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1.
Cells ; 13(11)2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38891073

RESUMO

Regulatory T cells (Tregs) are essential to maintain immune homeostasis by promoting self-tolerance. Reduced Treg numbers or functionality can lead to a loss of tolerance, increasing the risk of developing autoimmune diseases. An overwhelming variety of human Tregs has been described, based on either specific phenotype, tissue compartment, or pathological condition, yet the bulk of the literature only addresses CD25-positive and CD127-negative cells, coined by naturally occurring Tregs (nTregs), most of which express the transcription factor Forkhead box protein 3 (FOXP3). While the discovery of FOXP3 was seminal to understanding the origin and biology of nTregs, there is evidence in humans that not all T cells expressing FOXP3 are regulatory, and that not all Tregs express FOXP3. Namely, the activation of human T cells induces the transient expression of FOXP3, irrespective of whether they are regulatory or inflammatory effectors, while some induced T cells that may be broadly defined as Tregs (e.g., Tr1 cells) typically lack demethylation and do not express FOXP3. Furthermore, it is unknown whether and how many nTregs exist without FOXP3 expression. Several other candidate regulatory molecules, such as GITR, Lag-3, GARP, GPA33, Helios, and Neuropilin, have been identified but subsequently discarded as Treg-specific markers. Multiparametric analyses have uncovered a plethora of Treg phenotypes, and neither single markers nor combinations thereof can define all and only Tregs. To date, only the functional capacity to inhibit immune responses defines a Treg and distinguishes Tregs from inflammatory T cells (Teffs) in humans. This review revisits current knowledge of the Treg universe with respect to their heterogeneity in phenotype and function. We propose that it is unavoidable to characterize human Tregs by their phenotype in combination with their function, since phenotype alone does not unambiguously define Tregs. There is an unmet need to align the expression of specific markers or combinations thereof with a particular suppressive function to coin functional Treg entities and categorize Treg diversity.


Assuntos
Fatores de Transcrição Forkhead , Fenótipo , Linfócitos T Reguladores , Humanos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Fatores de Transcrição Forkhead/metabolismo
2.
Public Health Pract (Oxf) ; 7: 100498, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38779506

RESUMO

Background: Enabling, supporting and promoting positive health-related behaviours is critical in addressing the major public health challenges of our time, and the multifaceted nature of behaviours requires an evidence-based approach. This statement seeks to suggest how a much-needed enhanced use of behavioural and cultural science and insights for health could be advanced. Study design and methods: and methods: Public health authorities of Europe and Central Asia and international partner organizations in September 2023 met in Copenhagen, Denmark, to discuss the way forward. Drawing on 1) country reporting to WHO, 2) interview study with public health authorities and 3) the meeting deliberations, this meeting statement was developed. Results: The meeting statement presents a joint call for step-change accelerated use of evidence-based approaches for health behaviours. Actionable next steps for public health authorities and international and regional development partners in health are presented. Conclusions: The way forward involves increased resource allocation, integration of behavioural insights into health strategies, advocacy through case and cost-effectiveness examples and capacity building.

3.
Diagnostics (Basel) ; 14(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38472981

RESUMO

Although previous studies indicated that chronic alcohol abuse (CAA) and alcoholic liver cirrhosis (ALC) are associated with increased bone fragility, understanding bone fragility determinants is still modest in these individuals. We used a comprehensive individualized clinical fracture risk assessment approach (vertebral osteodensitometry, femoral osteodensitometry and geometry, and serum bone turnover biomarkers) to compare adult male patients with ALC who have not previously had femoral or vertebral fractures (n = 39), patients with CAA (without liver cirrhosis, n = 78) who have not previously had femoral or vertebral fractures and healthy age- and sex-matched controls (n = 43). Our data suggested that intertrochanteric bone mineral density was significantly lower in ALC and CAA patients than in controls. Also, the trabecular bone score was considerably lower in ALC patients compared with CAA and control individuals. The most significant inter-group differences in femoral geometry were noted on the femoral shaft. Patients with ALC and CAA have a higher 10-year risk of major osteoporotic fractures compared to the controls. Analysis of bone turnover biomarkers showed increased osteoprotegerin and beta-C-terminal telopeptide serum concentrations and decreased insulin growth factor-1 concentrations in patients with ALC compared to CAA and control groups. Our data revealed that bone alterations are present in patients with ALC and CAA even if they did not sustain a nontraumatic bone fracture, but it is also indicative that current bone-assessing clinical methods are not entirely reliable. Thus, future studies should focus on developing a reliable integrative clinical tool that can be used to accurately predict and prevent bone fracture occurrences in patients with ALC and CAA.

4.
Cells ; 12(24)2023 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-38132134

RESUMO

Tryptophan (TRP) catabolites exert neuroactive effects, with the plethora of evidence suggesting that kynurenic acid (KYNA), a catabolite of the kynurenine pathway (KP), acts as the regulator of glutamate and acetylcholine in the brain, contributing to the schizophrenia pathophysiology. Newer evidence regarding measures of KP metabolites in the blood of schizophrenia patients and from the central nervous system suggest that blood levels of these metabolites by no means could reflect pathological changes of TRP degradation in the brain. The aim of this study was to investigate plasma concentrations of TRP, kynurenine (KYN) and KYNA at the acute phase and remission of schizophrenia in a prospective, case-control study of highly selected and matched schizophrenia patients and healthy individuals. Our study revealed significantly decreased KYN and KYNA in schizophrenia patients (p < 0.001), irrespective of illness state, type of antipsychotic treatment, number of episodes or illness duration and no differences in the KYN/TRP ratio between schizophrenia patients and healthy individuals. These findings could be interpreted as indices that kynurenine pathway might not be dysregulated in the periphery and that other factors contribute to observed disturbances in concentrations, but as our study had certain limitations, we cannot draw definite conclusions. Further studies, especially those exploring other body compartments that participate in kynurenine pathway, are needed.


Assuntos
Antipsicóticos , Esquizofrenia , Humanos , Cinurenina/metabolismo , Ácido Cinurênico/metabolismo , Antipsicóticos/uso terapêutico , Esquizofrenia/tratamento farmacológico , Estudos de Casos e Controles , Estudos Prospectivos , Triptofano/metabolismo
5.
Front Immunol ; 13: 1054968, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505460

RESUMO

Introduction: Restoration of immune tolerance may halt progression of autoimmune diseases. Tolerogenic dendritic cells (tolDC) inhibit antigen-specific proinflammatory T-cells, generate antigen-specific regulatory T-cells and promote IL-10 production in-vitro, providing an appealing immunotherapy to intervene in autoimmune disease progression. Methods: A placebo-controlled, dose escalation phase 1 clinical trial in nine adult patients with long-standing type 1 diabetes (T1D) demonstrated the safety and feasibility of two (prime-boost) vaccinations with tolDC pulsed with a proinsulin peptide. Immunoregulatory effects were monitored by antigen-specific T-cell assays and flow and mass cytometry. Results: The tolDC vaccine induced a profound and durable decline in pre-existing autoimmune responses to the vaccine peptide up to 3 years after therapy and temporary decline in CD4 and CD8+ T-cell responses to other islet autoantigens. While major leukocyte subsets remained stable, ICOS+CCR4+TIGIT+ Tregs and CD103+ tissue-resident and CCR6+ effector memory CD4+ T-cells increased in response to the first tolDC injection, the latter declining thereafter below baseline levels. Discussion: Our data identify immune correlates of mechanistic efficacy of intradermally injected tolDC reducing proinsulin autoimmunity in T1D.


Assuntos
Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Adulto , Humanos , Células Dendríticas , Diabetes Mellitus Tipo 1/terapia , Tolerância Imunológica , Proinsulina
6.
Front Immunol ; 13: 886736, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35603161

RESUMO

Type 1 diabetes (T1D) is an autoimmune disease that develops in the interplay between genetic and environmental factors. A majority of individuals who develop T1D have a HLA make up, that accounts for 50% of the genetic risk of disease. Besides these HLA haplotypes and the insulin region that importantly contribute to the heritable component, genome-wide association studies have identified many polymorphisms in over 60 non-HLA gene regions that also contribute to T1D susceptibility. Combining the risk genes in a score (T1D-GRS), significantly improved the prediction of disease progression in autoantibody positive individuals. Many of these minor-risk SNPs are associated with immune genes but how they influence the gene and protein expression and whether they cause functional changes on a cellular level remains a subject of investigation. A positive correlation between the genetic risk and the intensity of the peripheral autoimmune response was demonstrated both for HLA and non-HLA genetic risk variants. We also observed epigenetic and genetic modulation of several of these T1D susceptibility genes in dendritic cells (DCs) treated with vitamin D3 and dexamethasone to acquire tolerogenic properties as compared to immune activating DCs (mDC) illustrating the interaction between genes and environment that collectively determines risk for T1D. A notion that targeting such genes for therapeutic modulation could be compatible with correction of the impaired immune response, inspired us to review the current knowledge on the immune-related minor risk genes, their expression and function in immune cells, and how they may contribute to activation of autoreactive T cells, Treg function or ß-cell apoptosis, thus contributing to development of the autoimmune disease.


Assuntos
Doenças Autoimunes , Diabetes Mellitus Tipo 1 , Autoimunidade/genética , Diabetes Mellitus Tipo 1/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Polimorfismo de Nucleotídeo Único
7.
Drug Metab Pers Ther ; 37(3): 271-275, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35254746

RESUMO

OBJECTIVES: The newborn screening (NBS) program in the Republic of Serbia has several decades of tradition, but it has not included any organic acidemias (OA). Therefore, this study aimed to establish the cut-offs of the corresponding NBS markers in the population of healthy newborns. METHODS: In dried blood samples (DBS) collected from 1,771 healthy newborns, we analyzed levels of propionylcarnitine (C3), isovalerylcarnitine (C5), and glutarylcarnitine (C5DC) using tandem mass spectrometry. Further we calculated the following ratios: C3/acetylcarnitine (C3/C2), C3/palmitoylcarnitine (C3/C16), C5/ free carnitine (C0), C5/C2, C5/C3, C5DC/octanoylcarnitine (C8), and C5DC/C0. RESULTS: The cut-offs for methylmalonic acidemia (MMA) or propionic acidemia (PA) were C3>5.73 µmol/L, C3/C2>0.23, and C3/C16>2.36. Based on the study findings, the screening results indicative for isovaleric acidemia (IVA) would include C5>0.372 µmol/L, C5/C0>0.020, C5/C2>0.019, and C5/C3>0.31. Finally, C5DC>0.303 µmol/L, C5DC/C8>7.1, and C5DC/C0>0.019 would justify further testing for glutaric acidemia type I (GA1). The cut-offs were satisfactorily validated via the comparison with worldwide estimates and data for several Caucasian populations. CONCLUSIONS: The levels of the OA biomarkers in the Serbian population of healthy newborns have a distribution pattern similar to the other world populations. Therefore, the proposed cut-offs represent a reliable starting point for the future development of the OA NBS.


Assuntos
Acidemia Propiônica , Erros Inatos do Metabolismo dos Aminoácidos , Biomarcadores , Encefalopatias Metabólicas , Glutaril-CoA Desidrogenase/deficiência , Humanos , Recém-Nascido , Isovaleril-CoA Desidrogenase , Acidemia Propiônica/diagnóstico , Sérvia
8.
Eur J Immunol ; 51(6): 1377-1389, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33728639

RESUMO

The Ig superfamily protein glycoprotein A33 (GPA33) has been implicated in immune dysregulation, but little is known about its expression in the immune compartment. Here, we comprehensively determined GPA33 expression patterns on human blood leukocyte subsets, using mass and flow cytometry. We found that GPA33 was expressed on fractions of B, dendritic, natural killer and innate lymphoid cells. Most prominent expression was found in the CD4+ T cell compartment. Naïve and CXCR5+ regulatory T cells were GPA33high , and naïve conventional CD4+ T cells expressed intermediate GPA33 levels. The expression pattern of GPA33 identified functional heterogeneity within the CD4+ central memory T cell (Tcm) population. GPA33+ CD4+ Tcm cells were fully undifferentiated, bona fide Tcm cells that lack immediate effector function, whereas GPA33- Tcm cells exhibited rapid effector functions and may represent an early stage of differentiation into effector/effector memory T cells before loss of CD62L. Expression of GPA33 in conventional CD4+ T cells suggests a role in localization and/or preservation of an undifferentiated state. These results form a basis to study the function of GPA33 and show it to be a useful marker to discriminate between different cellular subsets, especially in the CD4+ T cell lineage.


Assuntos
Biomarcadores/metabolismo , Linfócitos T CD4-Positivos/imunologia , Leucócitos Mononucleares/imunologia , Glicoproteínas de Membrana/metabolismo , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Diferenciação Celular , Linhagem da Célula , Separação Celular , Citometria de Fluxo , Células HEK293 , Humanos , Imunidade Inata , Memória Imunológica , Glicoproteínas de Membrana/genética , Receptores CXCR5/metabolismo
9.
Artigo em Inglês | MEDLINE | ID: mdl-33451090

RESUMO

In view of ongoing demographic developments resulting in a longer life expectancy of the European population, the creation of "age-friendly" environments represents an initiative picked up by the European Union and its Member States to enable active and healthy ageing. The present study aims at the co-creation of a cross-border framework model to deploy a healthy ageing region linking Austria and Slovenia, building on previous work dealing with the development of an integrated regional ecosystem for active and healthy ageing. A qualitative, community-based action research method based on focus group discussions allowed the development of an exemplary framework model for active and healthy ageing building on cross-border collaboration in the region of Promura. Within the project group, twelve cross-border regional key assets were identified. In the course of further open discussions, an exemplary model for the deployment of a cross-border healthy ageing region was developed, comprising underlying fundamental environmental aspects, regional structures in the field of health and care as well as crosscutting features spreading across all levels. This article presents a promising, strategic co-creation approach on how to span a model on active and healthy ageing across two cross-border regions with similar characteristics and assets.


Assuntos
Envelhecimento Saudável , Áustria , Ecossistema , União Europeia , Eslovênia
10.
Cytotherapy ; 23(3): 242-255, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33461863

RESUMO

Autologous, antigen-specific, tolerogenic dendritic cells (tolDCs) are presently assessed to reverse and possibly cure autoimmune diseases such as type 1 diabetes (T1D). Good Manufacturing Practice production and clinical implementation of such cell therapies critically depend on their stability and reproducible production from healthy donors and, more importantly, patient-derived monocytes. Here the authors demonstrate that tolDCs (modulated using 1,25-dihydroxyvitamin D3 and dexamethasone) displayed similar features, including protein, transcriptome and epigenome profiles, between two international clinical centers and between T1D and healthy donors, validating reproducible production. In addition, neither phenotype nor function of tolDCs was affected by repeated stimulation with inflammatory stimuli, underscoring their stability as semi-mature DCs. Furthermore, tolDCs exhibited differential DNA methylation profiles compared with inflammatory mature DCs (mDCs), and this was already largely established prior to maturation, indicating that tolDCs are locked into an immature state. Finally, approximately 80% of differentially expressed known T1D risk genes displayed a corresponding differential DNA methylome in tolDCs versus mDCs and metabolic and immune pathway genes were also differentially methylated and expressed. In summary, tolDCs are reproducible and stable clinical cell products unaffected by the T1D status of donors. The observed stable, semi-mature phenotype and function of tolDCs are exemplified by epigenetic modifications representative of immature-stage cells. Together, the authors' data provide a strong basis for the production and clinical implementation of tolDCs in the treatment of autoimmune diseases such as T1D.


Assuntos
Calcitriol , Diabetes Mellitus Tipo 1 , Calcitriol/farmacologia , Células Dendríticas , Epigênese Genética , Humanos , Tolerância Imunológica
13.
Cytotherapy ; 22(7): 388-397, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32414635

RESUMO

BACKGROUND AIMS: Recent technical and clinical advances with cell-based therapies (CBTs) hold great promise in the treatment of patients with rare diseases and those with high unmet medical need. Currently the majority of CBTs are developed and manufactured in specialized academic facilities. Due to small scale, unique characteristics and specific supply chain, CBT manufacturing is considered costly compared to more conventional medicinal products. As a result, biomedical researchers and clinicians are increasingly faced with cost considerations in CBT development. The objective of this research was to develop a costing framework and methodology for academic and other small-scale facilities that manufacture cell-based therapies. METHODS: We conducted an international multi-center costing study in four facilities in Europe using eight CBTs as case studies. This study includes costs from cell or tissue procurement to release of final product for clinical use. First, via interviews with research scientists, clinicians, biomedical scientists, pharmacists and technicians, we designed a high-level costing framework. Next, we developed a more detailed uniform methodology to allocate cost items. Costs were divided into steps (tissue procurement, manufacturing and fill-finish). The steps were each subdivided into cost categories (materials, equipment, personnel and facility), and each category was broken down into facility running (fixed) costs and operational (variable) costs. The methodology was tested via the case studies and validated in developer interviews. Costs are expressed in 2018 euros (€). RESULTS: The framework and methodology were applicable across facilities and proved sensitive to differences in product and facility characteristics. Case study cost estimates ranged between €23 033 and €190 799 Euros per batch, with batch yield varying between 1 and 88 doses. The cost estimations revealed hidden costs to developers and provided insights into cost drivers to help design manufacturing best practices. CONCLUSIONS: This framework and methodology provide step-by-step guidance to estimate manufacturing costs specifically for cell-based therapies manufactured in academic and other small-scale enterprises. The framework and methodology can be used to inform and plan cost-conscious strategies for CBTs.


Assuntos
Academias e Institutos , Terapia Baseada em Transplante de Células e Tecidos/economia , Custos e Análise de Custo , Comércio , Europa (Continente) , Instalações de Saúde , Humanos
14.
Diabetologia ; 63(3): 597-610, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31915895

RESUMO

AIMS/HYPOTHESIS: The pathophysiology of type 1 diabetes has been linked to altered gut microbiota and more specifically to a shortage of intestinal production of the short-chain fatty acid (SCFA) butyrate, which may play key roles in maintaining intestinal epithelial integrity and in human and gut microbial metabolism. Butyrate supplementation can protect against autoimmune diabetes in mouse models. We thus set out to study the effect of oral butyrate vs placebo on glucose regulation and immune variables in human participants with longstanding type 1 diabetes. METHODS: We administered a daily oral dose of 4 g sodium butyrate or placebo for 1 month to 30 individuals with longstanding type 1 diabetes, without comorbidity or medication use, in a randomised (1:1), controlled, double-blind crossover trial, with a washout period of 1 month in between. Participants were randomly allocated to the 'oral sodium butyrate capsules first' or 'oral placebo capsules first' study arm in blocks of five. The clinical investigator received blinded medication from the clinical trial pharmacy. All participants, people doing measurements or examinations, or people assessing the outcomes were blinded to group assignment. The primary outcome was a change in the innate immune phenotype (monocyte subsets and in vitro cytokine production). Secondary outcomes were changes in blood markers of islet autoimmunity (cell counts, lymphocyte stimulation indices and CD8 quantum dot assays), glucose and lipid metabolism, beta cell function (by mixed-meal test), gut microbiota and faecal SCFA. The data was collected at the Amsterdam University Medical Centers. RESULTS: All 30 participants were analysed. Faecal butyrate and propionate levels were significantly affected by oral butyrate supplementation and butyrate treatment was safe. However, this modulation of intestinal SCFAs did not result in any significant changes in adaptive or innate immunity, or in any of the other outcome variables. In our discussion, we elaborate on this important discrepancy with previous animal work. CONCLUSIONS/INTERPRETATION: Oral butyrate supplementation does not significantly affect innate or adaptive immunity in humans with longstanding type 1 diabetes. TRIAL REGISTRATION: Netherlands Trial Register: NL4832 (www.trialregister.nl). DATA AVAILABILITY: Raw sequencing data are available in the European Nucleotide Archive repository (https://www.ebi.ac.uk/ena/browse) under study PRJEB30292. FUNDING: The study was funded by a Le Ducq consortium grant, a CVON grant, a personal ZONMW-VIDI grant and a Dutch Heart Foundation grant.


Assuntos
Autoimunidade/efeitos dos fármacos , Ácido Butírico/administração & dosagem , Diabetes Mellitus Tipo 1/tratamento farmacológico , Imunidade Inata/efeitos dos fármacos , Ilhotas Pancreáticas/imunologia , Imunidade Adaptativa/efeitos dos fármacos , Administração Oral , Adulto , Ácido Butírico/efeitos adversos , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/patologia , Progressão da Doença , Feminino , Humanos , Ilhotas Pancreáticas/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Países Baixos , Fatores de Tempo , Adulto Jovem
15.
J Autoimmun ; 107: 102361, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31776056

RESUMO

Induction of antigen-specific regulatory T cells (Tregs) in vivo is the holy grail of current immune-regulating therapies in autoimmune diseases, such as type 1 diabetes. Tolerogenic dendritic cells (tolDCs) generated from monocytes by a combined treatment with vitamin D and dexamethasone (marked by CD52hi and CD86lo expression) induce antigen-specific Tregs. We evaluated the phenotypes of these Tregs using high-dimensional mass cytometry to identify a surface-based T cell signature of tolerogenic modulation. Naïve CD4+ T cells were stimulated with tolDCs or mature inflammatory DCs pulsed with proinsulin peptide, after which the suppressive capacity, cytokine production and phenotype of stimulated T cells were analysed. TolDCs induced suppressive T cell lines that were dominated by a naïve phenotype (CD45RA+CCR7+). These naïve T cells, however, did not show suppressive capacity, but were arrested in their naïve status. T cell cultures stimulated by tolDC further contained memory-like (CD45RA-CCR7-) T cells expressing regulatory markers Lag-3, CD161 and ICOS. T cells expressing CD25lo or CD25hi were most prominent and suppressed CD4+ proliferation, while CD25hi Tregs also effectively supressed effector CD8+ T cells. We conclude that tolDCs induce antigen-specific Tregs with various phenotypes. This extends our earlier findings pointing to a functionally diverse pool of antigen-induced and specific Tregs and provides the basis for immune-monitoring in clinical trials with tolDC.


Assuntos
Autoimunidade , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Tolerância Imunológica , Peptídeos/imunologia , Proinsulina/imunologia , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/metabolismo , Animais , Biomarcadores , Citocinas/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Diabetes Mellitus Tipo 1/metabolismo , Humanos , Imunofenotipagem , Monócitos/imunologia , Monócitos/metabolismo
16.
Front Immunol ; 10: 694, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31001285

RESUMO

Mesenchymal stromal cells (MSCs) are inherently immunomodulatory through production of inhibiting soluble factors and expression of immunosuppressive cell surface markers. We tested whether activated MSCs qualify for the induction of antigen-specific immune regulation. Bone marrow derived human MSCs were activated by interferon-γ and analyzed for antigen uptake and processing and immune regulatory features including phenotype, immunosuppressive capacity, and metabolic activity. To assess whether activated MSC can modulate adaptive immunity, MSCs were pulsed with islet auto-antigen (GAD65) peptide to stimulate GAD65-specific T-cells. We confirm that inflammatory activation of MSCs increased HLA class II, PD-L1, and intracellular IDO expression, whereas co-stimulatory molecules including CD86 remained absent. MSCs remained locked in their metabolic phenotype, as activation did not alter glycolytic function or mitochondrial respiration. MSCs were able to uptake and process protein. Activated HLA-DR3-expressing MSCs pulsed with GAD65 peptide inhibited proliferation of HLA-DR3-restricted GAD65-specific T-cells, while this HLA class II expression did not induce cellular alloreactivity. Conditioning of antigen-specific T-cells by activated and antigen-pulsed MSCs prevented T-cells to proliferate upon subsequent activation by dendritic cells, even after removal of the MSCs. In sum, activation of MSCs with inflammatory stimuli turns these cells into suppressive cells capable of mediating adaptive regulation of proinflammatory pathogenic T-cells.


Assuntos
Apresentação de Antígeno , Células-Tronco Mesenquimais/imunologia , Linfócitos T/imunologia , Autoantígenos/imunologia , Antígeno B7-2/imunologia , Glutamato Descarboxilase/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Células-Tronco Mesenquimais/citologia , Linfócitos T/citologia
17.
Environ Sci Pollut Res Int ; 26(7): 6890-6897, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30635884

RESUMO

In the present study, the influence of cadmium, copper, and lead on two enzymes often used as biomarkers in toxicological analysis was investigated. Bees were fed with 1 M sucrose solution containing 10-fold serial dilutions of CuCl2 (1000 mg L-1, 100 mg L-1, and 10 mg L-1), CdCl2 (0.1 mg L-1, 0.01 mg L-1, and 0.001 mg L-1), or PbCl2 (10 mg L-1, 1 mg L-1, and 0.1 mg L-1) during 48 h. Our results showed that the total glutathione S-transferase activity was not changed under the influence of cadmium and lead, and it was decreased with the highest concentration of copper. The level of gene expression of the three analyzed classes of glutathione S-transferase was significantly increased with increasing concentrations of copper and cadmium. Lead did not cause significant changes in glutathione S-transferase activity and gene expression, while it showed biphasic effect on acetylcholinesterase activity: lower concentration of lead, 0.1 mg L-1 inhibited and higher dose, 10 mg L-1 induced acetylcholinesterase activity in honey bees. Furthermore, our results showed a significant decrease of the acetylcholinesterase activity in honey bees treated with 0.001 and 0.01 mg L-1 CdCl2. Our results indicate the influence of cadmium, copper, and lead on GST and AChE in the honey bees. These results form the basis for future research on the impact of metallic trace element pollution on honey bees.


Assuntos
Acetilcolinesterase/metabolismo , Abelhas/fisiologia , Poluentes Ambientais/toxicidade , Glutationa Transferase/metabolismo , Metais Pesados/toxicidade , Animais , Bioensaio/métodos , Cádmio/toxicidade , Cobre/toxicidade , Inseticidas , Chumbo/toxicidade , Testes de Toxicidade
18.
Mol Ecol ; 28(4): 731-745, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30575191

RESUMO

Metallothioneins are ubiquitous proteins important in metal homeostasis and detoxification. However, they have not previously been identified in honey bees or other Hymenoptera, where metallothioneins could be of ecophysiological and ecotoxicological significance. Better understanding of the molecular responses to stress induced by toxic metals could contribute to honey bee conservation. In addition, honey bee metallothionein could represent a biomarker for monitoring environmental quality. Here we identify and characterize a metallothionein gene in Apis mellifera (AmMT). AmMT is 1,680 bp long and encodes a 48 amino acids protein with 15 cysteines and no aromatic residues. A metal response element upstream of the start codon, coupled with numerous cis-regulatory elements indicate the functional context of AmMT. Molecular modelling predicts several transition metal binding sites, and comparative phylogenetic analysis revealed five putative metallothionein proteins in three other hymenoptera species. AmMT was characterized by cloning the full-length coding sequence of the putative metallothionein. Recombinant AmMT was found to increase metal tolerance upon overexpression in Escherichia coli supplemented with Cd, Cu or Pb. Finally, in laboratory tests on honey bees, gene expression profiles showed a dose-dependant relationship between Cd, Cu and Pb concentrations present in food and AmMT expression, while field experiments showed induction of AmMT in bees from an industrial site compared to those from an urban area. These studies suggest that AmMT has metal binding properties in agreement with a possible role in metal homeostasis. Further functional and structural characterization of metallothionein in honey bees and other Hymenoptera are necessary.


Assuntos
Abelhas/genética , Metalotioneína/genética , Animais , Abelhas/efeitos dos fármacos , Cádmio/toxicidade , Cobre/toxicidade , Himenópteros/efeitos dos fármacos , Himenópteros/genética , Chumbo/toxicidade
19.
J Insect Physiol ; 109: 107-113, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30030123

RESUMO

The European corn borer (ECB, Ostrinia nubilalis Hbn.) is a major pest in temperate regions of Europe and North America. Fifth instar ECB larvae enter diapause before winter and gradually develop cold hardiness. Here we investigated the combined influence of diapause phase and low temperature on sugar and polyol content in ECB larvae. Larvae in mid-diapause or diapause termination were acclimated at 5 °C, -3°C or -16 °C, and sugar and polyol content was measured using GC-MS. Control GC-MS measurements were conducted on untreated non-diapausing larvae. We detected differences in polyol (glycerol, sorbitol, myo-inositol) and sugar (trehalose, fructose, glucose) levels in diapausing versus non-diapausing larvae. Glycerol and trehalose were the most abundant of all analyzed cryoprotective compounds in diapausing larvae. Exposure of diapausing larvae to decreasing temperatures induced changes in polyol and sugar levels that depended on the phase of diapause. In mid-diapause larvae, decreasing temperatures induced a significant increase in glycerol and a decrease in sorbitol and myo-inositol. In larvae at diapause termination, polyol content was lower and less influenced by decreasing temperatures. In contrast, sugar levels were lower in larvae at mid-diapause versus diapause termination. Exposure of larvae to -16 °C induced a significant increase in the levels of all detected sugars. In particular, glucose levels were significantly higher in larvae at diapause termination following exposure to -16 °C. We propose that this shift toward sugar synthesis following low temperature exposure in larvae at diapause termination is a consequence of NADPH dependent polyol synthesis, and may be a mechanism for preservation of carbon reserves needed for post-diapause development.


Assuntos
Diapausa de Inseto/fisiologia , Mariposas/fisiologia , Polímeros/metabolismo , Açúcares/metabolismo , Animais , Larva/química , Larva/fisiologia , Mariposas/crescimento & desenvolvimento , Temperatura
20.
PLoS One ; 13(7): e0199859, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29975728

RESUMO

The relationships between nutrition, metabolic response, early growth and later body weight have been investigated in human studies. The aim of this follow-up study was to assess the long-term effect of infant feeding on growth and to study whether the infant metabolome at the age of 4 months might predict anthropometry at 4 years of age. The Belgrade-Munich infant milk trial (BeMIM) was a randomized controlled trial in which healthy term infants received either a protein-reduced infant formula (1.89 g protein/100 kcal) containing alpha-lactalbumin enriched whey and long-chain polyunsaturated fatty acids (LC-PUFA), or a standard formula (2.2 g protein/100 kcal) without LC-PUFA, focusing on safety and suitability. Non-randomized breastfed infants were used as a reference group. Of the 259 infants that completed the BeMIM study at the age of 4 months (anthropometry assessment and blood sampling), 187 children participated in a follow-up visit at 4 years of age. Anthropometry including weight, standing height, head circumference, and percent body fat was determined using skinfolds (triceps, subscapular) and bioelectrical impedance analysis. Plasma metabolite concentration, collected in samples at the age of 4 months, was measured using flow-injection tandem mass spectrometry. A linear regression model was applied to estimate the associations between each metabolite and growth with metabolites as an independent variable. At 4 years of age, there were no significant group differences in anthropometry and body composition between formula groups. Six metabolites (Asn, Lys, Met, Phe, Trp, Tyr) measured at 4 months of age were significantly associated with changes in weight-for-age z-score between 1 to 4 months of age and BMI-for-age z-score (Tyr only), after adjustment for feeding group. No correlation was found between measured metabolites and long-term growth (up to 4 years of age). No long-term effects of early growth patterns were shown on anthropometry at 4 years of age. The composition of infant formula influences the metabolic profile and early growth, while long-term programming effects were not observed in this study.


Assuntos
Antropometria , Desenvolvimento Infantil , Fórmulas Infantis/química , Fenômenos Fisiológicos da Nutrição do Lactente , Metaboloma , Composição Corporal , Método Duplo-Cego , Seguimentos , Humanos , Lactente , Fórmulas Infantis/análise
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