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1.
Clin Oncol (R Coll Radiol) ; 35(12): e708-e719, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37741712

RESUMO

AIMS: To describe the prevalence of cardiovascular disease (CVD), multiple comorbidities and social deprivation in patients with a potentially curable cancer in 20 English Cancer Alliances. MATERIALS AND METHODS: This National Registry Dataset Analysis used national cancer registry data and CVD databases to describe rates of CVD, comorbidities and social deprivation in patients diagnosed with a potentially curable malignancy (stage I-III breast cancer, stage I-III colon cancer, stage I-III rectal cancer, stage I-III prostate cancer, stage I-IIIA non-small cell lung cancer, stage I-IV diffuse large B-cell lymphoma, stage I-IV Hodgkin lymphoma) between 2013 and 2018. Outcome measures included observation of CVD prevalence, other comorbidities (evaluated by the Charlson Comorbidity Index) and deprivation (using the Index of Multiple Deprivation) according to tumour site and allocation to Cancer Alliance. Patients were allocated to CVD prevalence tertiles (minimum: <33.3rd percentile; middle: 33.3rd to 66.6th percentile; maximum: >66.6th percentile). RESULTS: In total, 634 240 patients with a potentially curable malignancy were eligible. The total CVD prevalence for all cancer sites varied between 13.4% (CVD n = 2058; 95% confidence interval 12.8, 13.9) and 19.6% (CVD n = 7818; 95% confidence interval 19.2, 20.0) between Cancer Alliances. CVD prevalence showed regional variation both for male (16-26%) and female patients (8-16%) towards higher CVD prevalence in northern Cancer Alliances. Similar variation was observed for social deprivation, with the proportion of cancer patients being identified as most deprived varying between 3.3% and 32.2%, depending on Cancer Alliance. The variation between Cancer Alliance for total comorbidities was much smaller. CONCLUSION: Social deprivation, CVD and other comorbidities in patients with a potentially curable malignancy in England show significant regional variations, which may partly contribute to differences observed in treatments and outcomes.


Assuntos
Neoplasias da Mama , Carcinoma Pulmonar de Células não Pequenas , Doenças Cardiovasculares , Neoplasias do Colo , Neoplasias Pulmonares , Neoplasias Retais , Humanos , Masculino , Feminino , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Neoplasias Pulmonares/epidemiologia , Comorbidade , Inglaterra/epidemiologia , Doenças Cardiovasculares/epidemiologia , Neoplasias da Mama/epidemiologia , Neoplasias do Colo/epidemiologia , Privação Social , Sistema de Registros
2.
iScience ; 26(8): 107257, 2023 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-37520696

RESUMO

Mechanisms of infection and pathogenesis have predominantly been studied based on differential gene or protein expression. Less is known about posttranslational modifications, which are essential for protein functional diversity. We applied an innovative glycoproteomics method to study the systemic proteome-wide glycosylation in response to infection. The protein site-specific glycosylation was characterized in plasma derived from well-defined controls and patients. We found 3862 unique features, of which we identified 463 distinct intact glycopeptides, that could be mapped to more than 30 different proteins. Statistical analyses were used to derive a glycopeptide signature that enabled significant differentiation between patients with a bacterial or viral infection. Furthermore, supported by a machine learning algorithm, we demonstrated the ability to identify the causative pathogens based on the distinctive host blood plasma glycopeptide signatures. These results illustrate that glycoproteomics holds enormous potential as an innovative approach to improve the interpretation of relevant biological changes in response to infection.

3.
Nephrol Dial Transplant ; 38(3): 599-609, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35945682

RESUMO

BACKGROUND: Common genetic variants of the enzymes and efflux pump involved in tacrolimus disposition have been associated with calcineurin inhibitor nephrotoxicity, but their importance is unclear because of the multifactorial background of renal fibrosis. This study explores the pro-fibrotic response of tacrolimus exposure in relation to the differential capacity for tacrolimus metabolism in proximal tubule cells (PTCs) with a variable (pharmaco)genetic background. METHODS: PTCs were obtained from protocol allograft biopsies with different combinations of CYP3A5 and ABCB1 variants and were incubated with tacrolimus within the concentration range found in vivo. Gene and protein expression, CYP3A5 and P-glycoprotein function, and tacrolimus metabolites were measured in PTC. Connective tissue growth factor (CTGF) expression was assessed in protocol biopsies of kidney allograft recipients. RESULTS: PTCs produce CTGF in response to escalating tacrolimus exposure, which is approximately 2-fold higher in cells with the CYP3A5*1 and ABCB1 TT combination in vitro. Increasing tacrolimus exposure results in relative higher generation of the main tacrolimus metabolite {13-O-desmethyl tacrolimus [M1]} in cells with this same genetic background. Protocol biopsies show a larger increase in in vivo CTGF tissue expression over time in TT vs. CC/CT but was not affected by the CYP3A5 genotype. CONCLUSIONS: Tacrolimus exposure induces a pro-fibrotic response in a PTC model in function of the donor pharmacogenetic background associated with tacrolimus metabolism. This finding provides a mechanistic insight into the nephrotoxicity associated with tacrolimus treatment and offers opportunities for a tailored immunosuppressive treatment.


Assuntos
Nefropatias , Transplante de Rim , Humanos , Tacrolimo , Citocromo P-450 CYP3A/genética , Imunossupressores/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Genótipo , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética
4.
Kidney Int ; 101(6): 1107-1109, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35597589

RESUMO

Hemolytic uremic syndrome can be initiated by Escherichia coli infections (Shiga-toxin-producing enterohemorrhagic Escherichia coli hemolytic uremic syndrome). When hemoglobin and heme released from ruptured erythrocytes interact with the kidney cells, this can result in platelet activation, vascular inflammation and occlusion, and kidney injury. Pirschel et al. now report that in the absence of protective mechanisms against free hemoglobin and heme, heme-induced kidney injury can be exacerbated. Therapeutic strategies should therefore also target heme-mediated deleterious effects in (severely ill) patients with Shiga-toxin-producing enterohemorrhagic Escherichia coli hemolytic uremic syndrome.


Assuntos
Infecções por Escherichia coli , Síndrome Hemolítico-Urêmica , Escherichia coli Shiga Toxigênica , Infecções por Escherichia coli/complicações , Infecções por Escherichia coli/tratamento farmacológico , Heme/uso terapêutico , Síndrome Hemolítico-Urêmica/terapia , Humanos , Rim , Toxina Shiga/uso terapêutico
5.
Rev Mal Respir ; 39(4): 334-343, 2022 Apr.
Artigo em Francês | MEDLINE | ID: mdl-35289288

RESUMO

Acute Respiratory Infections (ARI) need be better understood and more effectively treated, especially insofar as they are of pivotal importance in public health, particularly during a crisis such as the SARS-CoV2 pandemic. The prospective, multicentric cohort study of viral codetections in respiratory samples study known as ECOVIR was conducted in Normandy, France during two winters (2018-2019, 2019-2020). The objective of the project was to create a biobank of respiratory tract samples from patients consulting their general practitioner (GP) for ARI symptoms. ECOVIR involved 36 GP investigators (GPI), from 8 health care centers throughout Normandy. Six hundred and eighty-five patients with ARI symptoms were included; naso-pharyngeal samples were taken by the GPIs and subsequently analyzed in virology laboratories for the purposes of viral codetection. The median of inclusions was 16 patients for each of the 31 actively participating GPIs over the two winters (CI25-75% [4.75; 27]). By D7, 92% of the patients contacted had responded to our call for participation, enabling us to obtain clinical, environmental and socio-demographic data. Through this study, we created an original functional network, thereby establishing a viable link between research and primary care, which is generally underrepresented in research protocols, even though it constitutes the cornerstone of the French health care system, especially during this prolonged period of sanitary crisis.


Assuntos
COVID-19 , Infecções Respiratórias , COVID-19/epidemiologia , Estudos de Coortes , Hospitais , Humanos , Atenção Primária à Saúde , Estudos Prospectivos , RNA Viral , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/epidemiologia , SARS-CoV-2
6.
Nephrol Dial Transplant ; 37(12): 2457-2473, 2022 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-35099015

RESUMO

BACKGROUND: Unilateral nephrectomy is a relatively common procedure in children which results in a solitary functioning kidney (SFK). Living with an SFK predisposes to kidney injury, but it remains unknown which children are most at risk. We aimed to investigate kidney injury rates in patients who underwent unilateral nephrectomy in childhood and to investigate differences among nephrectomies performed for a congenital anomaly, malignancy or other condition. METHODS: MEDLINE and EMBASE were searched for studies reporting kidney injury rates [i.e. proteinuria, hypertension and/or a decreased glomerular filtration rate (GFR)] of patients who underwent unilateral nephrectomy during childhood. Studies including five or more patients with at least 12 months of follow-up were eligible. Analyses were performed using random effects models and stratified by indication for nephrectomy. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines were used for reporting. RESULTS: Over 5000 unique articles were screened, of which 53 studies reporting on >4000 patients were included in the analyses. Proteinuria, hypertension and a decreased GFR were present in 15.3, 14.5 and 11.9% of patients, respectively. Heterogeneity among the studies was large in several subgroups, impairing quantitative meta-analyses. However, none of our analyses indicated differences in injury rates between a congenital anomaly or malignancy as an indication for nephrectomy. CONCLUSIONS: Unilateral nephrectomy during childhood results in signs of kidney injury in >10% of patients, with no clear difference between the indications for nephrectomy. Therefore, structured follow-up is necessary in all children who underwent nephrectomy, regardless of the indication.


Assuntos
Hipertensão , Nefrectomia , Humanos , Nefrectomia/efeitos adversos , Nefrectomia/métodos , Rim , Proteinúria/epidemiologia , Proteinúria/etiologia , Hipertensão/etiologia
7.
ESMO Open ; 7(1): 100363, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35026723

RESUMO

BACKGROUND: We modeled the clinical course of a cohort of diffuse large B-cell lymphoma (DLBCL) patients with no prior cardiovascular diseases (CVDs) using a multistate modeling framework. PATIENTS AND METHODS: Data on 2600 patients with DLBCL diagnosed between 2000 and 2018 and had received chemotherapy with or without radiotherapy were obtained from a population-wide electronic health database of Hong Kong. We used the Markov illness-death model to quantify the impact of doxorubicin and various risk factors (therapeutic exposure, demographic, comorbidities, cardiovascular risk factors, and lifestyle factors which included smoking) on the clinical course of DLBCL (transitions into incident CVD, lymphoma death, and other causes of death). RESULTS: A total of 613 (23.6%) and 230 (8.8%) of 2600 subjects died of lymphoma and developed incident CVD, respectively. Median follow-up was 7.0 years (interquartile range 3.8-10.8 years). Older ages [hazard ratio (HR) for >75 versus ≤60 years 1.88; 95% confidence interval (CI) 1.25-2.82 and HR for 61-75 versus ≤60 years 1.60; 95% CI 1.12-2.30], hypertension (HR 4.92; 95% CI 2.61-9.26), diabetes (HR 1.43; 95% CI 1.09-1.87), and baseline use of aspirin (HR 5.30; 95% CI 3.93-7.16) were associated with an increased risk of incident CVD. In a subgroup of anticipated higher-risk patients (aged 61-75 years, smoked, had diabetes, and received doxorubicin), we found that they remained on average 7.9 (95% CI 7.2-8.8) years in the DLBCL state and 0.1 (95% CI 0.0-0.4) years in the CVD state, if they could be followed up for 10 years. The brief time in the CVD state is consistent with the high chance of death in patients who developed CVD. Other causes of death have overtaken DLBCL-related death after about 5 years. CONCLUSIONS: In this Asian population-based cohort, we found that incident CVDs can occur soon after DLBCL treatment and continued to occur throughout survivorship. Clinicians are advised to balance the risks and benefits of treatment choices to minimize the risk of CVD.


Assuntos
Doenças Cardiovasculares , Linfoma Difuso de Grandes Células B , Idoso , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Doxorrubicina/efeitos adversos , Humanos , Linfoma Difuso de Grandes Células B/complicações , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/epidemiologia , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Sobreviventes
8.
Hum Mol Genet ; 31(3): 455-470, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34508573

RESUMO

Age-related macular degeneration (AMD) is a major cause of vision loss among the elderly in the Western world. Genetic variants in the complement factor H (CFH) gene are associated with AMD, but the functional consequences of many of these variants are currently unknown. In this study, we aimed to determine the effect of 64 rare and low-frequency variants in the CFH gene on systemic levels of factor H (FH) and complement activation marker C3bBbP using plasma samples of 252 carriers and 159 non-carriers. Individuals carrying a heterozygous nonsense, frameshift or missense variant in CFH presented with significantly decreased FH levels and significantly increased C3bBbP levels in plasma compared to non-carrier controls. FH and C3bBbP plasma levels were relatively stable over time in samples collected during follow-up visits. Decreased FH and increased C3bBbP concentrations were observed in carriers compared to non-carriers of CFH variants among different AMD stages, with the exception of C3bBbP levels in advanced AMD stages, which were equally high in carriers and non-carriers. In AMD families, FH levels were decreased in carriers compared to non-carriers, but C3bBbP levels did not differ. Rare variants in the CFH gene can lead to reduced FH levels or reduced FH function as measured by increased C3bBbP levels. The effects of individual variants in the CFH gene reported in this study will improve the interpretation of rare and low-frequency variants observed in AMD patients in clinical practice.


Assuntos
Degeneração Macular , Polimorfismo de Nucleotídeo Único , Idoso , Fator H do Complemento/genética , Proteínas do Sistema Complemento/genética , Heterozigoto , Humanos , Degeneração Macular/genética , Mutação de Sentido Incorreto
9.
Biomedicines ; 9(12)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34944623

RESUMO

Shiga toxin (Stx)-producing Escherichia coli (STEC) infection is the most common cause of hemolytic uremic syndrome (HUS), one of the main causes of acute kidney injury in children. Stx plays an important role in endothelium damage and pathogenesis of STEC-HUS. However, the effects of Stx on neutrophils and neutrophil extracellular trap (NET) formation are not well understood. In this study, we investigated how Stx2a affects NET formation and NETotic pathways (NADPH or NOX-dependent and -independent) using neutrophils isolated from healthy donors and patients with STEC-HUS, during the acute and recovery phase of the disease. Stx2a dose-dependently induced NETosis in neutrophils isolated from both healthy controls and STEC-HUS patients. NETosis kinetics and mechanistic data with pathway-specific inhibitors including diphenyleneiodonium (DPI)-, ERK-, and P38-inhibitors showed that Stx2a-induced NETosis via the NOX-dependent pathway. Neutrophils from STEC-HUS patients in the acute phase showed less ROS and NETs formation compared to neutrophils of the recovery phase of the disease and in healthy controls. NETs induced by Stx2a may lead to the activation of endothelial cells, which might contribute to the manifestation of thrombotic microangiopathy in STEC-HUS.

10.
Microorganisms ; 9(10)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34683478

RESUMO

In 90% of the cases, childhood hemolytic uremic syndrome (HUS) is caused by an infection with the Shiga toxin (Stx) producing E. coli bacteria (STEC-HUS). Stx preferentially binds to its receptor, the glycosphingolipid, globotriaosylceramide (Gb3), present on the surface of human kidney cells and various organs. In this study, the glycosphingolipid pathway in endothelial cells was explored as therapeutic target for STEC-HUS. Primary human glomerular microvascular endothelial cells (HGMVECs) and human blood outgrowth endothelial cells (BOECs) in quiescent and activated state were pre-incubated with Eliglustat (Cerdelga®; glucosylceramide synthase inhibitor) or Agalsidase alpha (Replagal®; human cell derived alpha-galactosidase) in combination with various concentrations of Stx2a. Preincubation of endothelial cells with Agalsidase resulted in an increase of α-galactosidase activity in the cell, but had no effect on the binding of Stx to the cell surface when compared to control cells. However, the incubation of both types of endothelial cells incubated with or without the pro-inflammatory cytokine TNFα in combination with Eliglustat resulted in significant decrease of Stx binding to the cell surface, a decrease in protein synthesis by Stx2a, and diminished cellular Gb3 levels as compared to control cells. In conclusion, inhibition of the synthesis of Gb3 may be a potential future therapeutic target to protect against (further) endothelial damage caused by Stx.

11.
Ecotoxicol Environ Saf ; 225: 112720, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34509163

RESUMO

The last remaining population of European sturgeon (Acipenser sturio) lives in the Gironde-Garonne-Dordogne (France) catchment (GGD). Captive young individuals are released into the GGD hydrosystem each year, as part of a restocking programme. This study aims to assess the health status of juveniles A. sturio to current conditions in the GGD hydrosystem, to evaluate their capacity to survive and grow in a moderately anthropized ecosystems. 3-month-old farmed sturgeons were exposed for one month in experimental conditions that mimic the environmental conditions in the Garonne and Dordogne rivers, followed by five months of depuration. After one month of exposure, fish exposed to Dordogne and Garonne waters bioaccumulated higher levels of metals and persistent organic pollutants, displayed a reduced hepato-somatic index, and had depleted levels of lipids and glycogen content in their liver, when compared with the Reference group. However, metabolic and swimming performance, as well as the costs of swimming were not impaired. After the 5 months depuration, a significant decrease of K was observed for all exposure conditions. HSI also decreased with time. The overall health status and adaptive capacity of juvenile A. sturio appeared to be maintained over the experimental 6 months' period. Juveniles of A. sturio seem to have the adaptive capacity to survive and grow in the GGD hydrosystem, after being released as part of a restocking programme.


Assuntos
Poluentes Orgânicos Persistentes , Rios , Animais , Ecossistema , Peixes , Humanos , Lactente , Metais
12.
Int J Mol Sci ; 22(11)2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-34070679

RESUMO

Hemolytic uremic syndrome (HUS) is characterized by a triad of symptoms consisting of hemolytic anemia, thrombocytopenia and acute renal failure. The most common form of HUS is caused by an infection with Shiga toxin (Stx) producing Escherichia coli bacteria (STEC-HUS), and the kidneys are the major organs affected. The development of HUS after an infection with Stx occurs most frequently in children under the age of 5 years. However, the cause for the higher incidence of STEC-HUS in children compared to adults is still not well understood. Human glomerular microvascular endothelial cells (HGMVECs) isolated and cultured from pediatric and adult kidney tissue were investigated with respect to Stx binding and different cellular responses. Shiga toxin-1 (Stx-1) inhibited protein synthesis in both pediatric and adult HGMVECs in a dose-dependent manner at basal conditions. The preincubation of pediatric and adult HGMVECs for 24 hrs with TNFα resulted in increased Stx binding to the cell surface and a 20-40% increase in protein synthesis inhibition in both age groups. A decreased proliferation of cells was found when a bromodeoxyuridine (BrdU) assay was performed. A trend towards a delay in endothelial wound closure was visible when pediatric and adult HGMVECs were incubated with Stx-1. Although minor differences between pediatric HGMVECs and adult HGMVECs were found in the assays applied in this study, no significant differences were observed. In conclusion, we have demonstrated that in vitro primary HGMVECs isolated from pediatric and adult kidneys do not significantly differ in their cell biological responses to Stx-1.


Assuntos
Células Endoteliais/metabolismo , Mesângio Glomerular/metabolismo , Microvasos/metabolismo , Toxina Shiga I/toxicidade , Adulto , Células Cultivadas , Pré-Escolar , Relação Dose-Resposta a Droga , Células Endoteliais/patologia , Feminino , Mesângio Glomerular/patologia , Humanos , Masculino , Microvasos/patologia
13.
Sci Robot ; 6(52)2021 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-34043549

RESUMO

Future developments in micromanufacturing will require advances in micromanipulation tools. Several robotic micromanipulation methods have been developed to position micro-objects mostly in air and in liquids. The air-water interface is a third medium where objects can be manipulated, offering a good compromise between the two previously mentioned ones. Objects at the interface are not subjected to stick-slip due to dry friction in air and profit from a reduced drag compared with those in water. Here, we present the ThermoBot, a microrobotic platform dedicated to the manipulation of objects placed at the air-water interface. For actuation, ThermoBot uses a laser-induced thermocapillary flow, which arises from the surface stress caused by the temperature gradient at the fluid interface. The actuated objects can reach velocities up to 10 times their body length per second without any on-board actuator. Moreover, the localized nature of the thermocapillary flow enables the simultaneous and independent control of multiple objects, thus paving the way for microassembly operations at the air-water interface. We demonstrate that our setup can be used to direct capillary-based self-assemblies at this interface. We illustrate the ThermoBot's capabilities through three examples: simultaneous control of up to four spheres, control of complex objects in both position and orientation, and directed self-assembly of multiple pieces.

14.
PLoS One ; 16(4): e0250996, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33930094

RESUMO

The calcineurin inhibitors (CNI) cyclosporine A and tacrolimus comprise the basis of immunosuppressive regimes in all solid organ transplantation. However, long-term or high exposure to CNI leads to histological and functional renal damage (CNI-associated nephrotoxicity). In the kidney, proximal tubule cells are the only cells that metabolize CNI and these cells are believed to play a central role in the origin of the toxicity for this class of drugs, although the underlying mechanisms are not clear. Several studies have reported oxidative stress as an important mediator of CNI-associated nephrotoxicity in response to CNI exposure in different available proximal tubule cell models. However, former models often made use of supra-therapeutic levels of tissue drug exposure. In addition, they were not shown to express the relevant enzymes (e.g., CYP3A5) and transporters (e.g., P-glycoprotein) for the metabolism of CNI in human proximal tubule cells. Moreover, the used methods for detecting ROS were potentially prone to false positive results. In this study, we used a novel proximal tubule cell model established from human allograft biopsies that demonstrated functional expression of relevant enzymes and transporters for the disposition of CNI. We exposed these cells to CNI concentrations as found in tissue of stable solid organ transplant recipients with therapeutic blood concentrations. We measured the glutathione redox balance in this cell model by using organelle-targeted variants of roGFP2, a highly sensitive green fluorescent reporter protein that dynamically equilibrates with the glutathione redox couple through the action of endogenous glutaredoxins. Our findings provide evidence that CNI, at concentrations commonly found in allograft biopsies, do not alter the glutathione redox balance in mitochondria, peroxisomes, and the cytosol. However, at supra-therapeutic concentrations, cyclosporine A but not tacrolimus increases the ratio of oxidized/reduced glutathione in the mitochondria, suggestive of imbalances in the redox environment.


Assuntos
Inibidores de Calcineurina/farmacologia , Glutationa/metabolismo , Túbulos Renais Proximais/efeitos dos fármacos , Rim/efeitos dos fármacos , Transplante de Órgãos/métodos , Células Cultivadas , Ciclosporina/farmacologia , Rejeição de Enxerto/prevenção & controle , Humanos , Rim/metabolismo , Rim/patologia , Túbulos Renais Proximais/metabolismo , Oxirredução , Tacrolimo/farmacologia
15.
Prog Retin Eye Res ; 84: 100952, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33610747

RESUMO

Age-related macular degeneration (AMD) is the main cause of vision loss among the elderly in the Western world. While AMD is a multifactorial disease, the complement system was identified as one of the main pathways contributing to disease risk. The strong link between the complement system and AMD was demonstrated by genetic associations, and by elevated complement activation in local eye tissue and in the systemic circulation of AMD patients. Several complement inhibitors have been and are being explored in clinical trials, but thus far with limited success, leaving the majority of AMD patients without treatment options to date. This indicates that there is still a gap of knowledge regarding the functional implications of the complement system in AMD pathogenesis and how to bring these towards clinical translation. Many different experimental set-ups and disease models have been used to study complement activation in vivo and in vitro, and recently emerging patient-derived induced pluripotent stem cells and genome-editing techniques open new opportunities to study AMD disease mechanisms and test new therapeutic strategies in the future. In this review we provide an extensive overview of methods employed to understand the molecular processes of complement activation in AMD pathogenesis. We discuss the findings, advantages and challenges of each approach and conclude with an outlook on how recent, exciting developments can fill in current knowledge gaps and can aid in the development of effective complement-targeting therapeutic strategies in AMD.


Assuntos
Degeneração Macular , Idoso , Ativação do Complemento , Proteínas do Sistema Complemento/genética , Variação Genética , Humanos , Degeneração Macular/genética
16.
Front Immunol ; 12: 789897, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35069568

RESUMO

Complement factor I (FI) is a central inhibitor of the complement system, and impaired FI function increases complement activation, contributing to diseases such as age-related macular degeneration (AMD) and atypical hemolytic uremic syndrome (aHUS). Genetic variation in complement factor I (CFI) has been identified in both AMD and aHUS, with more than half of these variants leading to reduced FI secretion levels. For many of the variants with normal FI secretion, however, functional implications are not yet known. Here we studied 11 rare missense variants, with FI secretion levels comparable to wildtype, but a predicted damaging effects based on the Combined Annotation Dependent Depletion (CADD) score. Three variants (p.Pro50Ala, p.Arg339Gln, and p.Ser570Thr) were analyzed in plasma and serum samples of carriers affected by AMD. All 11 variants (nine for the first time in this study) were recombinantly expressed and the ability to degrade C3b was studied with the C3b degradation assay. The amount of degradation was determined by measuring the degradation product iC3b with ELISA. Eight of 11 (73%) mutant proteins (p.Pro50Ala, p.Arg339Gln, p.Ile340Thr, p.Gly342Glu, p.Gly349Arg, p.Arg474Gln, p.Gly487Cys, and p.Gly512Ser) showed significantly impaired C3b degradation, and were therefore classified as likely pathogenic. Our data indicate that genetic variants in CFI with a CADD score >20 are likely to affect FI function, and that monitoring iC3b in a degradation assay is a useful tool to establish the pathogenicity of CFI variants in functional studies.


Assuntos
Síndrome Hemolítico-Urêmica Atípica , Fator I do Complemento , Degeneração Macular , Mutação de Sentido Incorreto , Substituição de Aminoácidos , Síndrome Hemolítico-Urêmica Atípica/sangue , Síndrome Hemolítico-Urêmica Atípica/genética , Síndrome Hemolítico-Urêmica Atípica/imunologia , Complemento C3b/imunologia , Complemento C3b/metabolismo , Fator I do Complemento/genética , Fator I do Complemento/imunologia , Fator I do Complemento/metabolismo , Feminino , Humanos , Degeneração Macular/sangue , Degeneração Macular/genética , Degeneração Macular/imunologia , Masculino
17.
Clin Microbiol Infect ; 27(6): 878-885, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32896653

RESUMO

OBJECTIVES: Protection induced by acellular vaccines can be short, requiring novel immunization strategies. Objectives of this study were to evaluate safety and capacity of a recombinant pertussis toxin (PTgen) -coated Viaskin® epicutaneous patch to recall memory responses in healthy adults. METHODS: This double-blind, placebo-controlled randomized trial (Phase I) assessed the safety and immunogenicity of PTgen administered on days 0 and 14 to healthy adults using Viaskin® patches applied directly or after epidermal laser-based skin preparation. Patch administration was followed by Boostrix®dTpa on day 42. Antibodies were assessed at days 0, 14, 28, 42 and 70. RESULTS: Among 102 volunteers enrolled, 80 received Viaskin-PT (Viaskin-PT 25 µg (n = 25), Viaskin-PT 50 µg (n = 25), laser + Viaskin-PT 25 µg (n = 5), laser + Viaskin-PT 50 µg (n = 25)), Viaskin-placebo (n = 10) or laser + Viaskin-placebo (n = 2). Incidence of adverse events was similar across groups (any local event: 21/25 (84.0%), 24/25 (96.0%), 4/5 (80.0%), 24/25 (96.0%), 8/10 (80.0%), 10/12 (83.0%), respectively). Direct application induced no detectable response. On day 42, PT-IgG geometric mean concentrations were significantly higher following laser + Viaskin-PT 25 µg and 50 µg (139.87 (95% CI 87.30-224.10) and 121.76 (95% CI 95.04-156.00), respectively), than laser + Viaskin-placebo (59.49, 95% CI 39.37-89.90). Seroresponse rates were higher following laser + Viaskin-PT 25 µg (4/5 (80.0%), 95% CI 28.4-99.5) and 50 µg (22/25 (88.0%), 95% CI 68.8-97.5) than laser + Viaskin-placebo (0/12 (0.0%), 95% CI 0.0-26.5). CONCLUSIONS: Viaskin-PT applied after laser-based epidermal skin preparation showed encouraging safety and immunogenicity results: anti-PT booster responses were not inferior to those elicited by Boostrix®dTpa. This study is registered at ClinicalTrials.gov (NCT03035370) and was funded by DBV Technologies.


Assuntos
Toxina Pertussis/imunologia , Administração Cutânea , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Anticorpos Antibacterianos/imunologia , Método Duplo-Cego , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Masculino , Toxina Pertussis/administração & dosagem , Adulto Jovem
18.
Clin Transl Immunology ; 9(12): e1225, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33318796

RESUMO

OBJECTIVES: Complement deficiencies are difficult to diagnose because of the variability of symptoms and the complexity of the diagnostic process. Here, we applied a novel 'complementomics' approach to study the impact of various complement deficiencies on circulating complement levels. METHODS: Using a quantitative multiplex mass spectrometry assay, we analysed 44 peptides to profile 34 complement proteins simultaneously in 40 healthy controls and 83 individuals with a diagnosed deficiency or a potential pathogenic variant in 14 different complement proteins. RESULTS: Apart from confirming near or total absence of the respective protein in plasma of complement-deficient patients, this mass spectrometry-based profiling method led to the identification of additional deficiencies. In many cases, partial depletion of the pathway up- and/or downstream of the absent protein was measured. This was especially found in patients deficient for complement inhibitors, such as angioedema patients with a C1-inhibitor deficiency. The added value of complementomics was shown in three patients with poorly defined complement deficiencies. CONCLUSION: Our study shows the potential clinical utility of profiling circulating complement proteins as a comprehensive read-out of various complement deficiencies. Particularly, our approach provides insight into the intricate interplay between complement proteins due to functional coupling, which contributes to the better understanding of the various disease phenotypes and improvement of care for patients with complement-mediated diseases.

19.
Toxins (Basel) ; 12(8)2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32751286

RESUMO

Hemolytic uremic syndrome (HUS) is a rare disease primarily characterized by hemolytic anemia, thrombocytopenia, and acute renal failure. Endothelial damage is the hallmark of the pathogenesis of HUS with an infection with the Shiga toxin (Stx) producing Escherichia coli (STEC-HUS) as the main underlying cause in childhood. In this study, blood outgrowth endothelial cells (BOECs) were isolated from healthy donors serving as controls and patients recovered from STEC-HUS. We hypothesized that Stx is more cytotoxic for STEC-HUS BOECs compared to healthy donor control BOECs explained via a higher amount of Stx bound to the cell surface. Binding of Shiga toxin-2a (Stx2a) was investigated and the effect on cytotoxicity, protein synthesis, wound healing, and cell proliferation was studied in static conditions. Results show that BOECs are highly susceptible for Stx2a. Stx2a is able to bind to the cell surface of BOECs with cytotoxicity in a dose-dependent manner as a result. Pre-treatment with tumor necrosis factor alpha (TNF-α) results in enhanced Stx binding with 20-30% increased lactate dehydrogenase (LDH) release. Endothelial wound healing is delayed in a Stx2a-rich environment; however, this is not caused by an effect on the proliferation rate of BOECs. No significant differences were found between control BOECs and BOECs from recovered STEC-HUS patients in terms of Stx2a binding and inhibition of protein synthesis.


Assuntos
Células Endoteliais/efeitos dos fármacos , Toxina Shiga/toxicidade , Animais , Proliferação de Células , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Chlorocebus aethiops , Síndrome Hemolítico-Urêmica , Humanos , Modelos Biológicos , Escherichia coli Shiga Toxigênica , Células Vero , Cicatrização/efeitos dos fármacos
20.
Hum Mol Genet ; 29(14): 2313-2324, 2020 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-32510551

RESUMO

Factor I (FI) is one of the main inhibitors of complement activity, and numerous rare coding variants have been reported in patients with age-related macular degeneration, atypical hemolytic uremic syndrome and C3 glomerulopathy. Since many of these variants are of unknown clinical significance, this study aimed to determine the effect of rare coding variants in the complement factor I (CFI) gene on FI expression. We measured FI levels in plasma samples of carriers of rare coding variants and in vitro in the supernatants of epithelial cells expressing recombinant FI. FI levels were measured in 177 plasma samples of 155 individuals, carrying 24 different rare coding variants in CFI. In carriers of the variants p.Gly119Arg, p.Leu131Arg, p.Gly188Ala and c.772G>A (r.685_773del), significantly reduced FI plasma levels were detected. Furthermore, recombinant FI expression levels were determined for 126 rare coding variants. Of these variants 68 (54%) resulted in significantly reduced FI expression in supernatant compared to wildtype (WT). The recombinant protein expression levels correlated significantly with the FI level in plasma of carriers of CFI variants. In this study, we performed the most comprehensive FI expression level analysis of rare coding variants in CFI to date. More than half of CFI variants lead to reduced FI expression, which might impair complement regulation in vivo. Our study will aid the interpretation of rare coding CFI variants identified in clinical practice, which is in particular important in light of patient inclusion in ongoing clinical trials for CFI gene supplementation in AMD.


Assuntos
Síndrome Hemolítico-Urêmica Atípica/genética , Fator I do Complemento/genética , Fibrinogênio/genética , Degeneração Macular/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Síndrome Hemolítico-Urêmica Atípica/sangue , Síndrome Hemolítico-Urêmica Atípica/patologia , Feminino , Regulação da Expressão Gênica/genética , Predisposição Genética para Doença , Genótipo , Heterozigoto , Humanos , Degeneração Macular/sangue , Degeneração Macular/patologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
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