabular component (Medacta International SA, Castel San Pietro, Switzerland) with tantalum beads embedded during the operation. Radiographs for radiostereometric analysis were taken immediately postsurgery, 6-months, 1-year, and 2-years postoperatively. Results: The median condition number for this study was 59. The median stem subsidence was -0.08 mm (-2.47 to 0.40) at 2 years. The median cup subsidence was -0.03 mm (-0.38 to 0.57) at 2 years. The migration of the Masterloc stem was less than that of other cementless collarless, as well as collared stems, as reported in literature. Conclusions: This study has demonstrated the high stability and fixation provided with the use of a collarless cementless stem. The subsidence seen in both this cementless femoral stem and acetabular cup at 2 years postoperative was below the range reported in literature for cementless collarless and collared stems.
RESUMEN
Importance: Ischemic heart disease remains the leading cause of mortality following hip and knee arthroplasty. Due to its antiplatelet and cardioprotective properties, aspirin has been proposed as an agent that could reduce mortality when used as venous thromboembolism (VTE) prophylaxis following these procedures. Objective: To compare aspirin with enoxaparin in reducing 90-day mortality for patients undergoing hip or knee arthroplasty procedures. Design, Setting, and Participants: This study was a planned secondary analysis of the CRISTAL cluster randomized, crossover, registry-nested trial performed across 31 participating hospitals in Australia between April 20, 2019, and December 18, 2020. The aim of the CRISTAL trial was to determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE following hip or knee arthroplasty. The primary study restricted the analysis to patients undergoing total hip or knee arthroplasty for a diagnosis of osteoarthritis only. This study includes all adult patients (aged ≥18 years) undergoing any hip or knee arthroplasty procedure at participating sites during the course of the trial. Data were analyzed from June 1 to September 6, 2021. Interventions: Hospitals were randomized to administer all patients oral aspirin (100 mg daily) or subcutaneous enoxaparin (40 mg daily) for 35 days after hip arthroplasty and 14 days after knee arthroplasty procedures. Main Outcomes and Measures: The primary outcome was mortality within 90 days. The between-group difference in mortality was estimated using cluster summary methods. Results: A total of 23â¯458 patients from 31 hospitals were included, with 14â¯156 patients allocated to aspirin (median [IQR] age, 69 [62-77] years; 7984 [56.4%] female) and 9302 patients allocated to enoxaparin (median [IQR] age, 70 [62-77] years; 5277 [56.7%] female). The mortality rate within 90 days of surgery was 1.67% in the aspirin group and 1.53% in the enoxaparin group (estimated difference, 0.04%; 95% CI, -0.05%-0.42%). For the subgroup of 21â¯148 patients with a nonfracture diagnosis, the mortality rate was 0.49% in the aspirin group and 0.41% in the enoxaparin group (estimated difference, 0.05%; 95% CI, -0.67% to 0.76%). Conclusions and Relevance: In this secondary analysis of a cluster randomized trial comparing aspirin with enoxaparin following hip or knee arthroplasty, there was no significant between-group difference in mortality within 90 days when either drug was used for VTE prophylaxis. Trial Registration: http://anzctr.org.au Identifier: ACTRN12618001879257.
Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Tromboembolia Venosa , Adulto , Humanos , Femenino , Adolescente , Anciano , Masculino , Enoxaparina/uso terapéutico , Enoxaparina/efectos adversos , Aspirina/uso terapéutico , Tromboembolia Venosa/tratamiento farmacológico , Artroplastia de Reemplazo de Rodilla/efectos adversos , Artroplastia de Reemplazo de Cadera/efectos adversosRESUMEN
We describe a patient with HIV who presented with hemophagocytic lymphohistiocytosis and nonspecific abdominal imaging findings. He was diagnosed with visceral leishmaniasis via bone marrow biopsy and treated in the hospital with amphotericin B infusions. Despite pharmacologic interventions, including amphotericin and miltefosine in addition to antiretroviral therapy, our patient experienced multiple relapses and a challenging clinical course.
RESUMEN
BACKGROUND: Nonsyndromic cleft lip with/without cleft palate (nsCL/P) is a congenital malformation of multifactorial etiology. Research has identified >40 genome-wide significant risk loci, which explain less than 40% of nsCL/P heritability. Studies show that some of the hidden heritability is explained by rare penetrant variants. METHODS: To identify new candidate genes, we searched for highly penetrant de novo variants (DNVs) in 50 nsCL/P patient/parent-trios with a low polygenic risk for the phenotype (discovery). We prioritized DNV-carrying candidate genes from the discovery for resequencing in independent cohorts of 1010 nsCL/P patients of diverse ethnicities and 1574 population-matched controls (replication). Segregation analyses and rare variant association in the replication cohort, in combination with additional data (genome-wide association data, expression, protein-protein-interactions), were used for final prioritization. CONCLUSION: In the discovery step, 60 DNVs were identified in 60 genes, including a variant in the established nsCL/P risk gene CDH1. Re-sequencing of 32 prioritized genes led to the identification of 373 rare, likely pathogenic variants. Finally, MDN1 and PAXIP1 were prioritized as top candidates. Our findings demonstrate that DNV detection, including polygenic risk score analysis, is a powerful tool for identifying nsCL/P candidate genes, which can also be applied to other multifactorial congenital malformations.
Asunto(s)
Labio Leporino , Fisura del Paladar , Humanos , Fisura del Paladar/genética , Labio Leporino/genética , Estudio de Asociación del Genoma Completo , Proteínas de Unión al ADN/genética , Factores de RiesgoRESUMEN
Diabetic retinopathy is the most feared complication for those with diabetes. Although visible vascular pathology traditionally defines the management of this condition, it is now recognised that a range of cellular changes occur in the retina from an early stage of diabetes. One of the most significant functional changes that occurs in those with diabetes is a loss of vasoregulation in response to changes in neural activity. There are several retinal cell types that are critical for mediating so-called neurovascular coupling, including Müller cells, microglia and pericytes. Although there is a great deal of evidence that suggests that Müller cells are integral to regulating the vasculature, they only modulate part of the vascular tree, highlighting the complexity of vasoregulation within the retina. Recent studies suggest that retinal immune cells, microglia, play an important role in mediating vasoconstriction. Importantly, retinal microglia contact both the vasculature and neural synapses and induce vasoconstriction in response to neurally expressed chemokines such as fractalkine. This microglial-dependent regulation occurs via the vasomediator angiotensinogen. Diabetes alters the way microglia regulate the retinal vasculature, by increasing angiotensinogen expression, causing capillary vasoconstriction and contributing to a loss of vascular reactivity to physiological signals. This article summarises recent studies showing changes in vascular regulation during diabetes, the potential mechanisms by which this occurs and the significance of these early changes to the progression of diabetic retinopathy.
Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Acoplamiento Neurovascular , Humanos , Angiotensinógeno/metabolismo , Retina/patología , Vasos Retinianos/patología , Microglía/metabolismo , Microglía/patologíaRESUMEN
PURPOSE: Vitamin D metabolites may be protective against prostate cancer (PCa). We conducted a cross-sectional analysis to evaluate associations between in vivo vitamin D status, genetic ancestry, and degree of apoptosis using prostatic epithelial terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining. EXPERIMENTAL DESIGN: Benign and tumor epithelial punch biopsies of participants with clinically localized PCa underwent indirect TUNEL staining. Serum levels of 25 hydroxyvitamin D [25(OH)D] and 1,25 dihydroxyvitamin D were assessed immediately before radical prostatectomy; levels of prostatic 25(OH)D were obtained from the specimen once the prostate was extracted. Ancestry informative markers were used to estimate the percentage of genetic West African, Native American, and European ancestry. RESULTS: One hundred twenty-one newly diagnosed men, age 40-79, were enrolled between 2013 and 2018. Serum 25(OH)D correlated positively with both tumor (ρ = 0.17, p = 0.03), and benign (ρ = 0.16, p = 0.04) prostatic epithelial TUNEL staining. Similarly, prostatic 25(OH)D correlated positively with both tumor (ρ = 0.31, p < 0.001) and benign (ρ = 0.20, p = 0.03) epithelial TUNEL staining. Only Native American ancestry was positively correlated with tumor (ρ = 0.22, p = 0.05) and benign (ρ = 0.27, p = 0.02) TUNEL staining. In multivariate regression models, increasing quartiles of prostatic 25(OH)D (ß = 0.25, p = 0.04) and Native American ancestry (ß = 0.327, p = 0.004) were independently associated with tumor TUNEL staining. CONCLUSIONS: Physiologic serum and prostatic 25(OH)D levels and Native American ancestry are positively associated with the degree of apoptosis in tumor and benign prostatic epithelium in clinically localized PCa. Vitamin D may have secondary chemoprevention benefits in preventing PCa progression in localized disease.
Asunto(s)
Próstata , Neoplasias de la Próstata , Masculino , Humanos , Adulto , Persona de Mediana Edad , Anciano , Próstata/patología , Estudios Transversales , Vitamina D , Neoplasias de la Próstata/patología , Epitelio/metabolismo , ApoptosisRESUMEN
The pericentromeric heterochromatin is largely composed of repetitive sequences, making it difficult to analyze with standard molecular biological methods. At the same time, it carries many functional elements with poorly understood mechanisms of action. The search for new experimental models for the analysis of heterochromatin is an urgent task. In this work, we used the Rif1 mutation, which suppresses the underreplication of all types of repeated sequences, to analyze heterochromatin regions in polytene chromosomes of Drosophila melanogaster. In the Rif1 background, we discovered and described in detail a new inversion, In(1)19EHet, which arose on a chromosome already carrying the In(1)sc8 inversion and transferred a large part of X chromosome heterochromatin, including the nucleolar organizer to a new euchromatic environment. Using nanopore sequencing and FISH, we have identified the eu- and heterochromatin breakpoints of In(1)19EHet. The combination of the new inversion and the Rif1 mutation provides a promising tool for studies of X chromosome heterochromatin structure, nucleolar organization, and the nucleolar dominance phenomenon. In particular, we found that, with the complete polytenization of rDNA repeats, the nucleolus consists of a cloud-like structure corresponding to the classical nucleolus of polytene chromosomes, as well as an unusual intrachromosomal structure containing alternating transcriptionally active and inactive regions.
Asunto(s)
Proteínas de Drosophila , Drosophila melanogaster , Animales , Drosophila melanogaster/genética , Heterocromatina/genética , Cromosoma X/genética , Secuencias Repetitivas de Ácidos Nucleicos/genética , Región Organizadora del Nucléolo , Proteínas Portadoras/genética , Proteínas de Drosophila/genéticaRESUMEN
Early diagnosis of ovarian cancer remains an urgent issue owing to the continuing trend towards increasing incidence along with only marginal improvements in mortality and 5-year survival rates. Furthermore, there is a lack of a clear formulation of the concept of pathogenesis. The diagnostic values of tumor markers, their potential advantages and disadvantages, and their combination with radiation imaging methods and transvaginal sonography are discussed. More advanced imaging techniques, such as computed tomography and magnetic resonance imaging have proven too expensive for widespread use. According to the World Health Organization, more than half of the world's population does not have access to diagnostic imaging. Consequently, there is high demand for a low-cost, reliable, and safe imaging system for detecting and monitoring cancer. Currently, there is no clear algorithm available for examining and accurately diagnosing patients with postmenopausal ovarian tumors; moreover, reliable criteria allowing dynamic observation and for determining surgical access and optimal surgical intervention measures in postmenopausal patients are lacking. Medical microwave radiometry shows promising results yielding an accuracy of 90%.
RESUMEN
Importance: There remains a lack of randomized trials investigating aspirin monotherapy for symptomatic venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA) or total knee arthroplasty (TKA). Objective: To determine whether aspirin was noninferior to enoxaparin in preventing symptomatic VTE after THA or TKA. Design, Setting, and Participants: Cluster-randomized, crossover, registry-nested trial across 31 hospitals in Australia. Clusters were hospitals performing greater than 250 THA or TKA procedures annually. Patients (aged ≥18 years) undergoing hip or knee arthroplasty procedures were enrolled at each hospital. Patients receiving preoperative anticoagulation or who had a medical contraindication to either study drug were excluded. A total of 9711 eligible patients were enrolled (5675 in the aspirin group and 4036 in the enoxaparin group) between April 20, 2019, and December 18, 2020. Final follow-up occurred on August 14, 2021. Interventions: Hospitals were randomized to administer aspirin (100 mg/d) or enoxaparin (40 mg/d) for 35 days after THA and for 14 days after TKA. Crossover occurred after the patient enrollment target had been met for the first group. All 31 hospitals were initially randomized and 16 crossed over prior to trial cessation. Main Outcomes and Measures: The primary outcome was symptomatic VTE within 90 days, including pulmonary embolism and deep venous thrombosis (DVT) (above or below the knee). The noninferiority margin was 1%. Six secondary outcomes are reported, including death and major bleeding within 90 days. Analyses were performed by randomization group. Results: Enrollment was stopped after an interim analysis determined the stopping rule was met, with 9711 patients (median age, 68 years; 56.8% female) of the prespecified 15â¯562 enrolled (62%). Of these, 9203 (95%) completed the trial. Within 90 days of surgery, symptomatic VTE occurred in 256 patients, including pulmonary embolism (79 cases), above-knee DVT (18 cases), and below-knee DVT (174 cases). The symptomatic VTE rate in the aspirin group was 3.45% and in the enoxaparin group was 1.82% (estimated difference, 1.97%; 95% CI, 0.54%-3.41%). This failed to meet the criterion for noninferiority for aspirin and was significantly superior for enoxaparin (P = .007). Of 6 secondary outcomes, none were significantly better in the enoxaparin group compared with the aspirin group. Conclusions and Relevance: Among patients undergoing hip or knee arthroplasty for osteoarthritis, aspirin compared with enoxaparin resulted in a significantly higher rate of symptomatic VTE within 90 days, defined as below- or above-knee DVT or pulmonary embolism. These findings may be informed by a cost-effectiveness analysis. Trial Registration: ANZCTR Identifier: ACTRN12618001879257.
Asunto(s)
Anticoagulantes , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Aspirina , Enoxaparina , Tromboembolia Venosa , Anciano , Anticoagulantes/efectos adversos , Anticoagulantes/uso terapéutico , Artroplastia de Reemplazo de Cadera/efectos adversos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Aspirina/efectos adversos , Aspirina/uso terapéutico , Australia , Quimioprevención , Enoxaparina/efectos adversos , Enoxaparina/uso terapéutico , Femenino , Humanos , Masculino , Osteoartritis/cirugía , Complicaciones Posoperatorias/prevención & control , Embolia Pulmonar/etiología , Embolia Pulmonar/prevención & control , Tromboembolia Venosa/etiología , Tromboembolia Venosa/prevención & controlRESUMEN
Ribosomal RNA (rRNA) transcription by RNA polymerase I (Pol I) is a critical rate-limiting step in ribosome biogenesis, which is essential for cell survival. Despite its global function, disruptions in ribosome biogenesis cause tissue-specific birth defects called ribosomopathies, which frequently affect craniofacial development. Here, we describe a cellular and molecular mechanism underlying the susceptibility of craniofacial development to disruptions in Pol I transcription. We show that Pol I subunits are highly expressed in the neuroepithelium and neural crest cells (NCCs), which generate most of the craniofacial skeleton. High expression of Pol I subunits sustains elevated rRNA transcription in NCC progenitors, which supports their high tissue-specific levels of protein translation, but also makes NCCs particularly sensitive to rRNA synthesis defects. Consistent with this model, NCC-specific deletion of Pol I subunits Polr1a, Polr1c, and associated factor Tcof1 in mice cell-autonomously diminishes rRNA synthesis, which leads to p53 protein accumulation, resulting in NCC apoptosis and craniofacial anomalies. Furthermore, compound mutations in Pol I subunits and associated factors specifically exacerbate the craniofacial anomalies characteristic of the ribosomopathies Treacher Collins syndrome and Acrofacial Dysostosis-Cincinnati type. Mechanistically, we demonstrate that diminished rRNA synthesis causes an imbalance between rRNA and ribosomal proteins. This leads to increased binding of ribosomal proteins Rpl5 and Rpl11 to Mdm2 and concomitantly diminished binding between Mdm2 and p53. Altogether, our results demonstrate a dynamic spatiotemporal requirement for rRNA transcription during mammalian cranial NCC development and corresponding tissue-specific threshold sensitivities to disruptions in rRNA transcription in the pathogenesis of congenital craniofacial disorders.
Asunto(s)
Anomalías Craneofaciales , ARN Polimerasa I , ARN Ribosómico , Proteínas Ribosómicas , Cráneo , Transcripción Genética , Animales , Anomalías Craneofaciales/genética , Disostosis Mandibulofacial/genética , Ratones , Cresta Neural/embriología , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , ARN Polimerasa I/metabolismo , ARN Ribosómico/genética , Proteínas Ribosómicas/metabolismo , Cráneo/embriología , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
AIMS: Patients' post-operative wellbeing determines the impact and effectiveness of breast reshaping and reconstruction procedures. The aim of the study was to evaluate and compare four different types of breast reconstruction: bilateral therapeutic mammaplasty, DIEP flap, ELD with immediate lipomodelling and implant-based reconstruction using BREAST-Q. METHODS: Patients who underwent breast reconstruction by one of the above-mentioned methods were identified from a retrospective register and sent BREAST-Q questionnaires. Univariate and multivariate analysis of BREAST-Q scores and clinical characteristics were performed for identifying trends between and within groups. RESULTS: A total of 240 patients were identified with a response rate of 57%. Patients receiving implants were statistically less satisfied with breast reconstruction (mean 57%) and tended to be younger with lower BMI in comparison to other groups. There were no statistical differences in psychosocial wellbeing or patient experience between groups. Despite the fact that clinically these groups were heterogeneous, satisfaction with breast was similar in the remaining three autologous groups (range 70-75%). Detailed analysis and interpretation of quality-of-life scores, clinical differences and trends identified in the multivariate analysis along with nuances between surgical techniques used in our unit for breast reshaping and reconstruction, have been performed. CONCLUSIONS: The most important goal of breast reconstruction is to restore patients' quality of life and satisfaction with breast. Identifying factors which can potentially predict poor outcomes will improve the informed consent process and patient selection.
Asunto(s)
Neoplasias de la Mama , Mamoplastia , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mamoplastia/métodos , Mastectomía/métodos , Satisfacción del Paciente , Calidad de Vida , Estudios RetrospectivosRESUMEN
Clefts of the lip and palate (CLP), the major causes of congenital facial malformation globally, result from failure of fusion of the facial processes during embryogenesis. With a prevalence of 1 in 500-2500 live births, CLP causes major morbidity throughout life as a result of problems with facial appearance, feeding, speaking, obstructive apnoea, hearing and social adjustment and requires complex, multi-disciplinary care at considerable cost to healthcare systems worldwide. Long-term outcomes for affected individuals include increased mortality compared with their unaffected siblings. The frequent occurrence and major healthcare burden imposed by CLP highlight the importance of dissecting the molecular mechanisms driving facial development. Identification of the genetic mutations underlying syndromic forms of CLP, where CLP occurs in association with non-cleft clinical features, allied to developmental studies using appropriate animal models is central to our understanding of the molecular events underlying development of the lip and palate and, ultimately, how these are disturbed in CLP.
Asunto(s)
Labio Leporino , Fisura del Paladar , Labio Leporino/complicaciones , Labio Leporino/genética , Fisura del Paladar/complicaciones , Fisura del Paladar/genética , Desarrollo Embrionario/genética , Cara , HumanosRESUMEN
Local blood flow control within the central nervous system (CNS) is critical to proper function and is dependent on coordination between neurons, glia, and blood vessels. Macroglia, such as astrocytes and Müller cells, contribute to this neurovascular unit within the brain and retina, respectively. This study explored the role of microglia, the innate immune cell of the CNS, in retinal vasoregulation, and highlights changes during early diabetes. Structurally, microglia were found to contact retinal capillaries and neuronal synapses. In the brain and retinal explants, the addition of fractalkine, the sole ligand for monocyte receptor Cx3cr1, resulted in capillary constriction at regions of microglial contact. This vascular regulation was dependent on microglial Cx3cr1 involvement, since genetic and pharmacological inhibition of Cx3cr1 abolished fractalkine-induced constriction. Analysis of the microglial transcriptome identified several vasoactive genes, including angiotensinogen, a constituent of the renin-angiotensin system (RAS). Subsequent functional analysis showed that RAS blockade via candesartan abolished microglial-induced capillary constriction. Microglial regulation was explored in a rat streptozotocin (STZ) model of diabetic retinopathy. Retinal blood flow was reduced after 4 wk due to reduced capillary diameter and this was coincident with increased microglial association. Functional assessment showed loss of microglial-capillary response in STZ-treated animals and transcriptome analysis showed evidence of RAS pathway dysregulation in microglia. While candesartan treatment reversed capillary constriction in STZ-treated animals, blood flow remained decreased likely due to dilation of larger vessels. This work shows microglia actively participate in the neurovascular unit, with aberrant microglial-vascular function possibly contributing to the early vascular compromise during diabetic retinopathy.
Asunto(s)
Quimiocina CX3CL1/metabolismo , Retinopatía Diabética/patología , Microglía/fisiología , Retina/patología , Animales , Bencimidazoles/farmacología , Compuestos de Bifenilo/farmacología , Quimiocina CX3CL1/farmacología , Retinopatía Diabética/inducido químicamente , Retinopatía Diabética/metabolismo , Perfilación de la Expresión Génica , Ratones , Microglía/metabolismo , Neuronas/fisiología , Pericitos/patología , Ratas , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/genética , Retina/metabolismo , Vasos Retinianos/efectos de los fármacos , Vasos Retinianos/patología , Transducción de Señal/efectos de los fármacos , Estreptozocina/farmacología , Tetrazoles/farmacología , Vasoconstricción/efectos de los fármacosRESUMEN
BACKGROUND: Accumulation of Foxp3+ regulatory T (Treg) cells in the tumor often represents an important mechanism for cancer immune evasion and a critical barrier to anti-tumor immunity and immunotherapy. Many tumor-infiltrating Treg cells display an activated phenotype and express the transcription factor Blimp1. However, the specific impact of these Blimp1+ Treg cells and their follicular regulatory T (TFR) cell subset on tumor and the underlying mechanisms of action are not yet well-explored. METHODS: Various transplantable tumor models were established in immunocompetent wild-type mice and mice with a Foxp3-specific ablation of Blimp1. Tumor specimens from patients with metastatic melanoma and TCGA datasets were analyzed to support the potential role of Treg and TFR cells in tumor immunity. In vitro culture assays and in vivo adoptive transfer assays were used to understand how Treg, TFR cells and antibody responses influence tumor control. RNA sequencing and NanoString analysis were performed to reveal the transcriptome of tumor-infiltrating Treg cells and tumor cells, respectively. Finally, the therapeutic effects of anti-PD-1 treatment combined with the disruption of Blimp1+ Treg activity were evaluated. RESULTS: Blimp1+ Treg and TFR cells were enriched in the tumors, and higher tumoral TFR signatures indicated increased risk of melanoma metastasis. Deletion of Blimp1 in Treg cells resulted in impaired suppressive activity and a reprogramming into effector T-cells, which were largely restricted to the tumor-infiltrating Treg population. This destabilization combined with increased anti-tumor effector cellular responses, follicular helper T-cell expansion, enhanced tumoral IgE deposition and activation of macrophages secondary to dysregulated TFR cells, remodeled the tumor microenvironment and delayed tumor growth. The increased tumor immunogenicity with MHC upregulation improved response to anti-PD-1 blockade. Mechanistically, Blimp1 enforced intratumoral Treg cells with a unique transcriptional program dependent on Eomesodermin (Eomes) expression; deletion of Eomes in Blimp1-deficient Treg cells restored tumor growth and attenuated anti-tumor immunity. CONCLUSIONS: These findings revealed Blimp1 as a new critical regulator of tumor-infiltrating Treg cells and a potential target for modulating Treg activity to treat cancer. Our study has also revealed two FCERIA-containing immune signatures as promising diagnostic or prognostic markers for melanoma patients.
Asunto(s)
Neoplasias/etiología , Neoplasias/metabolismo , Factor 1 de Unión al Dominio 1 de Regulación Positiva/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Microambiente Tumoral/genética , Microambiente Tumoral/inmunología , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo , Humanos , Inhibidores de Puntos de Control Inmunológico/farmacología , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inmunidad Humoral/genética , Inmunomodulación/efectos de los fármacos , Inmunofenotipificación , Linfocitos Infiltrantes de Tumor/efectos de los fármacos , Linfocitos Infiltrantes de Tumor/inmunología , Linfocitos Infiltrantes de Tumor/metabolismo , Macrófagos/inmunología , Macrófagos/metabolismo , Melanoma Experimental , Ratones , Ratones Noqueados , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Factor 1 de Unión al Dominio 1 de Regulación Positiva/genética , Receptor de Muerte Celular Programada 1/antagonistas & inhibidores , Linfocitos T Reguladores/efectos de los fármacos , Transcriptoma , Resultado del Tratamiento , Microambiente Tumoral/efectos de los fármacosRESUMEN
Regulatory T-cells (Tregs) are important for maintaining self-tolerance and tissue homeostasis. The functional plasticity of Tregs is a key feature of this lineage, as it allows them to adapt to different microenvironments, adopt transcriptional programs reflective of their environments and tailor their suppressive capacity in a context-dependent fashion. Tregs, particularly effector Tregs (eTregs), are abundant in many types of tumors. However, the functional and transcriptional plasticity of eTregs in tumors remain largely to be explored. Although depletion or inhibition of systemic Tregs can enhance anti-tumor responses, autoimmune sequelae have diminished the enthusiasm for such approaches. A more effective approach should specifically target intratumoral Tregs or subvert local Treg-mediated suppression. This mini-review will discuss the reported mechanisms by which the stability and suppressive function of tumoral Tregs are modulated, with the focus on eTregs and a subset of eTregs, follicular regulatory T (TFR) cells, and how to harness this knowledge for the future development of new effective cancer immunotherapies that selectively target the tumor local response while sparing the systemic side effects.
Asunto(s)
Reprogramación Celular , Susceptibilidad a Enfermedades , Neoplasias/etiología , Neoplasias/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Animales , Biomarcadores , Linaje de la Célula , Reprogramación Celular/genética , Reprogramación Celular/inmunología , Humanos , Neoplasias/patología , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismoRESUMEN
Microglia, the resident immune cells of the central nervous system (CNS), were once considered quiescent cells that sat in readiness for reacting to disease and injury. Over the last decade, however, it has become clear that microglia play essential roles in maintaining the normal nervous system. The retina is an easily accessible part of the central nervous system and therefore much has been learned about the function of microglia from studies in the retina and visual system. Anatomically, microglia have processes that contact all synapses within the retina, as well as blood vessels in the major vascular plexuses. Microglia contribute to development of the visual system by contributing to neurogenesis, maturation of cone photoreceptors, as well as refining synaptic contacts. They can respond to neural signals and in turn release a range of cytokines and neurotrophic factors that have downstream consequences on neural function. Moreover, in light of their extensive contact with blood vessels, they are also essential for regulation of vascular development and integrity. This review article summarizes what we have learned about the role of microglia in maintaining the normal visual system and how this has helped in understanding their role in the central nervous system more broadly.
RESUMEN
Genome-wide association studies (GWAS) have generated unprecedented insights into the genetic etiology of orofacial clefting (OFC). The moderate effect sizes of associated noncoding risk variants and limited access to disease-relevant tissue represent considerable challenges for biological interpretation of genetic findings. As rare variants with stronger effect sizes are likely to also contribute to OFC, an alternative approach to delineate pathogenic mechanisms is to identify private mutations and/or an increased burden of rare variants in associated regions. This report describes a framework for targeted resequencing at selected noncoding risk loci contributing to nonsyndromic cleft lip with/without cleft palate (nsCL/P), the most frequent OFC subtype. Based on GWAS data, we selected three risk loci and identified candidate regulatory regions (CRRs) through the integration of credible SNP information, epigenetic data from relevant cells/tissues, and conservation scores. The CRRs (total 57 kb) were resequenced in a multiethnic study population (1061 patients; 1591 controls), using single-molecule molecular inversion probe technology. Combining evidence from in silico variant annotation, pedigree- and burden analyses, we identified 16 likely deleterious rare variants that represent new candidates for functional studies in nsCL/P. Our framework is scalable and represents a promising approach to the investigation of additional congenital malformations with multifactorial etiology.