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1.
J Immunol ; 212(11): 1843-1854, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38568091

RESUMO

Intraepithelial lymphocytes (IELs) are T cells important for the maintenance of barrier integrity in the intestine. Colon IELs are significantly reduced in both MyD88-deficient mice and those lacking an intact microbiota, suggesting that MyD88-mediated detection of bacterial products is important for the recruitment and/or retention of these cells. Here, using conditionally deficient MyD88 mice, we show that myeloid cells are the key mediators of TCRαß+ IEL recruitment to the colon. Upon exposure to luminal bacteria, myeloid cells produce sphingosine-1-phosphate (S1P) in a MyD88-dependent fashion. TCRαß+ IEL recruitment may be blocked using the S1P receptor antagonist FTY720, confirming the importance of S1P in the recruitment of TCRαß+ IELs to the colon epithelium. Finally, using the TNFΔARE/+ model of Crohn's-like bowel inflammation, we show that disruption of colon IEL recruitment through myeloid-specific MyD88 deficiency results in reduced pathology. Our results illustrate one mechanism for recruitment of a subset of IELs to the colon.


Assuntos
Colo , Mucosa Intestinal , Linfócitos Intraepiteliais , Lisofosfolipídeos , Camundongos Knockout , Células Mieloides , Fator 88 de Diferenciação Mieloide , Receptores de Antígenos de Linfócitos T alfa-beta , Esfingosina , Animais , Lisofosfolipídeos/metabolismo , Camundongos , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Colo/imunologia , Fator 88 de Diferenciação Mieloide/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Linfócitos Intraepiteliais/imunologia , Linfócitos Intraepiteliais/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Camundongos Endogâmicos C57BL , Cloridrato de Fingolimode/farmacologia , Doença de Crohn/imunologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-28935164

RESUMO

Molting is induced in decapod crustaceans via multiple leg autotomy (MLA) or eyestalk ablation (ESA). MLA removes five or more walking legs, which are regenerated and become functional appendages at ecdysis. ESA eliminates the primary source of molt-inhibiting hormone (MIH) and crustacean hyperglycemic hormone (CHH), which suppress the production of molting hormones (ecdysteroids) from the molting gland or Y-organ (YO). Both MLA and ESA are effective methods for molt induction in Gecarcinus lateralis. However, some G. lateralis individuals are refractory to MLA, as they fail to complete ecdysis by 12weeks post-MLA; these animals are in the "blocked" condition. Quantitative polymerase chain reaction was used to quantify mRNA levels of neuropeptide and mechanistic target of rapamycin (mTOR) signaling genes in YO, eyestalk ganglia (ESG), thoracic ganglion (TG), and brain of intact and blocked animals. Six of the seven neuropeptide signaling genes, three of four mTOR signaling genes, and Gl-elongation factor 2 (EF2) mRNA levels were significantly higher in the ESG of blocked animals. Gl-MIH and Gl-CHH mRNA levels were higher in the TG and brain of blocked animals and levels increased in both control and blocked animals in response to ESA. By contrast, mRNA levels of Gl-EF2 and five of the 10 MIH signaling pathway genes in the YO were two to four orders of magnitude higher in blocked animals compared to controls. These data suggest that increased MIH and CHH synthesis in the ESG contributes to the prevention of molt induction by MLA in blocked animals. The up-regulation of MIH signaling genes in the YO of blocked animals suggests that the YO is more sensitive to MIH produced in the ESG, as well as MIH produced in brain and TG of ESA animals. Both the up-regulation of MIH signaling genes in the YO and of Gl-MIH and Gl-CHH in the ESG, TG, and brain appear to contribute to some G. lateralis individuals being refractory to MLA and ESA.


Assuntos
Proteínas de Artrópodes/metabolismo , Braquiúros/fisiologia , Glândulas Exócrinas/inervação , Gânglios dos Invertebrados/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hormônios de Invertebrado/metabolismo , Modelos Neurológicos , Proteínas do Tecido Nervoso/metabolismo , Animais , Proteínas de Artrópodes/genética , Oceano Atlântico , Braquiúros/crescimento & desenvolvimento , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , República Dominicana , Ecdisteroides/biossíntese , Ecdisteroides/metabolismo , Glândulas Exócrinas/crescimento & desenvolvimento , Glândulas Exócrinas/metabolismo , Olho/crescimento & desenvolvimento , Olho/inervação , Olho/metabolismo , Gânglios dos Invertebrados/crescimento & desenvolvimento , Hormônios de Invertebrado/genética , Masculino , Muda , Proteínas do Tecido Nervoso/genética , Especificidade de Órgãos , Fatores de Alongamento de Peptídeos/genética , Fatores de Alongamento de Peptídeos/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Cavidade Torácica/crescimento & desenvolvimento , Cavidade Torácica/inervação , Cavidade Torácica/metabolismo
3.
bioRxiv ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37066413

RESUMO

Although river ecosystems comprise less than 1% of Earth's total non-glaciated area, they are critical modulators of microbially and virally orchestrated global biogeochemical cycles. However, most studies either use data that is not spatially resolved or is collected at timepoints that do not reflect the short life cycles of microorganisms. As a result, the relevance of microbiome interactions and the impacts they have over time on biogeochemical cycles are poorly understood. To assess how viral and microbial communities change over time, we sampled surface water and pore water compartments of the wastewater-impacted River Erpe in Germany every 3 hours over a 48-hour period resulting in 32 metagenomes paired to geochemical and metabolite measurements. We reconstructed 6,500 viral and 1,033 microbial genomes and found distinct communities associated with each river compartment. We show that 17% of our vMAGs clustered to viruses from other ecosystems like wastewater treatment plants and rivers. Our results also indicated that 70% of the viral community was persistent in surface waters, whereas only 13% were persistent in the pore waters taken from the hyporheic zone. Finally, we predicted linkages between 73 viral genomes and 38 microbial genomes. These putatively linked hosts included members of the Competibacteraceae, which we suggest are potential contributors to carbon and nitrogen cycling. Together, these findings demonstrate that microbial and viral communities in surface waters of this urban river can exist as stable communities along a flowing river; and raise important considerations for ecosystem models attempting to constrain dynamics of river biogeochemical cycles.

4.
Water Res ; 224: 119056, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-36126632

RESUMO

The hyporheic zone (HZ) is considered a hydrodynamically-driven bioreactor with significant pollutant removal capacities and can therefore not only improve wholestream water quality but also preserve human and ecosystem health. Microbial metabolism is hypothesized to play a key role in pollutant transformation in hyporheic sediments of natural streams. However, previous work investigating the influence of microbial metabolism on pollutant transformation has been predominantly laboratory studies. The key challenge for field studies is the appropriate determination of net microbial metabolism, i.e. information on the actual exposure times to specific microbial processes in the investigated system. The present study uses reactive fluorescent tracers to determine microbial metabolism and ultimately its influence on pollutant transformation, e.g. for trace organic compounds, in hyporheic sediments under natural conditions. In particular, the reactive fluorescent tracers resazurin and its main transformation product resorufin were used to determine the microbial metabolism of facultative or obligate aerobes. The influence of the derived microbial metabolism on the transformation of 20 trace organic compounds, such as pharmaceuticals, including 3 parent-daughter pairs, was examined. The present findings validate laboratory results on the microbially-mediated transformation of the anticonvulsant gabapentin to its main transformation product gabapentin lactam under natural conditions. All other TrOCs investigated did not show a clear link between TrOC reactivity to the microbial metabolism informed by the resazurin-resorufin-system. Overall, the present study not only demonstrates the use of the fluorescent tracer-system resazurin and resorufin for determining microbial metabolism of facultative or obligate aerobes but also generally highlights the potential of reactive fluorescent tracers to disentangle specific reactive properties and ultimately their influence on the fate of pollutants in natural HZs.


Assuntos
Ecossistema , Poluentes Ambientais , Anticonvulsivantes , Bactérias Aeróbias , Gabapentina , Humanos , Lactamas , Compostos Orgânicos , Preparações Farmacêuticas , Rios
5.
J Med Chem ; 65(5): 3798-3813, 2022 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-35229610

RESUMO

A series of 5-aryl-2-amino-imidazothiadiazole (ITD) derivatives were identified by a phenotype-based high-throughput screening using a blood stage Plasmodium falciparum (Pf) growth inhibition assay. A lead optimization program focused on improving antiplasmodium potency, selectivity against human kinases, and absorption, distribution, metabolism, excretion, and toxicity properties and extended pharmacological profiles culminated in the identification of INE963 (1), which demonstrates potent cellular activity against Pf 3D7 (EC50 = 0.006 µM) and achieves "artemisinin-like" kill kinetics in vitro with a parasite clearance time of <24 h. A single dose of 30 mg/kg is fully curative in the Pf-humanized severe combined immunodeficient mouse model. INE963 (1) also exhibits a high barrier to resistance in drug selection studies and a long half-life (T1/2) across species. These properties suggest the significant potential for INE963 (1) to provide a curative therapy for uncomplicated malaria with short dosing regimens. For these reasons, INE963 (1) was progressed through GLP toxicology studies and is now undergoing Ph1 clinical trials.


Assuntos
Antimaláricos , Antagonistas do Ácido Fólico , Malária Falciparum , Malária , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antagonistas do Ácido Fólico/uso terapêutico , Malária/tratamento farmacológico , Malária Falciparum/tratamento farmacológico , Camundongos , Camundongos SCID , Plasmodium falciparum
6.
Sci Rep ; 11(1): 4179, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33603043

RESUMO

Trace organic compounds (TrOCs) enter rivers with discharge of treated wastewater. These effluents can contain high loads of dissolved organic matter (DOM). In a 48 h field study, we investigated changes in molecular composition of seven DOM compound classes (FTICR-MS) and attenuation of 17 polar TrOCs in a small urban stream receiving treated wastewater. Correlations between TrOCs and DOM were used to identify simultaneous changes in surface water and the hyporheic zone. Changes in TrOC concentrations in surface water ranged between a decrease of 29.2% for methylbenzotriazole and an increase of 152.2% for the transformation product gabapentin-lactam. In the hyporheic zone, only decreasing TrOC concentrations were observed, ranging from 4.9% for primidone to 93.8% for venlafaxine . TrOC attenuation coincided with a decline of molecular diversity of easily biodegradable DOM compound classes while molecular diversity of poorly biodegradable DOM compound classes increased. This concurrence indicates similar or linked attenuation pathways for biodegradable DOM and TrOCs. Strong correlations between TrOCs and DOM compound classes as well as high attenuation of TrOCs primarily occurred in the hyporheic zone. This suggests high potential for DOM turnover and TrOC mitigation in rivers if hyporheic exchange is sufficient.

8.
Oncotarget ; 10(60): 6494-6508, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31741713

RESUMO

INTRODUCTION: Mammography is the gold standard for early breast cancer detection, but shows important limitations. Blood-based approaches on basis of cell-free DNA (cfDNA) provide minimally invasive screening tools to characterize epigenetic alterations of tumor suppressor genes and could serve as a liquid biopsy, complementing mammography. METHODS: Potential biomarkers were identified from The Cancer Genome Atlas (TCGA), using HumanMethylation450-BeadChip data. Promoter methylation status was evaluated quantitatively by pyrosequencing in a serum test cohort (n = 103), a serum validation cohort (n = 368) and a plasma cohort (n = 125). RESULTS: SPAG6, NKX2-6 and PER1 were identified as novel biomarker candidates. ITIH5 was included on basis of our previous work. In the serum test cohort, a panel of SPAG6 and ITIH5 showed 63% sensitivity for DCIS and 51% sensitivity for early invasive tumor (pT1, pN0) detection at 80% specificity. The serum validation cohort revealed 50% sensitivity for DCIS detection on basis of NKX2-6 and ITIH5. Furthermore, an inverse correlation between methylation frequency and cfDNA concentration was uncovered. Therefore, markers were tested in a plasma cohort, achieving a 64% sensitivity for breast cancer detection using SPAG6, PER1 and ITIH5. CONCLUSIONS: Although liquid biopsy remains challenging, a combination of SPAG6, NKX2-6, ITIH5 and PER1 (SNiPER) provides a promising tool for blood-based breast cancer detection.

9.
Arthritis Rheumatol ; 70(8): 1220-1233, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29534332

RESUMO

OBJECTIVE: Observations of microbial dysbiosis in patients with rheumatoid arthritis (RA) have raised interest in studying microbial-mucosal interactions as a potential trigger of RA. Using the murine collagen-induced arthritis (CIA) model, we undertook this study to test our hypothesis that microbiota modulate immune responses leading to autoimmune arthritis. METHODS: CIA was induced by immunization of mice with type II collagen (CII) in adjuvant on days 0 and 21, with arthritis appearing on days 23 and 24. Intestinal microbiota were profiled by 16S ribosomal RNA sequencing every 7 days during the course of CIA, and intestinal mucosal changes were evaluated on days 14 and 35. Then, microbiota were depleted either early (7 days before immunization) or late (day 21 after immunization) by administration of broad-spectrum antibiotics. Disease severity, autoantibody and systemic cytokine production, and intestinal mucosal responses were monitored in the setting of microbial reduction. RESULTS: Significant dysbiosis and mucosal inflammation occurred early in CIA, prior to visible arthritis, and continued to evolve during the course of disease. Depletion of the microbiota prior to the induction of CIA resulted in an ~40% reduction in disease severity and in significantly reduced levels of serum inflammatory cytokines and anti-CII antibodies. In intestinal tissue, production of interleukin-17A (IL-17A) and IL-22 was delayed. Unexpectedly, microbial depletion during the late phase of CIA resulted in a >50% decrease in disease severity. Anti-CII antibodies were mildly reduced but were significantly impaired in their ability to activate complement, likely due to altered glycosylation profiles. CONCLUSION: These data support a model in which intestinal dysbiosis triggers mucosal immune responses that stimulate T and B cells that are key for the development of inflammatory arthritis.


Assuntos
Artrite Experimental/microbiologia , Artrite Reumatoide/microbiologia , Autoanticorpos/sangue , Microbioma Gastrointestinal/imunologia , Mucosa Intestinal/imunologia , Animais , Artrite Experimental/imunologia , Artrite Reumatoide/imunologia , Autoanticorpos/imunologia , Colágeno Tipo II/imunologia , Citocinas/sangue , Citocinas/imunologia , Modelos Animais de Doenças , Imunidade nas Mucosas/genética , Imunidade nas Mucosas/imunologia , Mucosa Intestinal/microbiologia , Camundongos , RNA Ribossômico 16S/metabolismo
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