RESUMO
A growing body of evidence suggests that aggregated α-synuclein, the major constituent of Lewy bodies, plays a key role in the pathogenesis of Parkinson's disease and related α-synucleinopathies. Immunotherapies, both active and passive, against α-synuclein have been developed and are promising novel treatment strategies for such disorders. Here, we report on the humanization and pharmacological characteristics of ABBV-0805, a monoclonal antibody that exhibits a high selectivity for human aggregated α-synuclein and very low affinity for monomers. ABBV-0805 binds to a broad spectrum of soluble aggregated α-synuclein, including small and large aggregates of different conformations. Binding of ABBV-0805 to pathological α-synuclein was demonstrated in Lewy body-positive post mortem brains of Parkinson's disease patients. The functional potency of ABBV-0805 was demonstrated in several cellular assays, including Fcγ-receptor mediated uptake of soluble aggregated α-synuclein in microglia and inhibition of neurotoxicity in primary neurons. In vivo, the murine version of ABBV-0805 (mAb47) displayed significant dose-dependent decrease of α-synuclein aggregates in brain in several mouse models, both in prophylactic and therapeutic settings. In addition, mAb47 treatment of α-synuclein transgenic mice resulted in a significantly prolonged survival. ABBV-0805 selectively targets soluble toxic α-synuclein aggregates with a picomolar affinity and demonstrates excellent in vivo efficacy. Based on the strong preclinical findings described herein, ABBV-0805 has been progressed into clinical development as a potential disease-modifying treatment for Parkinson's disease.
Assuntos
Anticorpos Monoclonais , Doença de Parkinson , Sinucleinopatias , Animais , Anticorpos Monoclonais/uso terapêutico , Humanos , Longevidade , Camundongos , Camundongos Transgênicos , Doença de Parkinson/metabolismo , Doença de Parkinson/terapia , Sinucleinopatias/terapia , alfa-Sinucleína/metabolismoRESUMO
An updated survival analysis was conducted for the Phase II study O-12-M1 of melphalan flufenamide (melflufen) plus dexamethasone in patients with relapsed/refractory multiple myeloma (RRMM) with two or more prior lines of therapy (including bortezomib and lenalidomide). Partial response or better was seen in 31%. After a 46-month median overall survival (OS) follow-up, melflufen plus dexamethasone had a median OS of 20·7 months (75th percentile OS, 47·5 months). The median time-to-next treatment for melflufen plus dexamethasone was 7·9 months. In summary, melflufen plus dexamethasone resulted in sustained long-term clinical benefit in patients with RRMM.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Mieloma Múltiplo , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Feminino , Seguimentos , Humanos , Masculino , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Melfalan/análogos & derivados , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/mortalidade , Fenilalanina/administração & dosagem , Fenilalanina/efeitos adversos , Fenilalanina/análogos & derivados , Taxa de SobrevidaRESUMO
BACKGROUND: Due to its neurotoxic properties, oligomeric alpha-synuclein (α-syn) has been suggested as an attractive target for passive immunization against Parkinson's disease (PD). In mouse models of PD, antibody treatment has been shown to lower the levels of pathogenic α-syn species, including oligomers, although the mechanisms of action remain unknown. We have previously shown that astrocytes rapidly engulf α-syn oligomers that are intracellularly stored, rather than degraded, resulting in impaired mitochondria. METHODS: The aim of the present study was to investigate if the accumulation of α-syn in astrocytes can be affected by α-syn oligomer-selective antibodies. Co-cultures of astrocytes, neurons, and oligodendrocytes were derived from embryonic mouse cortex and exposed to α-syn oligomers or oligomers pre-incubated with oligomer-selective antibodies. RESULTS: In the presence of antibodies, the astrocytes displayed an increased clearance of the exogenously added α-syn, and consequently, the α-syn accumulation in the culture was markedly reduced. Moreover, the addition of antibodies rescued the astrocytes from the oligomer-induced mitochondrial impairment. CONCLUSIONS: Our results demonstrate that oligomer-selective antibodies can prevent α-syn accumulation and mitochondrial dysfunction in cultured astrocytes.
Assuntos
Anticorpos Monoclonais/farmacologia , Astrócitos/metabolismo , Mitocôndrias/efeitos dos fármacos , alfa-Sinucleína/antagonistas & inibidores , Animais , Corpos de Inclusão , Espaço Intracelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/patologia , Doença de ParkinsonRESUMO
Our prior study utilized both in vitro and in vivo multiple myeloma (MM) xenograft models to show that a novel alkylator melphalan-flufenamide (Melflufen) is a more potent anti-MM agent than melphalan and overcomes conventional drug resistance. Here we examined whether this potent anti-MM activity of melflufen versus melphalan is due to their differential effect on DNA damage and repair signalling pathways via γ-H2AX/ATR/CHK1/Ku80. Melflufen-induced apoptosis was associated with dose- and time-dependent rapid phosphorylation of γ-H2AX. Melflufen induces γ-H2AX, ATR, and CHK1 as early as after 2 h exposure in both melphalan-sensitive and -resistant cells. However, melphalan induces γ-H2AX in melphalan-sensitive cells at 6 h and 24 h; no γ-H2AX induction was observed in melphalan-resistant cells even after 24 h exposure. Similar kinetics was observed for ATR and CHK1 in meflufen- versus melphalan-treated cells. DNA repair is linked to melphalan-resistance; and importantly, we found that melphalan, but not melflufen, upregulates Ku80 that repairs DNA double-strand breaks. Washout experiments showed that a brief (2 h) exposure of MM cells to melflufen is sufficient to initiate an irreversible DNA damage and cytotoxicity. Our data therefore suggest that melflufen triggers a rapid, robust, and an irreversible DNA damage which may account for its ability to overcome melphalan-resistance in MM cells.
Assuntos
Apoptose/efeitos dos fármacos , Dano ao DNA , Melfalan/análogos & derivados , Mieloma Múltiplo/patologia , Fenilalanina/análogos & derivados , Antineoplásicos Alquilantes/farmacologia , Reparo do DNA/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Histonas/metabolismo , Humanos , Cinética , Melfalan/farmacologia , Mieloma Múltiplo/tratamento farmacológico , Fenilalanina/farmacologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Células Tumorais CultivadasRESUMO
PURPOSE: Melflufen (melphalan flufenamide, previously designated J1) is an optimized and targeted derivative of melphalan, hydrolyzed by aminopeptidases overexpressed in tumor cells resulting in selective release and trapping of melphalan, and enhanced activity in preclinical models. METHODS: This was a prospective, single-armed, open-label, first-in-human, dose-finding phase I/IIa study in 45 adult patients with advanced and progressive solid tumors without standard treatment options. Most common tumor types were ovarian carcinoma (n = 20) and non-small-cell lung cancer (NSCLC, n = 11). RESULTS: In the dose-escalating phase I part of the study, seven patients were treated with increasing fixed doses of melflufen (25-130 mg) Q3W. In the subsequent phase IIa part, 38 patients received in total 115 cycles of therapy at doses of 30-75 mg. No dose-limiting toxicities (DLTs) were observed at 25 and 50 mg; at higher doses DLTs were reversible neutropenias and thrombocytopenias, particularly evident in heavily pretreated patients, and the recommended phase II dose (RPTD) was set to 50 mg. Response Evaluation Criteria In Solid Tumors (RECIST) evaluation after 3 cycles of therapy (27 patients) showed partial response in one (ovarian cancer), and stable disease in 18 patients. One NSCLC patient received nine cycles of melflufen and progressed after 7 months of therapy. CONCLUSIONS: In conclusion, melflufen can safely be given to cancer patients, and the toxicity profile was as expected for alkylating agents; RPTD is 50 mg Q3W. Reversible and manageable bone marrow suppression was identified as a DLT. Clinical activity is suggested in ovarian cancer, but modest activity in treatment of refractory NSCLC.
Assuntos
Antineoplásicos Alquilantes/administração & dosagem , Melfalan/análogos & derivados , Neoplasias/tratamento farmacológico , Fenilalanina/análogos & derivados , Adulto , Idoso , Idoso de 80 Anos ou mais , Alquilação/efeitos dos fármacos , Alquilação/fisiologia , Antineoplásicos Alquilantes/efeitos adversos , Progressão da Doença , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Pessoa de Meia-Idade , Neoplasias/diagnóstico , Peptídeo Hidrolases/metabolismo , Fenilalanina/administração & dosagem , Fenilalanina/efeitos adversos , Estudos ProspectivosRESUMO
Several lines of evidence suggest that accumulation of aggregated alpha-synuclein (α-synuclein) in the central nervous system (CNS) is an early pathogenic event in Parkinson's disease and other Lewy body disorders. In recent years, animal studies have indicated immunotherapy with antibodies directed against α-synuclein as a promising novel treatment strategy. Since large α-synuclein oligomers, or protofibrils, have been demonstrated to possess pronounced cytotoxic properties, such species should be particularly attractive as therapeutic targets. In support of this, (Thy-1)-h[A30P] α-synuclein transgenic mice with motor dysfunction symptoms were found to display increased levels of α-synuclein protofibrils in the CNS. An α-synuclein protofibril-selective monoclonal antibody (mAb47) was evaluated in this α-synuclein transgenic mouse model. As measured by ELISA, 14month old mice treated for 14weeks with weekly intraperitoneal injections of mAb47 displayed significantly lower levels of both soluble and membrane-associated protofibrils in the spinal cord. Besides the lower levels of pathogenic α-synuclein demonstrated, a reduction of motor dysfunction in transgenic mice upon peripheral administration of mAb47 was indicated. Thus, immunotherapy with antibodies targeting toxic α-synuclein species holds promise as a future disease-modifying treatment in Parkinson's disease and related disorders.
Assuntos
Anticorpos Monoclonais/uso terapêutico , Imunização Passiva , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/terapia , alfa-Sinucleína/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Encéfalo/imunologia , Encéfalo/patologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Injeções Intraperitoneais , Masculino , Camundongos Transgênicos , Atividade Motora/fisiologia , Mutação , Transtornos Parkinsonianos/imunologia , Índice de Gravidade de Doença , Medula Espinal/imunologia , Medula Espinal/patologia , alfa-Sinucleína/genéticaRESUMO
Climate change adaptation and mitigation strategies (CCAMS) are changes to the management of production forests motivated by the need to mitigate climate change, or adapt production forests to climate change risks. Sweden is employing CCAMS with unclear implications for biodiversity and forest ecosystem services (ES). Here, we synthesized evidence from 51 published scientific reviews, to evaluate the potential implications for biodiversity and a range of provisioning, regulating, and cultural ES, from the adoption of CCAMS relative to standard forestry practice. The CCAMS assessed were the adoption of (i) mixed-species stands, (ii) continuous cover forestry, (iii) altered rotation lengths, (iv) conversion to introduced tree species, (v) logging residue extraction, (vi) stand fertilization, and (vii) altered ditching/draining practices. We highlight the complexity of biodiversity and ES outcomes, identify knowledge gaps, and emphasize the importance of evidence-based decision making and landscape-scale planning when navigating choices involving the widespread adoption of CCAMS.
Assuntos
Mudança Climática , Ecossistema , Conservação dos Recursos Naturais , Florestas , Biodiversidade , Árvores , Europa (Continente) , Agricultura Florestal , Espécies IntroduzidasRESUMO
Biodiversity conservation and economic profit from forests can be combined by various land-sparing and land-sharing approaches. Using a semi-structured survey, we evaluated support for scenarios representing contrasting conservation strategies in a managed boreal forest landscape. Land-sparing approaches were supported by the conservation organisation, regional administrations and the forest company, mainly motivated by the benefit for biodiversity based on ecological theory. Land-sharing approaches were supported by one recreational organisation, some municipalities and the forest owners' association, mainly motivated by the delivery of ecosystem services. Stakeholder groups using certain ecosystem services had motivations that we related to an anthropocentric mindset, while others focused more on species conservation, which can be related both to an anthropocentric or an ecocentric mindsets. Forest conservation planning should consider stakeholders' preferences to handle land-use conflicts. Since reaching consensus among multiple stakeholders seems unfeasible, a combination of land-sparing and land-sharing approaches is probably the best compromise.
Assuntos
Ecossistema , Taiga , Conservação dos Recursos Naturais , Biodiversidade , FlorestasRESUMO
Inclusions of intraneuronal alpha-synuclein (α-synuclein) can be detected in brains of patients with Parkinson's disease and dementia with Lewy bodies. The aggregation of α-synuclein is a central feature of the disease pathogenesis. Among the different α-synuclein species, large oligomers/protofibrils have particular neurotoxic properties and should therefore be suitable as both therapeutic and diagnostic targets. Two monoclonal antibodies, mAb38F and mAb38E2, with high affinity and strong selectivity for large α-synuclein oligomers were generated. These antibodies, which do not bind amyloid-beta or tau, recognize Lewy body pathology in brains from patients with Parkinson's disease and dementia with Lewy bodies and detect pathology earlier in α-synuclein transgenic mice than linear epitope antibodies. An oligomer-selective sandwich ELISA, based on mAb38F, was set up to analyze brain extracts of the transgenic mice. The overall levels of α-synuclein oligomers/protofibrils were found to increase with age in these mice, although the levels displayed a large interindividual variation. Upon subcellular fractionation, higher levels of α-synuclein oligomers/protofibrils could be detected in the endoplasmic reticulum around the age when behavioral disturbances develop. In summary, our novel oligomer-selective α-synuclein antibodies recognize relevant pathology and should be important tools to further explore the pathogenic mechanisms in Lewy body disorders. Moreover, they could be potential candidates both for immunotherapy and as reagents in an assay to assess a potential disease biomarker.
Assuntos
Anticorpos Monoclonais/farmacologia , Encéfalo/patologia , Doença por Corpos de Lewy/genética , Doença por Corpos de Lewy/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/imunologia , Animais , Western Blotting , DNA Complementar/genética , Ensaio de Imunoadsorção Enzimática , Epitopos , Formiatos/química , Humanos , Imuno-Histoquímica , Camundongos , Camundongos Transgênicos , Mutação/genética , Mutação/fisiologia , Frações Subcelulares/metabolismoRESUMO
BACKGROUND: Alphaviral replicon-based vectors induce potent immune responses both when given as viral particles (VREP) or as DNA (DREP). It has been suggested that the strong immune stimulatory effect induced by these types of vectors is mediated by induction of danger signals and activation of innate signalling pathways due to the replicase activity. To investigate the innate signalling pathways involved, mice deficient in either toll-like receptors or downstream innate signalling molecules were immunized with DREP or VREP. RESULTS: We show that the induction of a CD8+ T cell response did not require functional TLR3 or MyD88 signalling. However, IRF3, converging several innate signalling pathways and important for generation of pro-inflammatory cytokines and type I IFNs, was needed for obtaining a robust primary immune response. Interestingly, type I interferon (IFN), induced by most innate signalling pathways, had a suppressing effect on both the primary and memory T cell responses after DREP and VREP immunization. CONCLUSIONS: We show that alphaviral replicon-based vectors activate multiple innate signalling pathways, which both activate and restrict the induced immune response. These results further show that there is a delicate balance in the strength of innate signalling and induction of adaptive immune responses that should be taken into consideration when innate signalling molecules, such as type I IFNs, are used as vaccine adjuvant.
Assuntos
Alphavirus/genética , Portadores de Fármacos , Vetores Genéticos , Imunidade Inata , Transdução de Sinais , Vacinas Virais/imunologia , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Camundongos , Camundongos KnockoutRESUMO
BACKGROUND: Multiple myeloma is an incurable haematological malignancy, representing over 10% of haematological cancers in the USA. We did a phase 1-2 study of melflufen and dexamethasone in patients with relapsed and refractory multiple myeloma to determine the maximum tolerated dose of melflufen and to investigate its safety and efficacy. METHODS: We did a multicentre, international, dose-confirmation and dose-expansion, open-label, phase 1-2 study in seven centres in the USA and Europe. Eligible patients were aged 18 years or older, had relapsed and refractory multiple myeloma, had received two or more previous lines of therapy (including lenalidomide and bortezomib), were refractory to their last line of therapy, and had an Eastern Cooperative Oncology Group performance status of 2 or less. In phase 1, patients received an intravenous infusion of melflufen at 15 mg, 25 mg, 40 mg, or 55 mg for 30 min on day 1 in 21-day cycles plus oral dexamethasone 40 mg weekly and did not receive melflufen as a single agent. Melflufen was also tested in a single-agent cohort late in phase 2 in a small number of patients at the maximum tolerated dose identified in phase 1. In phase 2, patients were enrolled at the maximum tolerated dose in the melflufen plus dexamethasone in the combination cohort.. The phase 1 primary objective was to determine the maximum tolerated dose. The phase 2 primary objective was to evaluate overall response rate and clinical benefit rate. This primary analysis was done per protocol, in the all-treated and efficacy-evaluable population (defined as patients who received at least two doses of melflufen and who had a response assessment after baseline). The single-agent melflufen cohort was closed on October 6, 2016, as per the recommendation by the data safety monitoring committee on the basis of interim data suggesting greater activity in the melflufen plus dexamethasone cohort. The study is completed but survival follow-up is ongoing. This study is registered with ClinicalTrials.gov, NCT01897714. FINDINGS: Patients were enrolled between July 4, 2013, and Dec 31, 2016: 23 patients in phase 1 and 58 in phase 2, including six patients from phase 1 treated at the maximum tolerated dose of melflufen 40 mg plus weekly dexamethasone. In phase 2, 45 patients were given a combination of melflufen plus dexamethasone and 13 patients were given single-agent melflufen. In phase 1, the established maximum tolerated dose was 40 mg of melflufen in combination with dexamethasone. No dose-limiting toxicities were observed in the first three dose cohorts (15 mg, 25 mg, and 40 mg). The highest dose cohort tested (55 mg) exceeded the maximum tolerated dose because four of six patients experienced grade 4 neutropenia with grade 4 thrombocytopenia also occurring in three of these patients; therefore, the planned highest dose of 70 mg was not tested. In phase 2, patients treated with combination therapy achieved an overall response rate of 31% (14 of 45 patients; 95% CI 18-47) and clinical benefit rate of 49% (22 of 45; 34-64) in the all-treated population, and 41% (14 of 34; 25-59) and 65% (22 of 34; 47-80) in the efficacy-evaluable population. In the phase 2 single-agent cohort, the overall response rate was 8% (one of 13 patients; 0·2-36·0) and the clinical benefit rate was 23% (three of 13; 5-54). Among the 45 patients given melflufen plus dexamethasone during phase 2, the most common grade 3-4 adverse events were clinically manageable thrombocytopenia (28 [62%] patients) and neutropenia (26 [58%]), and non-haematological toxicity was infrequent. 24 serious adverse events were reported in 17 (38%) of 45 patients, most commonly pneumonia (five [11%]). The most common grade 3-4 adverse events that occurred in the phase 2 single-agent cohort of 13 patients were neutropenia (nine [69%]) and thrombocytopenia (eight [62%]). Nine patients experienced serious adverse events in the single-agent cohort, most commonly thrombocytopenia (two [15%]). There were three deaths from adverse events within 30 days of treatment that were possibly related to treatment: one in the 25 mg cohort in phase 1 (due to bacteraemia) and two in the phase 2 combination cohort (one due to neutropenic sepsis and one due to Escherichia coli sepsis), each in the setting of progressive disease. INTERPRETATION: These data show that melflufen is active in patients with relapsed and refractory multiple myeloma and tolerable in most patients. These results show the feasibility of this regimen and support the initiation of additional clinical studies of melflufen in multiple myeloma, both in combination with dexamethasone as well as in triplet regimens with additional classes of drugs. FUNDING: Oncopeptides AB.
Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Antineoplásicos Hormonais/uso terapêutico , Dexametasona/uso terapêutico , Melfalan/análogos & derivados , Mieloma Múltiplo/tratamento farmacológico , Fenilalanina/análogos & derivados , Idoso , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Dexametasona/administração & dosagem , Dexametasona/efeitos adversos , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Dose Máxima Tolerável , Melfalan/administração & dosagem , Melfalan/efeitos adversos , Melfalan/uso terapêutico , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Fenilalanina/administração & dosagem , Fenilalanina/efeitos adversos , Fenilalanina/uso terapêuticoRESUMO
BACKGROUND: Poor mental health has large social and economic consequences both for the individual and society. In Sweden, the prevalence of mental health symptoms has increased since the beginning of the 1990 s. There is a need for a better understanding of the area for planning preventive activities and health care. METHODS: The study is based on a postal survey questionnaire sent to a random sample of men and women aged 18-84 years in 2004. The overall response rate was 64%. The area investigated covers 55 municipalities with about one million inhabitants in central part of Sweden. The study population includes 42,448 respondents. Mental health was measured with self-reported symptoms of anxiety/depression (EQ-5D, 5th question). The association between socio-economic conditions, lifestyle factors and mental health symptoms was investigated using multivariate multinomial logistic regression models. RESULTS: About 40% of women and 30% of men reported that they were moderately or extremely anxious or depressed. Younger subjects reported poorer mental health than older subjects, the best mental health was found at ages 65-74 years. Factors that were strongly and independently related to mental health symptoms were poor social support, experiences of being belittled, employment status (receiving a disability pension and unemployment), economic hardship, critical life events, and functional disability. A strong association was also found between how burdensome domestic work was experienced and anxiety/depression. This was true for both men and women. Educational level was not associated with mental health symptoms. Of lifestyle factors, physical inactivity, underweight and risk consumption of alcohol were independently associated with mental health symptoms. CONCLUSION: Our results support the notion that a ground for good mental health includes balance in social relations, in domestic work and in employment as well as in personal economy both among men and women. In addition, physical inactivity, underweight and risk consumption of alcohol are associated with mental health symptoms independent of socio-economic factors.
Assuntos
Saúde Mental , Fatores Socioeconômicos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estilo de Vida , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Suécia/epidemiologiaRESUMO
Synucleinopathies represent a group of neurodegenerative disorders which are characterized by intracellular accumulation of aggregated α-synuclein. α-synuclein misfolding and oligomer formation is considered a major pathogenic trigger in these disorders. Therefore, targeting α-synuclein species represents an important candidate therapeutic approach. Our aim was to analyze the biological effects of passive immunization targeting α-synuclein and to identify the possible underlying mechanisms in a transgenic mouse model of oligodendroglial α-synucleinopathy. We used PLP-α-synuclein mice overexpressing human α-synuclein in oligodendrocytes. The animals received either antibodies that recognize α-synuclein or vehicle. Passive immunization mitigated α-synuclein pathology and resulted in reduction of total α-synuclein in the hippocampus, reduction of intracellular accumulation of aggregated α-synuclein, particularly significant in the spinal cord. Lowering of the extracellular oligomeric α-synuclein was associated with reduction of the density of activated iba1-positive microglia profiles. However, a shift toward phagocytic microglia was seen after passive immunization of PLP-α-synuclein mice. Lowering of intracellular α-synuclein was mediated by autophagy degradation triggered after passive immunization in PLP-α-synuclein mice. In summary, the study provides evidence for the biological efficacy of immunotherapy in a transgenic mouse model of oligodendroglial synucleinopathy. The different availability of the therapeutic antibodies and the variable load of α-synuclein pathology in selected brain regions resulted in differential effects of the immunotherapy that allowed us to propose a model of the underlying mechanisms of antibody-aided α-synuclein clearance.
RESUMO
Introduction: Intraneuronal inclusions of alpha-synuclein are commonly found in the brain of patients with Parkinson's disease and other α-synucleinopathies. The correlation between alpha-synuclein pathology and symptoms has been studied in various animal models. In (Thy-1)-h[A30P] alpha-synuclein transgenic mice, behavioral and motor abnormalities were reported from 12 and 15 months, respectively. The aim of this study was to investigate whether these mice also display symptoms at earlier time points. Methods: We analyzed gait deficits, locomotion, and behavioral profiles in (Thy-1)-h[A30P] alpha-synuclein and control mice at 2, 8, and 11 months of age. In addition, inflammatory markers, levels of alpha-synuclein oligomers, and tyrosine hydroxylase reactivity were studied. Results: Already at 2 months of age, transgenic mice displayed fine motor impairments in the challenging beam test that progressively increased up to 11 months of age. At 8 months, transgenic mice showed a decreased general activity with increased risk-taking behavior in the multivariate concentric square field test. Neuropathological analyses of 8- and 11-month-old mice revealed accumulation of oligomeric alpha-synuclein in neuronal cell bodies. In addition, a decreased presence of tyrosine hydroxylase suggests a dysregulation of the dopaminergic system in the transgenic mice, which in turn may explain some of the motor impairments observed in this mouse model. Conclusions: Taken together, our results show that the (Thy-1)-h[A30P] alpha-synuclein transgenic mouse model displays early Parkinson's disease-related symptoms with a concomitant downregulation of the dopaminergic system. Thus, this should be an appropriate model to study early phenotypes of alpha-synucleinopathies.
Assuntos
Comportamento Animal/fisiologia , Transtornos Motores/fisiopatologia , Transtornos Motores/psicologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/psicologia , Animais , Modelos Animais de Doenças , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Atividade Motora , alfa-SinucleínaRESUMO
This study examines which kinds of social benefits derived from forests are emphasised by Swedish stakeholders and what governance modes and management tools they accept. Our study shows that there exists a great variety among stakeholders' perceptions of forests' social values, where tourism and recreation is the most common reference. There are also differences in preferred governance modes and management where biomass and bioenergy sectors advocate business as usual (i.e. framework regulations and voluntarism) and other stakeholders demand rigid tools (i.e. coercion and targeting) and improved landscape planning. This divide will have implications for future policy orientations and require deliberative policy processes and improved dialogue among stakeholders and authorities. We suggest that there is a potential for these improvements, since actors from almost all stakeholder groups support local influence on governance and management, acknowledged and maintained either by the authorities, i.e. targeting, or by the stakeholders themselves, i.e. voluntarism.
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Agricultura Florestal/métodos , Florestas , Valores Sociais , Política Ambiental , Propriedade , Opinião Pública , Percepção Social , SuéciaRESUMO
Conflicting perspectives on forests has for a long time challenged forest policy development in Sweden. Disagreements about forest futures create intractable deadlocks when stakeholders talk past each other. The purpose of this study is to move beyond this situation through the application of participatory backcasting. By comparing visions of the future forest among stakeholder groups, we highlight contemporary trajectories and identify changes that were conceived as desirable. We worked with four groups: the Biomass and Bioenergy group, the Conservation group, the Sami Livelihood group and the Recreation and Rural Development group; in total representatives from 40 organizations participated in workshops articulating the groups' visions. Our results show well-known tensions such as intrinsic versus instrumental values but also new ones concerning forests' social values. Identified synergies include prioritization of rural development, new valued-added forest products and diversified forest management. The results may feed directly into forest policy processes facilitating the process and break current deadlocks.
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Agricultura Florestal/tendências , Conservação dos Recursos Naturais/tendências , Política Ambiental , Propriedade , Recreação , SuéciaRESUMO
Immunotherapy targeting α-synuclein has evolved as a potential therapeutic strategy for neurodegenerative diseases, such as Parkinson's disease, and initial studies on cellular and animal models have shown promising results. α-synuclein vaccination of transgenic mice reduced the number of brain inclusions, whereas passive immunization studies demonstrated that antibodies against the C-terminus of α-synuclein can pass the blood-brain barrier and affect the pathology. In addition, preliminary evidence suggests that transgenic mice treated with an antibody directed against α-synuclein oligomers/protofibrils resulted in reduced levels of such species in the CNS. The underlying mechanisms of immunotherapy are not yet fully understood, but may include antibody-mediated clearance of pre-existing aggregates, prevention of protein propagation between cells and microglia-dependent protein clearance. Thus, immunotherapy targeting α-synuclein holds promise, but needs to be further developed as a future disease-modifying treatment in Parkinson's disease and other α-synucleinopathies.
Assuntos
Imunoterapia , Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/terapia , Doença de Parkinson/terapia , alfa-Sinucleína/imunologia , Animais , Anticorpos Monoclonais/metabolismo , Humanos , Imunoterapia/tendências , Doença por Corpos de Lewy/imunologia , Camundongos , Camundongos Transgênicos , Terapia de Alvo Molecular , Doença de Parkinson/imunologia , Resposta a Proteínas não Dobradas/imunologia , alfa-Sinucleína/genéticaRESUMO
Ligands of pattern recognition receptors (PRRs) including Toll-like receptors (TLRs) stimulate innate and adaptive immune responses and are considered as potent adjuvants. Combinations of ligands might act in synergy to induce stronger and broader immune responses compared to stand-alone ligands. Alphaviruses stimulate endosomal TLRs 3, 7 and 8 as well as the cytoplasmic PRR MDA-5, resulting in induction of a strong type I interferon (IFN) response. Bacterial flagellin stimulates TLR5 and when delivered intracellularly the cytosolic PRR NLRC4, leading to secretion of proinflammatory cytokines. Both alphaviruses and flagellin have independently been shown to act as adjuvants for antigen-specific antibody responses. Here, we hypothesized that alphavirus and flagellin would act in synergy when combined. We therefore cloned the Salmonella Typhimurium flagellin (FliC) gene into an alphavirus replicon and assessed its adjuvant activity on the antibody response against co-administered antigen. In mice immunized with recombinant alphavirus, antibody responses were greatly enhanced compared to soluble FliC or control alphavirus. Both IgG1 and IgG2a/c responses were increased, indicating an enhancement of both Th1 and Th2 type responses. The adjuvant activity of FliC-expressing alphavirus was diminished but not abolished in the absence of TLR5 or type I IFN signaling, suggesting the contribution of several signaling pathways and some synergistic and redundant activity of its components. Thus, we have created a recombinant adjuvant that stimulates multiple signaling pathways of innate immunity resulting in a strong and broad antibody response.
Assuntos
Alphavirus/genética , Alphavirus/imunologia , Flagelina/genética , Flagelina/imunologia , Replicon , Adjuvantes Imunológicos , Alphavirus/metabolismo , Animais , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Linhagem Celular , Cricetinae , Expressão Gênica , Imunoglobulina G/imunologia , Interferon Tipo I/metabolismo , Camundongos , Camundongos Knockout , Salmonella typhimurium/genética , Salmonella typhimurium/imunologia , Transdução de Sinais , Receptor 5 Toll-Like/genética , Receptor 5 Toll-Like/metabolismoRESUMO
Recent research implicates soluble aggregated forms of α-synuclein as neurotoxic species with a central role in the pathogenesis of Parkinson's disease and related disorders. The pathway by which α-synuclein aggregates is believed to follow a step-wise pattern, in which dimers and smaller oligomers are initially formed. Here, we used H4 neuroglioma cells expressing α-synuclein fused to hemi:GFP constructs to study the effects of α-synuclein monoclonal antibodies on the early stages of aggregation, as quantified by Bimolecular Fluorescence Complementation assay. Widefield and confocal microscopy revealed that cells treated for 48 h with monoclonal antibodies internalized antibodies to various degrees. C-terminal and oligomer-selective α-synuclein antibodies reduced the extent of α-synuclein dimerization/oligomerization, as indicated by decreased GFP fluorescence signal. Furthermore, ELISA measurements on lysates and conditioned media from antibody treated cells displayed lower α-synuclein levels compared to untreated cells, suggesting increased protein turnover. Taken together, our results propose that extracellular administration of monoclonal antibodies can modify or inhibit early steps in the aggregation process of α-synuclein, thus providing further support for passive immunization against diseases with α-synuclein pathology.