RESUMO
Over the past years, there has been an increasing concern about the occurrence of antineoplastic drugs in water bodies. The incomplete removal of these pharmaceuticals from wastewaters has been confirmed by several scientists, making it urgent to find a reliable technique or a combination of techniques capable to produce clean and safe water. In this work, the combination of nanofiltration and ozone (O3)-based processes (NF + O3, NF + O3/H2O2 and NF + O3/H2O2/UVA) was studied aiming to produce clean water from wastewater treatment plant (WWTP) secondary effluents to be safely discharged into water bodies, reused in daily practices such as aquaculture activities or for recharging aquifers used as abstraction sources for drinking water production. Nanofiltration was performed in a pilot-scale unit and O3-based processes in a continuous-flow column. The peroxone process (O3/H2O2) was considered the most promising technology to be coupled to nanofiltration, all the target pharmaceuticals being removed at an extent higher than 98% from WWTP secondary effluents, with a DOC reduction up to 92%. The applicability of the clean water stream for recharging aquifers used as abstraction sources for drinking water production was supported by a risk assessment approach, regarding the final concentrations of the target pharmaceuticals. Moreover, the toxicity of the nanofiltration retentate, a polluted stream generated from the nanofiltration system, was greatly decreased after the application of the peroxone process, which evidences the positive impact on the environment of implementing a NF + O3/H2O2 process.
Assuntos
Antineoplásicos , Água Potável , Ozônio , Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Peróxido de Hidrogênio , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Preparações Farmacêuticas , OxirreduçãoRESUMO
Eighteen per-and polyfluoroalkyl substances (PFASs) were investigated in surface waters of four river basins in Portugal (Ave, Leça, Antuã, and Cértima) during the dry and wet seasons. All sampling sites showed contamination in at least one of the seasons. In the dry season, perfluorooctanoate acid (PFOA) and perfluoro-octane sulfonate (PFOS), were the most frequent PFASs, while during the wet season these were PFOA and perfluobutane-sulfonic acid (PFBS). Compounds detected at higher concentrations were PFOS (22.6 ng L-1) and perfluoro-butanoic acid (PFBA) (22.6 ng L-1) in the dry and wet seasons, respectively. Moreover, the prospective environmental risks of PFASs, detected at higher concentrations, were evaluated based on the Risk Quotient (RQ) classification, which comprises acute and chronic toxicity. The results show that the RQ values of eight out of the nine PFASs were below 0.01, indicating low risk to organisms at different trophic levels in the four rivers in both seasons, wet and dry. Nevertheless, in the specific case of perfluoro-tetradecanoic acid (PFTeA), the RQ values calculated exceeded 1 for fish (96 h) and daphnids (48 h), indicating a high risk for these organisms. Furthermore, the RQ values were higher than 0.1, indicating a medium risk for fish, daphnids and green algae (96 h).
Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Poluentes Químicos da Água , Animais , Rios , Ácidos Alcanossulfônicos/análise , Portugal , Estudos Prospectivos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Fluorocarbonos/análise , Alcanossulfonatos , PeixesRESUMO
Aquaculture is the fastest growing animal food-producing sector. Water is the central resource for aquaculture, and it is essential that its quality be preserved. Micropollutants (MPs) can reach aquaculture through anthropogenic addition or inlet water, and may cause harmful effects such as endocrine disruption and antibiotic resistance, adversely affecting the fish species being farmed. Furthermore, the discharge of aquaculture effluents into the environment may contribute to the deterioration of water courses. In this sense, the implementation of environmentally responsible measures in aquaculture farms is imperative for the protection of ecosystems and human health. The European Commission (EC) has recently launched a guiding document promoting ecological aquaculture practices; however, options for water treatment are still lacking. Conventional processes are not designed to deal with MPs; this review article consolidates relevant information on the application of advanced oxidation technologies (AOTs) and constructed wetlands (CWs) as potential strategies in this regard. Although 161 studies on the application of AOTs or CWs in aquaculture have already been published, only 34 focused on MPs (28 on AOTs and 6 on CWs), whereas the others reported the removal of contaminants such as bacteria, organic matter, solids and inorganic ions. No study coupling both treatments has been reported to date for the removal of MPs from aquaculture waters. AOTs and CWs are prospective alternatives for the treatment of aquacultural aqueous matrices. However, the type of aquaculture activity and the specifications of these available technologies should be considered while selecting the most suitable treatment option.
Assuntos
Poluentes Químicos da Água , Áreas Alagadas , Animais , Aquicultura , Ecossistema , Humanos , Estudos Prospectivos , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água/análiseRESUMO
Despite the well-documented effect of castration in thymic regeneration, the singular contribution of the bone marrow (BM) versus the thymus to this process remains unclear. The chief role of IL-7 in pre- and intrathymic stages of T lymphopoiesis led us to investigate the impact of disrupting this cytokine during thymic rebound induced by androgen blockade. We found that castration promoted thymopoiesis in young and aged wild-type mice. In contrast, only young germline IL-7-deficient (Il7-/- ) mice consistently augmented thymopoiesis after castration. The increase in T cell production was accompanied by the expansion of the sparse medullary thymic epithelial cell and the peripheral T cell compartment in young Il7-/- mice. In contrast to young Il7-/- and wild-type mice, the poor thymic response of aged Il7-/- mice after castration was associated with a defect in the expansion of BM hematopoietic progenitors. These findings suggest that BM-derived T cell precursors contribute to thymic rebound driven by androgen blockade. To assess the role of IL-7 within the thymus, we generated mice with conditional deletion of IL-7 (Il7 conditional knockout [cKO]) in thymic epithelial cells. As expected, Il7cKO mice presented a profound defect in T cell development while maintaining an intact BM hematopoietic compartment across life. Unlike Il7-/- mice, castration promoted the expansion of BM precursors and enhanced thymic activity in Il7cKO mice independently of age. Our findings suggest that the mobilization of BM precursors acts as a prime catalyst of castration-driven thymopoiesis.
Assuntos
Células-Tronco Hematopoéticas/imunologia , Linfopoese/fisiologia , Timo/imunologia , Androgênios/metabolismo , Animais , Células da Medula Óssea/imunologia , Castração , Diferenciação Celular/fisiologia , Interleucina-7/deficiência , Interleucina-7/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Timo/citologiaRESUMO
Thymic epithelial cells (TECs) provide crucial microenvironments for T-cell development and tolerance induction. As the regular function of the thymus declines with age, it is of fundamental and clinical relevance to decipher new determinants that control TEC homeostasis in vivo. Beyond its recognized tumor suppressive function, p53 controls several immunoregulatory pathways. To study the cell-autonomous role of p53 in thymic epithelium functioning, we developed and analyzed mice with conditional inactivation of Trp53 in TECs (p53cKO). We report that loss of p53 primarily disrupts the integrity of medullary TEC (mTEC) niche, a defect that spreads to the adult cortical TEC compartment. Mechanistically, we found that p53 controls specific and broad programs of mTEC differentiation. Apart from restraining the expression and responsiveness of the receptor activator of NF-κB (RANK), which is central for mTEC differentiation, deficiency of p53 in TECs altered multiple functional modules of the mTEC transcriptome, including tissue-restricted antigen expression. As a result, p53cKO mice presented premature defects in mTEC-dependent regulatory T-cell differentiation and thymocyte maturation, which progressed to a failure in regular and regenerative thymopoiesis and peripheral T-cell homeostasis in the adulthood. Lastly, peripheral signs of altered immunological tolerance unfold in mutant mice and in immunodeficient mice that received p53cKO-derived thymocytes. Our findings position p53 as a novel molecular determinant of thymic epithelium function throughout life.
Assuntos
Diferenciação Celular/imunologia , Células Epiteliais/imunologia , Linfócitos T Reguladores/imunologia , Timócitos/imunologia , Proteína Supressora de Tumor p53/imunologia , Animais , Diferenciação Celular/genética , Células Epiteliais/citologia , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/citologia , Timócitos/citologia , Timo , Proteína Supressora de Tumor p53/genéticaRESUMO
IFN-γ is known to be predominantly produced by lymphoid cells such as certain subsets of T cells, NK cells, and other group 1 innate lymphoid cells. In this study, we used IFN-γ reporter mouse models to search for additional cells capable of secreting this cytokine. We identified a novel and rare population of nonconventional IFN-γ-producing cells of hematopoietic origin that were characterized by the expression of Thy1.2 and the lack of lymphoid, myeloid, and NK lineage markers. The expression of IFN-γ by this population was higher in the liver and lower in the spleen. Furthermore, these cells were present in mice lacking both the Rag2 and the common γ-chain (γc) genes (Rag2-/-γc-/-), indicating their innate nature and their γc cytokine independence. Rag2-/-γc-/- mice are as resistant to Mycobacterium avium as Rag2-/- mice, whereas Rag2-/- mice lacking IFN-γ are more susceptible than either Rag2-/- or Rag2-/-γc-/- These lineage-negative CD45+/Thy1.2+ cells are found within the mycobacterially induced granulomatous structure in the livers of infected Rag2-/-γc-/- animals and are adjacent to macrophages that expressed inducible NO synthase, suggesting a potential protective role for these IFN-γ-producing cells. Accordingly, Thy1.2-specific mAb administration to infected Rag2-/-γc-/- animals increased M. avium growth in the liver. Overall, our results demonstrate that a population of Thy1.2+ non-NK innate-like cells present in the liver expresses IFN-γ and can confer protection against M. avium infection in immunocompromised mice.
Assuntos
Células-Tronco Hematopoéticas/imunologia , Imunidade Inata , Interferon gama/biossíntese , Interferon gama/genética , Subunidade gama Comum de Receptores de Interleucina/imunologia , Animais , Anticorpos Monoclonais/administração & dosagem , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/imunologia , Granuloma/imunologia , Granuloma/microbiologia , Hospedeiro Imunocomprometido/imunologia , Interferon gama/imunologia , Subunidade gama Comum de Receptores de Interleucina/deficiência , Subunidade gama Comum de Receptores de Interleucina/genética , Células Matadoras Naturais/imunologia , Antígenos Comuns de Leucócito/genética , Antígenos Comuns de Leucócito/imunologia , Fígado/citologia , Fígado/imunologia , Fígado/microbiologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mycobacterium avium/crescimento & desenvolvimento , Mycobacterium avium/imunologia , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Baço/citologia , Baço/imunologia , Antígenos Thy-1/genética , Antígenos Thy-1/imunologiaRESUMO
Cortical (cTEC) and medullary (mTEC) thymic epithelial cells establish key microenvironments for T-cell differentiation and arise from thymic epithelial cell progenitors (TEP). However, the nature of TEPs and the mechanism controlling their stemness in the postnatal thymus remain poorly defined. Using TEC clonogenic assays as a surrogate to survey TEP activity, we found that a fraction of cTECs generates specialized clonal-derived colonies, which contain cells with sustained colony-forming capacity (ClonoTECs). These ClonoTECs are EpCAM+MHCII-Foxn1lo cells that lack traits of mature cTECs or mTECs but co-express stem-cell markers, including CD24 and Sca-1. Supportive of their progenitor identity, ClonoTECs reintegrate within native thymic microenvironments and generate cTECs or mTECs in vivo. Strikingly, the frequency of cTECs with the potential to generate ClonoTECs wanes between the postnatal and young adult immunocompetent thymus, but it is sustained in alymphoid Rag2-/-Il2rg-/- counterparts. Conversely, transplantation of wild-type bone marrow hematopoietic progenitors into Rag2-/-Il2rg-/- mice and consequent restoration of thymocyte-mediated TEC differentiation diminishes the frequency of colony-forming units within cTECs. Our findings provide evidence that the cortical epithelium contains a reservoir of epithelial progenitors whose abundance is dynamically controlled by continual interactions with developing thymocytes across lifespan.
Assuntos
Células Epiteliais/citologia , Células-Tronco/fisiologia , Timócitos/fisiologia , Timo/citologia , Animais , Diferenciação Celular , Células Clonais , Células Epiteliais/fisiologia , Humanos , Ativação Linfocitária , Camundongos , Timócitos/imunologia , Timo/metabolismoRESUMO
The development of effective T-cell-based immunotherapies to treat infection, cancer, and autoimmunity should incorporate the ground rules that control differentiation of T cells in the thymus. Within the thymus, thymic epithelial cells (TECs) provide microenvironments supportive of the generation and selection of T cells that are responsive to pathogen-derived antigens, and yet tolerant to self-determinants. Defects in TEC differentiation cause syndromes that range from immunodeficiency to autoimmunity, which makes the study of TECs of fundamental and clinical importance to comprehend how immunity and tolerance are balanced. Critical to tolerance induction are medullary thymic epithelial cells (mTECs), which purge autoreactive T cells, or redirect them to a regulatory T-cell lineage. In this issue of the European Journal of Immunology, studies by Baik et al. and Mayer et al. [Eur. J. Immunol. 2016. 46: XXXX-XXXX and 46: XXXX-XXXX]) document novel spatial-temporal singularities in the lineage specification and maintenance of mTECs. While Baik et al. define a developmental checkpoint during mTEC specification in the embryo, Mayer et al. reveal that the generation and maintenance of the adult mTEC compartment is temporally controlled in vivo. The two reports described new developmentally related, but temporally distinct principles that underlie the homeostasis of the thymic medulla across life.
Assuntos
Diferenciação Celular/imunologia , Células Epiteliais/imunologia , Autoimunidade , Humanos , Linfócitos T Reguladores , TimoRESUMO
The rapid development of nanotechnologies and increased production and use of nanomaterials raise concerns about their potential toxic effects for human health and environment. To evaluate the biological effects of nanomaterials, a set of reliable and reproducible methods and development of standard operating procedures (SOPs) is required. In the framework of the European FP7 NanoValid project, three different cell viability assays (MTS, ATP content, and caspase-3/7 activity) with different readouts (absorbance, luminescence and fluorescence) and two immune assays (ELISA of pro-inflammatory cytokines IL1-ß and TNF-α) were evaluated by inter-laboratory comparison. The aim was to determine the suitability and reliability of these assays for nanosafety assessment. Studies on silver and copper oxide nanoparticles (NPs) were performed, and SOPs for particle handling, cell culture, and in vitro assays were established or adapted. These SOPs give precise descriptions of assay procedures, cell culture/seeding conditions, NPs/positive control preparation and dilutions, experimental well plate preparation, and evaluation of NPs interference. The following conclusions can be highlighted from the pan-European inter-laboratory studies: Testing of NPs interference with the toxicity assays should always be conducted. Interference tests should be designed as close as possible to the cell exposure conditions. ATP and MTS assays gave consistent toxicity results with low inter-laboratory variability using Ag and CuO NPs and different cell lines and therefore, could be recommended for further validation and standardization. High inter-laboratory variability was observed for Caspase 3/7 assay and ELISA for IL1-ß and TNF-α measurements.
Assuntos
Cobre/toxicidade , Citocinas/metabolismo , Laboratórios/normas , Nanopartículas Metálicas/toxicidade , Prata/toxicidade , Testes de Toxicidade/normas , Bioensaio/métodos , Bioensaio/normas , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Europa (Continente) , Humanos , Nanopartículas Metálicas/química , Tamanho da Partícula , Reprodutibilidade dos Testes , Prata/química , Propriedades de Superfície , Testes de Toxicidade/métodosRESUMO
Organic micropollutants present in drinking water (DW) may cause adverse effects for public health, and so reliable analytical methods are required to detect these pollutants at trace levels in DW. This work describes the first green analytical methodology for multi-class determination of 21 pollutants in DW: seven pesticides, an industrial compound, 12 pharmaceuticals, and a metabolite (some included in Directive 2013/39/EU or Decision 2015/495/EU). A solid-phase extraction procedure followed by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry (offline SPE-UHPLC-MS/MS) method was optimized using eco-friendly solvents, achieving detection limits below 0.20 ng L-1. The validated analytical method was successfully applied to DW samples from different sources (tap, fountain, and well waters) from different locations in the north of Portugal, as well as before and after bench-scale UV and ozonation experiments in spiked tap water samples. Thirteen compounds were detected, many of them not regulated yet, in the following order of frequency: diclofenac > norfluoxetine > atrazine > simazine > warfarin > metoprolol > alachlor > chlorfenvinphos > trimethoprim > clarithromycin ≈ carbamazepine ≈ PFOS > citalopram. Hazard quotients were also estimated for the quantified substances and suggested no adverse effects to humans. Graphical Abstract Occurrence and removal of multi-class micropollutants in drinking water, analyzed by an eco-friendly LC-MS/MS method.
Assuntos
Água Potável/análise , Monitoramento Ambiental/métodos , Água Doce/análise , Química Verde/métodos , Poluentes Químicos da Água/análise , Poços de Água , Cromatografia Líquida/métodos , Monitoramento Ambiental/instrumentação , Química Verde/instrumentação , Portugal , Extração em Fase Sólida , Espectrometria de Massas em Tandem/métodosRESUMO
In the current paper, a new strategy for risk assessment of nanomaterials is described, which builds upon previous project outcomes and is developed within the FP7 NANoREG project. NANoREG has the aim to develop, for the long term, new testing strategies adapted to a high number of nanomaterials where many factors can affect their environmental and health impact. In the proposed risk assessment strategy, approaches for (Quantitative) Structure Activity Relationships ((Q)SARs), grouping and read-across are integrated and expanded to guide the user how to prioritise those nanomaterial applications that may lead to high risks for human health. Furthermore, those aspects of exposure, kinetics and hazard assessment that are most likely to be influenced by the nanospecific properties of the material under assessment are identified. These aspects are summarised in six elements, which play a key role in the strategy: exposure potential, dissolution, nanomaterial transformation, accumulation, genotoxicity and immunotoxicity. With the current approach it is possible to identify those situations where the use of nanospecific grouping, read-across and (Q)SAR tools is likely to become feasible in the future, and to point towards the generation of the type of data that is needed for scientific justification, which may lead to regulatory acceptance of nanospecific applications of these tools.
Assuntos
Nanopartículas/toxicidade , Nanotecnologia/métodos , Testes de Toxicidade/métodos , Animais , Biotransformação , Carga Corporal (Radioterapia) , Qualidade de Produtos para o Consumidor , Humanos , Sistema Imunitário/efeitos dos fármacos , Estrutura Molecular , Testes de Mutagenicidade , Nanopartículas/química , Nanopartículas/metabolismo , Segurança do Paciente , Relação Quantitativa Estrutura-Atividade , Medição de Risco , SolubilidadeRESUMO
Natural organic compounds such as phytoestrogens and phytosterols found in various plants, as well as mycotoxins produced by fungi, can be found in aquatic environments. The aim of this study was to investigate the occurrence of three different classes of natural estrogenic compounds, i.e., phytoestrogens, phytosterols and mycotoxins, in estuarine water samples from the Ave River estuary. For that, water samples were collected at five sampling points distributed along the estuary at low tide, during 1 year, processed by solid-phase extraction (SPE) and analyzed by gas chromatography coupled to mass spectrometry (GC-MS). To correlate the presence of phytoestrogens and phytosterols in the estuarine water, local flora was collected on riverside. Trace elements content and physicochemical parameters such as nutrients and dissolved oxygen were also determined seasonally at each sampling point, to give insights for the evaluation of water quality and anthropogenic pressure. Both phytoestrogens and phytosterols showed a seasonal variation, with the highest values observed in spring and summer and the lowest in winter. Daidzein (DAID) was found up to 404.0 ng L(-1) in spring and coumestrol (COUM) was found up to 165.0 ng L(-1) in summer. The mycotoxin deoxynivalenol (DON) was ubiquitously determined with values ranging from 59.5 to 642.4 ng L(-1). Nutrients and metals distribution and concentration varied among sampling stations and seasons. This study revealed for the first time the presence of mycotoxins, various classes of phytoestrogens and stigmasterol (STG) in estuarine water from the Ave River (Portugal), and the evaluation of the water quality confirmed that this estuary is still highly impacted by anthropogenic activities.
Assuntos
Monitoramento Ambiental/métodos , Estrogênios/análise , Micotoxinas/análise , Fitoestrógenos/análise , Fitosteróis/análise , Rios/química , Poluentes Químicos da Água/análise , Disruptores Endócrinos/análise , Disruptores Endócrinos/química , Estrogênios/química , Cromatografia Gasosa-Espectrometria de Massas , Micotoxinas/química , Fitoestrógenos/química , Fitosteróis/química , Portugal , Estações do Ano , Oligoelementos/análise , Oligoelementos/química , Poluentes Químicos da Água/química , Qualidade da ÁguaRESUMO
Lymphotoxin-mediated activation of the lymphotoxin-ß receptor (LTßR; LTBR) has been implicated in cancer, but its role in T-cell acute lymphoblastic leukaemia (T-ALL) has remained elusive. Here we show that the genes encoding lymphotoxin (LT)-α and LTß (LTA, LTB) are expressed in T-ALL patient samples, mostly of the TAL/LMO molecular subtype, and in the TEL-JAK2 transgenic mouse model of cortical/mature T-ALL (Lta, Ltb). In these mice, expression of Lta and Ltb is elevated in early stage T-ALL. Surface LTα1 ß2 protein is expressed in primary mouse T-ALL cells, but only in the absence of microenvironmental LTßR interaction. Indeed, surface LT expression is suppressed in leukaemic cells contacting Ltbr-expressing but not Ltbr-deficient stromal cells, both in vitro and in vivo, thus indicating that dynamic surface LT expression in leukaemic cells depends on interaction with its receptor. Supporting the notion that LT signalling plays a role in T-ALL, inactivation of Ltbr results in a significant delay in TEL-JAK2-induced leukaemia onset. Moreover, young asymptomatic TEL-JAK2;Ltbr(-/-) mice present markedly less leukaemic thymocytes than age-matched TEL-JAK2;Ltbr(+/+) mice and interference with LTßR function at this early stage delayed T-ALL development. We conclude that LT expression by T-ALL cells activates LTßR signalling in thymic stromal cells, thus promoting leukaemogenesis.
Assuntos
Receptor beta de Linfotoxina/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Linhagem da Célula/genética , Expressão Gênica/genética , Humanos , Imunofenotipagem , Janus Quinase 2/genética , Receptor beta de Linfotoxina/genética , Receptor beta de Linfotoxina/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Transdução de Sinais , Microambiente Tumoral/genéticaRESUMO
Cortical and medullary thymic epithelial cells (cTECs and mTECs, respectively) provide inductive microenvironments for T-cell development and selection. The differentiation pathway of cTEC/mTEC lineages downstream of common bipotent progenitors at discrete stages of development remains unresolved. Using IL-7/CCRL1 dual reporter mice that identify specialized TEC subsets, we show that the stepwise acquisition of chemokine (C-C motif) receptor-like 1 (CCRL1) is a late determinant of cTEC differentiation. Although cTECs expressing high CCRL1 levels (CCRL1(hi) ) develop normally in immunocompetent and Rag2(-/-) thymi, their differentiation is partially blocked in Rag2(-/-) Il2rg(-/-) counterparts. These results unravel a novel checkpoint in cTEC maturation that is regulated by the cross-talk between TECs and immature thymocytes. Additionally, we identify new Ulex europaeus agglutinin 1 (UEA)(+) mTEC subtypes expressing intermediate CCRL1 levels (CCRL1(int) ) that conspicuously emerge in the postnatal thymus and differentially express Tnfrsf11a, Ccl21, and Aire. While rare in fetal and in Rag2(-/-) thymi, CCRL1(int) mTECs are restored in Rag2(-/-) Marilyn TCR-Tg mice, indicating that the appearance of postnatal-restricted mTECs is closely linked with T-cell selection. Our findings suggest that alternative temporally restricted routes of new mTEC differentiation contribute to the establishment of the medullary niche in the postnatal thymus.
Assuntos
Diferenciação Celular/imunologia , Células Epiteliais/citologia , Receptores CCR/biossíntese , Timo/citologia , Timo/crescimento & desenvolvimento , Animais , Biomarcadores/análise , Citometria de Fluxo , Camundongos , Camundongos Knockout , Análise de Sequência com Séries de Oligonucleotídeos , Receptores CCR/imunologia , Linfócitos T/citologia , Linfócitos T/imunologia , Timo/imunologia , TranscriptomaRESUMO
Thymic epithelial cells (TECs) provide key instructive signals for T-cell differentiation. Thymic cortical (cTECs) and medullary (mTECs) epithelial cells constitute two functionally distinct microenvironments for T-cell development, which derive from a common bipotent TEC progenitor. While seminal studies have partially elucidated events downstream of bipotent TECs in relation to the emergence of mTECs and their progenitors, the control and timing of the emergence of the cTEC lineage, particularly in relation to that of mTEC progenitors, has remained elusive. In this review, we describe distinct models that explain cTEC/mTEC lineage divergence from common bipotent progenitors. In particular, we summarize recent studies in mice providing evidence that mTECs, including the auto-immune regulator(+) subset, derive from progenitors initially endowed with phenotypic properties typically associated with the cTEC lineage. These observations support a novel "serial progression" model of TEC development, in which progenitors serially acquire cTEC lineage markers, prior to their commitment to the mTEC differentiation pathway. Gaining a better understanding of the phenotypic properties of early stages in TEC progenitor development should help in determining the mechanisms regulating cTEC/mTEC lineage development, and in strategies aimed at thymus reconstitution involving TEC therapy.
Assuntos
Células Epiteliais/imunologia , Imunoterapia/métodos , Células Progenitoras Linfoides/imunologia , Modelos Imunológicos , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Timo/imunologia , Animais , Autoimunidade , Comunicação Celular/imunologia , Diferenciação Celular , Linhagem da Célula , Humanos , Imunoterapia/tendências , CamundongosRESUMO
Thymic epithelial cells (TECs) help orchestrate thymopoiesis, and TEC differentiation relies on bidirectional interactions with thymocytes. Although the molecular mediators that stimulate medullary thymic epithelial cell (mTEC) maturation are partially elucidated, the signals that regulate cortical thymic epithelial cell (cTEC) homeostasis remain elusive. Using IL-7 reporter mice, we show that TECs coexpressing high levels of IL-7 (Il7(YFP+) TECs) reside within a subset of CD205(+)Ly51(+)CD40(low) cTECs that coexpresses Dll4, Ccl25, Ccrl1, Ctsl, Psmb11, and Prss16 and segregates from CD80(+)CD40(high) mTECs expressing Tnfrsf11a, Ctss, and Aire. As the frequency of Il7(YFP+) TECs gradually declines as mTEC development unfolds, we explored the relationship between Il7(YFP+) TECs and mTECs. In thymic organotypic cultures, the thymocyte-induced reduction in Il7(YFP+) TECs dissociates from the receptor activator of NF-κB-mediated differentiation of CD80(+) mTECs. Still, Il7(YFP+) TECs can generate some CD80(+) mTECs in a stepwise differentiation process via YFP(-)Ly51(low)CD80(low) intermediates. Il7(YFP+) TECs are sustained in Rag2(-/-) mice, even following in vivo anti-CD3ε treatment that mimics the process of pre-TCR ß-selection of thymocytes to the double positive (DP) stage. Using Marilyn-Rag2(-/-) TCR transgenic, we find that positive selection into the CD4 lineage moderately reduces the frequency of Il7(YFP+) TECs, whereas negative selection provokes a striking loss of Il7(YFP+) TECs. These results imply that the strength of MHC/peptide-TCR interactions between TECs and thymocytes during selection constitutes a novel rheostat that controls the maintenance of IL-7-expressing cTECs.
Assuntos
Células Epiteliais/imunologia , Interleucina-7/biossíntese , Timo/imunologia , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos CD/metabolismo , Antígeno B7-1/metabolismo , Complexo CD3/imunologia , Antígenos CD40/metabolismo , Proteínas de Ligação ao Cálcio , Catepsina L/biossíntese , Catepsinas/biossíntese , Diferenciação Celular/imunologia , Movimento Celular , Células Cultivadas , Quimiocinas CC/biossíntese , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Células Epiteliais/metabolismo , Homeostase , Interleucina-7/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/biossíntese , Lectinas Tipo C/metabolismo , Ativação Linfocitária , Proteínas de Membrana/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Antígenos de Histocompatibilidade Menor , Técnicas de Cultura de Órgãos , Receptor Ativador de Fator Nuclear kappa-B/biossíntese , Receptor Ativador de Fator Nuclear kappa-B/metabolismo , Receptores CCR/biossíntese , Receptores de Superfície Celular/metabolismo , Serina Endopeptidases/biossíntese , Timócitos/metabolismo , Timo/metabolismo , Fatores de Transcrição/biossíntese , Proteína AIRERESUMO
The growing body of evidence links exposure to particulate matter pollutants with an increased risk of neurodegenerative diseases. In the present study, we investigated whether diesel exhaust particles can induce neurobehavioral alterations associated with neurodegenerative effects on glutamatergic and dopaminergic neurons in Caenorhabditis elegans (C. elegans). Exposure to DEP at concentrations of 0.167 µg/cm2 and 1.67 µg/cm2 resulted in significant developmental delays and altered locomotion behaviour. These effects were accompanied by discernible alterations in the expressions of antioxidant genes sod-3 and gst-4 observed in transgenic strains. Behaviour analysis demonstrated a significant reduction in average speed (p < 0.001), altered paths, and decreased swimming activities (p < 0.01), particularly at mid and high doses. Subsequent assessment of neurodegeneration markers in glutamatergic (DA1240) and dopaminergic (BZ555) transgenic worms revealed notable glutamatergic neuron degeneration at 0.167 µg/cm2 (â¼30 % moderate, â¼20 % advanced) and 1.67 µg/cm2 (â¼28 % moderate, â¼24 % advanced, p < 0.0001), while dopaminergic neurons exhibited structural deformities (â¼16 %) without significant degeneration in terms of blebs and breaks. Furthermore, in silico docking simulations suggest the presence of an antagonistic competitive inhibition induced by DEP in the evaluated neuro-targets, stronger for the glutamatergic transporter than for the dopaminergic receptor from the comparative binding affinity point of view. The results underscore DEP's distinctive neurodegenerative effects and suggest a link between locomotion defects and glutamatergic neurodegeneration in C. elegans, providing insights into environmental health risks assessment.
Assuntos
Caenorhabditis elegans , Neurônios Dopaminérgicos , Emissões de Veículos , Animais , Caenorhabditis elegans/efeitos dos fármacos , Neurônios Dopaminérgicos/efeitos dos fármacos , Emissões de Veículos/toxicidade , Material Particulado/toxicidade , Animais Geneticamente Modificados , Ácido Glutâmico/metabolismo , Locomoção/efeitos dos fármacos , Doenças Neurodegenerativas/induzido quimicamente , Poluentes Atmosféricos/toxicidadeRESUMO
The sensory quality of drinking water, and particularly its taste and odor (T&O) is a key determinant of consumer acceptability, as consumers evaluate water by their senses. Some of the conventional treatment processes to control compounds which impart unpleasant T&O have limitations because of their low efficiency and/or high costs. Therefore, there is a great need to develop an effective process for removing T&O compounds without secondary concerns. The primary objective of this study was to assess for the first time the effectiveness of spirulina-based carbon materials in removing geosmin (GSM) and 2-methylisoborneol (2-MIB) from water, two commonly occurring natural T&O compounds. The efficiency of the materials to remove environmentally relevant concentrations of GSM and 2-MIB (ng L-1) from ultrapure and raw water was investigated using a sensitive headspace solid-phase microextraction coupled with gas chromatography mass spectrometry (HS-SPME-GC/MS) method. Moreover, the genotoxic and cytotoxic effects of the spirulina-based materials were assessed for the first time to evaluate their safety and their potential in the treatment of water for human consumption. Based on the results, spirulina-based materials were found to be promising for drinking water treatment applications, as they did not exert geno-cytotoxic effects on human cells, while presenting high efficiency in removing GSM and 2-MIB from water.
Assuntos
Água Potável , Odorantes , Spirulina , Paladar , Poluentes Químicos da Água , Purificação da Água , Água Potável/química , Odorantes/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Naftóis , Humanos , Canfanos , Adsorção , Microextração em Fase Sólida/métodos , Carbono , Cromatografia Gasosa-Espectrometria de MassasRESUMO
Butylone (BTL) is a chiral synthetic cathinone available as a racemate and reported as contaminant in wastewater effluents. However, there are no studies on its impact on ecosystems and possible enantioselectivity in ecotoxicity. This work aimed to evaluate: (i) the possible ecotoxicity of BTL as racemate or its isolated (R)- and (S)- enantiomers using Daphnia magna; and (ii) the efficiency of advanced oxidation technologies (AOTs) in the removal of BTL and reduction of toxic effects caused by wastewaters. Enantiomers of BTL were obtained by liquid chromatography (LC) using a chiral semi-preparative column. Enantiomeric purity of each enantiomer was > 97 %. For toxicity assessment, a 9-day sub-chronic assay was performed with the racemate (at 0.10, 1.0 or 10 µg L-1) or each enantiomer (at 0.10 or 1.0 µg L-1). Changes in morphophysiological, behavioural, biochemical and reproductive endpoints were observed, which were dependent on the form of the substance and life stage of the organism (juvenile or adult). Removal rates of BTL in spiked wastewater (10 µg L-1) treated with different AOTs (ultraviolet, UV; ozonation, O3; and UV/O3) were similar and lower than 29 %. The 48 h D. magna acute toxicity assays demonstrated a reduction in the toxicity of the treated spiked effluents, but no differences were found amongst AOTs treatments. These results warn for the contamination and negative impact of BTL on ecosystems and highlight the need for efficient removal processes.
Assuntos
Daphnia , Oxirredução , Poluentes Químicos da Água , Daphnia/efeitos dos fármacos , Animais , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/química , Estereoisomerismo , Águas Residuárias/química , Águas Residuárias/toxicidade , Daphnia magnaRESUMO
Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.