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1.
World Allergy Organ J ; 16(11): 100839, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020282

RESUMO

Introduction: As the only market-authorized allergen immunotherapy (AIT) for peanut allergy is accompanied by a high risk of side effects and mainly induces robust desensitization without sustained efficacy, novel treatment options are required. Peanut-specific plant-derived eBioparticles (eBPs) surface expressing Ara h 2 at high density have been shown to be very hypoallergenic. Here, we assessed the dendritic cell (DC)-activating and T cell polarization capacity of these peanut-specific eBPs. Methods: Route and kinetics of eBP uptake were studied by (imaging) flow cytometry using monocyte-derived DCs incubated with fluorescently-labelled Ara h 2 eBPs or natural Ara h 2 (nAra h 2) in the presence or absence of inhibitors that block pathways involved in macropinocytosis, phagocytosis, and/or receptor-mediated uptake. DC activation was monitored by flow cytometry (maturation marker expression) and ELISA (cytokine production). T cell polarization was assessed by co-culturing DCs exposed to Ara h 2 eBPs or nAra h 2 with naïve CD4+ T cells, followed by flow cytometry assessment of intracellular IFNγ+ (Th1) and IL-13+ (Th2), and CD25+CD127-Foxp3+ regulatory T cells (Tregs). The suppressive activity of Tregs was tested using a suppressor assay. Results: Ara h 2 eBPs were taken up by DCs through actin-dependent pathways. They activated DCs demonstrated by an induced expression of CD83 and CD86, and production of TNFα, IL-6, and IL-10. eBP-treated DCs polarized naïve CD4+ T cells towards Th1 cells, while reducing Th2 cell development. Furthermore, eBP-treated DCs induced reduced the frequency of Foxp3+ Tregs but did not significantly affect T cell IL-10 production or T cells with suppressive capacity. In contrast, DC activation and Th1 cell polarization were not observed for nAra h 2. Conclusion: Ara h 2 eBPs activate DCs that subsequently promote Th1 cell polarization and reduce Th2 cell polarization. These characteristics mark Ara h 2 eBPs as a promising novel candidate for peanut AIT.

2.
J Pharm Sci ; 111(4): 1081-1091, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35114209

RESUMO

Dendritic cells (DCs) control adaptive immunity and are therefore attractive for in vivo targeting to either induce immune activation or tolerance, depending on disease. Liposomes, nanoparticles comprised of a lipid bi-layer, provide a nanoplatform for loading disease-relevant antigen, adjuvant and DC-targeting molecules simultaneously. However, it is yet not fully understood how liposomal formulations affect uptake by DCs and DC function. Here, we examined monocyte-derived DC (moDC) and skin DC uptake of six different liposomal formulations, together with their DC-modulating effect. Contrary to literature, we show using imaging flow cytometry that anionic or neutral liposomes are taken up more efficiently than cationic liposomes by moDCs, or by skin DCs after intradermal injection. None of the formulations yielded significant modulation of DC function as determined by the upregulation of maturation markers and cytokine production. These results suggest that anionic liposomes would be more suitable as vaccine carriers for a dermal application.


Assuntos
Células Dendríticas , Lipossomos , Fatores Imunológicos , Imunoterapia/métodos , Cinética
3.
Front Immunol ; 12: 643240, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679806

RESUMO

Dendritic cells (DCs) are well-established as major players in the regulation of immune responses. They either induce inflammatory or tolerogenic responses, depending on the DC-subtype and stimuli they receive from the local environment. This dual capacity of DCs has raised therapeutic interest for their use to modify immune-activation via the generation of tolerogenic DCs (tolDCs). Several compounds such as vitamin D3, retinoic acid, dexamethasone, or IL-10 and TGF-ß have shown potency in the induction of tolDCs. However, an increasing interest exists in defining tolerance inducing receptors on DCs for new targeting strategies aimed to develop tolerance inducing immunotherapies, on which we focus particular in this review. Ligation of specific cell surface molecules on DCs can result in antigen presentation to T cells in the presence of inhibitory costimulatory molecules and tolerogenic cytokines, giving rise to regulatory T cells. The combination of factors such as antigen structure and conformation, delivery method, and receptor specificity is of paramount importance. During the last decades, research provided many tools that can specifically target various receptors on DCs to induce a tolerogenic phenotype. Based on advances in the knowledge of pathogen recognition receptor expression profiles in human DC subsets, the most promising cell surface receptors that are currently being explored as possible targets for the induction of tolerance in DCs will be discussed. We also review the different strategies that are being tested to target DC receptors such as antigen-carbohydrate conjugates, antibody-antigen fusion proteins and antigen-adjuvant conjugates.


Assuntos
Apresentação de Antígeno , Células Dendríticas/imunologia , Tolerância Imunológica , Imunoterapia , Receptores de Superfície Celular/imunologia , Linfócitos T Reguladores/imunologia , Humanos , Interleucina-10/imunologia , Fator de Crescimento Transformador beta/imunologia
4.
FASEB J ; 34(5): 6382-6398, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32159259

RESUMO

Tubular ATP release is regulated by mechanosensation of fluid shear stress (FSS). Polycystin-1/polycystin-2 (PC1/PC2) functions as a mechanosensory complex in the kidney. Extracellular ATP is implicated in polycystic kidney disease (PKD), where PC1/PC2 is dysfunctional. This study aims to provide new insights into the ATP signaling under physiological conditions and PKD. Microfluidics, pharmacologic inhibition, and loss-of-function approaches were combined to assess the ATP release in mouse distal convoluted tubule 15 (mDCT15) cells. Kidney-specific Pkd1 knockout mice (iKsp-Pkd1-/- ) and zebrafish pkd2 morphants (pkd2-MO) were as models for PKD. FSS-exposed mDCT15 cells displayed increased ATP release. Pannexin-1 inhibition and knockout decreased FSS-modulated ATP release. In iKsp-Pkd1-/- mice, elevated renal pannexin-1 mRNA expression and urinary ATP were observed. In Pkd1-/- mDCT15 cells, elevated ATP release was observed upon the FSS mechanosensation. In these cells, increased pannexin-1 mRNA expression was observed. Importantly, pannexin-1 inhibition in pkd2-MO decreased the renal cyst growth. Our results demonstrate that pannexin-1 channels mediate ATP release into the tubular lumen due to pro-urinary flow. We present pannexin-1 as novel therapeutic target to prevent the renal cyst growth in PKD.


Assuntos
Trifosfato de Adenosina/urina , Conexinas/metabolismo , Cistos/patologia , Proteínas do Tecido Nervoso/metabolismo , Doenças Renais Policísticas/patologia , Estresse Mecânico , Canais de Cátion TRPP/fisiologia , Adulto , Animais , Cálcio/metabolismo , Conexinas/genética , Cistos/genética , Cistos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Doenças Renais Policísticas/genética , Doenças Renais Policísticas/metabolismo , Peixe-Zebra
5.
Nat Rev Nephrol ; 16(6): 337-351, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32127698

RESUMO

The kidney is a remarkable organ that accomplishes the challenge of removing waste from the body and simultaneously regulating electrolyte and water balance. Pro-urine flows through the nephron in a highly dynamic manner and adjustment of the reabsorption rates of water and ions to the variable tubular flow is required for electrolyte homeostasis. Renal epithelial cells sense the tubular flow by mechanosensation. Interest in this phenomenon has increased in the past decade since the acknowledgement of primary cilia as antennae that sense renal tubular flow. However, the significance of tubular flow sensing for electrolyte handling is largely unknown. Signal transduction pathways regulating flow-sensitive physiological responses involve calcium, purinergic and nitric oxide signalling, and are considered to have an important role in renal electrolyte handling. Given that mechanosensation of tubular flow is an integral role of the nephron, defective tubular flow sensing is probably involved in renal disease. Studies investigating tubular flow and electrolyte transport differ in their methodology, subsequently hampering translational validity. This Review provides the basis for understanding electrolyte disorders originating from altered tubular flow sensing as a result of pathological conditions.


Assuntos
Sinalização do Cálcio/fisiologia , Túbulos Renais/metabolismo , Óxido Nítrico/metabolismo , Receptores Purinérgicos/metabolismo , Reabsorção Renal/fisiologia , Equilíbrio Hidroeletrolítico/fisiologia , Desequilíbrio Hidroeletrolítico/metabolismo , Água Corporal/metabolismo , Cílios , Eletrólitos/metabolismo , Células Epiteliais , Taxa de Filtração Glomerular , Humanos , Pelve Renal , Mecanotransdução Celular , Microfluídica , Transdução de Sinais
6.
PLoS One ; 13(7): e0200316, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29985950

RESUMO

Polycomb Group (PcG) genes are transcriptional repressors that are described to be important during development and differentiation. There is significant interest in PcGs proteins because of their role in stem cell biology and tumorigenesis. In this study we characterize the expression of a selection of PcG genes in the adult germline of zebrafish and during embryogenesis. In adults, expression of selected PcG genes is found to be enriched in germ line over somatic tissues. Therefore, the germ line of adult zebrafish was analyzed for the expression pattern of a selection of PcG genes by whole mount in situ hybridization. We detected presence of the tested PcG gene transcripts at early stages of both oogenesis and spermatogenesis. This enriched expression for early stages of gametogenesis is also observed in developing gonads at 4 and 5 weeks post fertilization. Additionally, zebrafish embryos were used to study the spatio-temporal expression patterns of a selection of PcG genes during development. The PcG genes that we tested are maternally loaded and ubiquitously expressed at early developmental stages, except of ezh1. The expression of the PcG genes that were assessed becomes enriched anteriorly and is more defined during tissue specification. The data shown here is an important resource for functional PcG gene studies in vivo.


Assuntos
Diferenciação Celular/genética , Desenvolvimento Embrionário/genética , Regulação da Expressão Gênica no Desenvolvimento , Proteínas do Grupo Polycomb/genética , Transcriptoma , Peixe-Zebra/genética , Animais , Embrião não Mamífero , Perfilação da Expressão Gênica , Células Germinativas , Peixe-Zebra/embriologia
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