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1.
medRxiv ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38746201

RESUMO

Context: Thyroid eye disease (TED) is an autoimmune disease characterized by orbital inflammation and tissue remodeling. TED pathogenesis is poorly understood but is linked to autoantibodies to thyroid-stimulating hormone receptor (TSHR) and insulin-like growth factor 1 receptor (IGF-1R). Objective: To explore the potential involvement of viral infections in TED pathogenesis. Methods: Using NCBI BLAST, we compared human TSHR and IGF-1R proteins to various viral proteomes, including Papillomaviridae , Paramyxoviridae , Herpesviridae , Enterovirus , Polyomaviridae , and Rhabdoviridae . Enzyme-linked immunoassays (ELISAs) were performed on orbital adipose tissue samples from 22 TED patients and controls to quantify antiviral antibody titers. Demographics and clinical data were reviewed. Results: Homology analysis revealed conserved motifs between TSHR and IGF-1R with several viral proteins, particularly the human papillomavirus 18 (HPV18) L1 capsid protein. Basic demographic and clinical information between the cohorts were comparable. ELISAs showed statistically significant differences in the average HPV18 L1 IgG normalized optical density levels among tissues of control ( M = 0.9387, SD = 0.3548), chronic TED ( M = 2.305, SD = 1.064), and active acute TED ( M = 4.087, SD = 2.034) patients. These elevated HPV18 L1 IgG titers did not statistically correlate with TSH, T4, or TSI levels, and were elevated in TED patients irrespective of treatment with teprotumumab, indicating a direct immunological response to HPV. Conclusions: This study presents the first molecular evidence linking HPV and TED, highlighting molecular mimicry between HPV capsid protein and key autoimmunity targets in TED. This suggests an immunological link contributing to TED's pathogenesis, opening new avenues for understanding and managing the disease.

2.
Ophthalmic Plast Reconstr Surg ; 40(3): e89-e91, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38738721

RESUMO

A 40-year-old woman underwent periocular plasma skin regeneration, a cosmetic treatment for periorbital rejuvenation. She subsequently developed bilateral thermal keratitis, manifesting as blurred vision, irritation, and redness, with a vision decrease to 20/60 and 20/50 in her OD and OS, respectively. Examination demonstrated bilateral large, irregular corneal epithelial defects and edema, necessitating treatment with amniotic membrane grafts, bandage contact lenses, and hypertonic saline. One year posttreatment, her visual acuity improved to 20/20 and 20/25, albeit with ongoing symptomatic dryness and bilateral anterior stromal haze. This case, as only the second reported instance of ocular damage from periocular plasma skin regeneration, underscores the need for heightened awareness of potential ocular complications following plasma skin regeneration and reinforces the importance of protective measures during periocular procedures.


Assuntos
Queimaduras Oculares , Humanos , Feminino , Adulto , Queimaduras Oculares/induzido quimicamente , Queimaduras Oculares/diagnóstico , Ceratite/diagnóstico , Ceratite/etiologia , Ceratite/fisiopatologia , Gases em Plasma/uso terapêutico , Regeneração/fisiologia , Técnicas Cosméticas/efeitos adversos , Acuidade Visual
3.
Sci Transl Med ; 16(747): eadl1722, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748773

RESUMO

The evolution of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) requires ongoing monitoring to judge the ability of newly arising variants to escape the immune response. A surveillance system necessitates an understanding of differences in neutralization titers measured in different assays and using human and animal serum samples. We compared 18 datasets generated using human, hamster, and mouse serum and six different neutralization assays. Datasets using animal model serum samples showed higher titer magnitudes than datasets using human serum samples in this comparison. Fold change in neutralization of variants compared to ancestral SARS-CoV-2, immunodominance patterns, and antigenic maps were similar among serum samples and assays. Most assays yielded consistent results, except for differences in fold change in cytopathic effect assays. Hamster serum samples were a consistent surrogate for human first-infection serum samples. These results inform the transition of surveillance of SARS-CoV-2 antigenic variation from dependence on human first-infection serum samples to the utilization of serum samples from animal models.


Assuntos
Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19 , Testes de Neutralização , SARS-CoV-2 , Animais , Humanos , SARS-CoV-2/imunologia , COVID-19/imunologia , COVID-19/sangue , COVID-19/virologia , Camundongos , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Cricetinae , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Modelos Animais de Doenças
4.
Nat Commun ; 15(1): 2699, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38538636

RESUMO

Even after successful extinction, conditioned fear can return. Strengthening the consolidation of the fear-inhibitory safety memory formed during extinction is one way to counteract return of fear. In a previous study, we found that post-extinction L-DOPA administration improved extinction memory retrieval 24 h later. Furthermore, spontaneous post-extinction reactivations of a neural activation pattern evoked in the ventromedial prefrontal cortex (vmPFC) during extinction predicted extinction memory retrieval, L-DOPA increased the number of these reactivations, and this mediated the effect of L-DOPA on extinction memory retrieval. Here, we conducted a preregistered replication study of this work in healthy male participants. We confirm that spontaneous post-extinction vmPFC reactivations predict extinction memory retrieval. This predictive effect, however, was only observed 90 min after extinction, and was not statistically significant at 45 min as in the discovery study. In contrast to our previous study, we find no evidence that L-DOPA administration significantly enhances retrieval and that this is mediated by enhancement of the number of vmPFC reactivations. However, additional non-preregistered analyses reveal a beneficial effect of L-DOPA on extinction retrieval when controlling for the trait-like stable baseline levels of salivary alpha-amylase enzymatic activity. Further, trait salivary alpha-amylase negatively predicts retrieval, and this effect is reduced by L-DOPA treatment. Importantly, the latter findings result from non-preregistered analyses and thus further investigation is needed.


Assuntos
Dopamina , alfa-Amilases Salivares , Humanos , Masculino , Dopamina/farmacologia , Levodopa/farmacologia , alfa-Amilases Salivares/farmacologia , Extinção Psicológica/fisiologia , Memória , Córtex Pré-Frontal/fisiologia
5.
Carbon Balance Manag ; 19(1): 10, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38430356

RESUMO

BACKGROUND: Forests mitigate climate change by reducing atmospheric CO 2 -concentrations through the carbon sink in the forest and in wood products, and substitution effects when wood products replace carbon-intensive materials and fuels. Quantifying the carbon mitigation potential of forests is highly challenging due to the influence of multiple important factors such as forest age and type, climate change and associated natural disturbances, harvest intensities, wood usage patterns, salvage logging practices, and the carbon-intensity of substituted products. Here, we developed a framework to quantify the impact of these factors through factorial simulation experiments with an ecosystem model at the example of central European (Bavarian) forests. RESULTS: Our simulations showed higher mitigation potentials of young forests compared to mature forests, and similar ones in broad-leaved and needle-leaved forests. Long-lived wood products significantly contributed to mitigation, particularly in needle-leaved forests due to their wood product portfolio, and increased material usage of wood showed considerable climate benefits. Consequently, the ongoing conversion of needle-leaved to more broad-leaved forests should be accompanied by the promotion of long-lived products from broad-leaved species to maintain the product sink. Climate change (especially increasing disturbances) and decarbonization were among the most critical factors influencing mitigation potentials and introduced substantial uncertainty. Nevertheless, until 2050 this uncertainty was narrow enough to derive robust findings. For instance, reducing harvest intensities enhanced the carbon sink in our simulations, but diminished substitution effects, leading to a decreased total mitigation potential until 2050. However, when considering longer time horizons (i.e. until 2100), substitution effects became low enough in our simulations due to expected decarbonization such that decreasing harvests often seemed the more favorable solution. CONCLUSION: Our results underscore the need to tailor mitigation strategies to the specific conditions of different forest sites. Furthermore, considering substitution effects, and thoroughly assessing the amount of avoided emissions by using wood products, is critical to determine mitigation potentials. While short-term recommendations are possible, we suggest risk diversification and methodologies like robust optimization to address increasing uncertainties from climate change and decarbonization paces past 2050. Finally, curbing emissions reduces the threat of climate change on forests, safeguarding their carbon sink and ecosystem services.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38372611

RESUMO

PURPOSE: This study aims to address the infrequent but serious complication of globe injuries in blepharoplasty. METHODS: A case series of 3 patients with globe injuries postblepharoplasty is presented, along with a systematic literature review that revealed 13 previously reported cases. Quantitative and comparative analysis is described. RESULTS: Injuries ranged from deep thermal burns to full-thickness corneal or scleral lacerations, with one instance of traumatic cataract. The median time from surgery to symptom onset was 1 day, with a concerning median delay of 7 days to presentation to an ophthalmologist. Visual outcomes were generally poor, with nearly all patients experiencing permanent visual morbidity. The systematic review revealed 3 cases of endophthalmitis following perforating scleral injuries. Comparative analysis showed no significant differences in visual outcomes between penetrating and perforating injuries. CONCLUSIONS: The findings of this study emphasize the need for increased vigilance for globe injuries that require prompt ophthalmological evaluation following blepharoplasty, especially considering the observed delay in presentation and the extent of visual morbidity. The study advocates for improved practitioner training in recognizing and managing these complications and underscores the importance of patient education regarding the potential risks and the necessity of timely postoperative care.

9.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 777-788, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37878037

RESUMO

PURPOSE: To evaluate the clinical characteristics of congenital rubella retinopathy (CRR) with modern fundus imaging. METHODS: Single-center case series. Eleven patients (2005-2020) at the Emory Eye Center with known or presumed CRR. Trained image readers reviewed fundus imaging (color fundus photography, widefield pseudocolor imaging, near-infrared reflectance imaging, autofluorescence imaging, and spectral-domain optical coherence tomography) for pre-specified features suggestive of CRR. RESULTS: Eleven patients with confirmed (63.6%) or presumed (36.3%) CRR were identified. All were female with median (range) age of 53 (35-67) years. Six (54.5%) were born during the 1964-1965 United States rubella epidemic. All had congenital hearing loss. Two (18.2%) had a congenital heart defect. Eleven (50.0%) eyes had salt-and-pepper retinal pigmentary changes. Twenty-two eyes (100.0%) had irregularly distributed regions of speckled hypoautofluorescence. One eye (4.5%) had a presumed macular neovascularization. CONCLUSION: Modern fundus imaging demonstrates characteristic features of CRR, even when pigmentary changes are not readily apparent on examination. Widefield autofluorescence findings of irregularly distributed speckled hypoautofluorescence are particularly revealing. This series of newly diagnosed adults with CRR may represent the milder end of the phenotypic spectrum of this condition, highlighting imaging findings that may aid in diagnostically challenging cases of CRR.


Assuntos
Infecções Oculares Virais , Doenças Retinianas , Retinite , Síndrome da Rubéola Congênita , Rubéola (Sarampo Alemão) , Adulto , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Doenças Retinianas/diagnóstico , Síndrome da Rubéola Congênita/diagnóstico , Fundo de Olho , Rubéola (Sarampo Alemão)/diagnóstico
10.
EBioMedicine ; 98: 104893, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38035462

RESUMO

BACKGROUND: Mucosal antibodies play a key role in the protection against SARS-CoV-2 infection in the upper respiratory tract, and potentially in limiting virus replication and therefore onward transmission. While systemic immunity to SARS-CoV-2 is well understood, we have a limited understanding about the antibodies present on the nasal mucosal surfaces. METHODS: In this study, we evaluated SARS-CoV-2 mucosal antibodies following previous infection, vaccination, or a combination of both. Paired nasal fluid and serum samples were collected from 143 individuals, which include convalescent, vaccinated, or breakthrough infections. FINDINGS: We detected a high correlation between IgG responses in serum and nasal fluids, which were higher in both compartments in vaccinated compared to convalescent participants. Contrary, nasal and systemic SARS-CoV-2 IgA responses were weakly correlated, indicating a compartmentalization between the local and systemic IgA responses. SARS-CoV-2 secretory component IgA (s-IgA) antibodies, present exclusively on mucosal surfaces, were detected in the nasal fluid only in a minority of vaccinated subjects and were significantly higher in previously infected individuals. Depletion of IgA antibodies in nasal fluids resulted in a tremendous reduction of neutralization activity against SARS-CoV-2, indicating that IgA is the crucial contributor to neutralization in the nasal mucosa. Neutralization against SARS-CoV-2 was higher in the mucosa of subjects with previous SARS-CoV-2 infections compared to vaccinated participants. INTERPRETATION: In summary, we demonstrate that currently available vaccines elicit strong systemic antibody responses, but SARS-CoV-2 infection generates higher titers of binding and neutralizing mucosal antibodies. Our results support the importance to develop SARS-CoV-2 vaccines that elicit mucosal antibodies. FUNDING: The work was funded by the COVID-19 National Research Program 78 (grant number 198412) of the Swiss National Science Foundation.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Imunidade nas Mucosas , Vacinas contra COVID-19 , Convalescença , Imunoglobulina A Secretora , Anticorpos Neutralizantes , Anticorpos Antivirais , Imunidade Adaptativa , Imunoglobulina A
11.
Mol Biotechnol ; 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37782430

RESUMO

Hepatocellular carcinoma (HCC) is the primary malignancy of hepatocytes and the second most common cause of cancer-related mortality across the globe. Despite significant advancements in screening, diagnosis, and treatment modalities for HCC, the mortality-to-incidence ratio remain unacceptably high. A recent study indicates that a minor population of HCCs are AFP negative or express the normal range of AFP levels. Although it is a gold standard and a more reliable biomarker in the advanced stage of HCC and poorly differentiated tumors, it does not serve as a suitable means for screening HCC. AFP plays a significant role in the development and progression of HCC and understanding its role is crucial. By examining the molecular mechanisms involved in AFP-mediated tumorigenesis, we can better understand HCC pathogenesis and identify potential therapeutic targets. This article details the role of alpha-fetoprotein (AFP) in the carcinogenic transformation of hepatocytes. The article also focuses on information about the structure, biosynthesis, and regulation of AFP at the gene level. Additionally, it discusses the immune evasion, metastasis, and control of gene expression that AFP mediates during HCC.

12.
bioRxiv ; 2023 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-37808679

RESUMO

The antigenic evolution of SARS-CoV-2 requires ongoing monitoring to judge the immune escape of newly arising variants. A surveillance system necessitates an understanding of differences in neutralization titers measured in different assays and using human and animal sera. We compared 18 datasets generated using human, hamster, and mouse sera, and six different neutralization assays. Titer magnitude was lowest in human, intermediate in hamster, and highest in mouse sera. Fold change, immunodominance patterns and antigenic maps were similar among sera. Most assays yielded similar results, except for differences in fold change in cytopathic effect assays. Not enough data was available for conclusively judging mouse sera, but hamster sera were a consistent surrogate for human first-infection sera.

13.
Front Immunol ; 14: 1107156, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37006315

RESUMO

Objectives: To comprehensively analyze the quality of the antibody response between children with Multisystem inflammatory syndrome (MIS-C) and age-matched controls at one month after SARS-CoV-2 exposure, and infected in the same time-period. Methods: Serum from 20 MIS-C children at admission, and 14 control children were analyzed. Antigen specific antibody isotypes and subclasses directed against various antigens of SARS-CoV-2 as well as against human common coronavirus (HCoVs) and commensal or pathogenic microorganisms were assessed by a bead-based multiplexed serological assay and by ELISA. The functionality of these antibodies was also assessed using a plaque reduction neutralization test, a RBD-specific avidity assay, a complement deposition assay and an antibody-dependent neutrophil phagocytosis (ADNP) assay. Results: Children with MIS-C developed a stronger IgA antibody response in comparison to children with uncomplicated COVID-19, while IgG and IgM responses are largely similar in both groups. We found a typical class-switched antibody profile with high level of IgG and IgA titers and a measurable low IgM due to relatively recent SARS-CoV-2 infection (one month). SARS-CoV-2-specific IgG antibodies of MIS-C children had higher functional properties (higher neutralization activity, avidity and complement binding) as compared to children with uncomplicated COVID-19. There was no difference in the response to common endemic coronaviruses between both groups. However, MIS-C children had a moderate increase against mucosal commensal and pathogenic strains, reflecting a potential association between a disruption of the mucosal barrier with the disease. Conclusion: Even if it is still unclear why some children develop a MIS-C, we show here that MIS-C children produce higher titers of IgA antibodies, and IgG antibodies with higher functionality, which could reflect the local gastro-intestinal mucosal inflammation potentially induced by a sustained SARS-CoV-2 gut infection leading to continuous release of SARS-CoV-2 antigens.


Assuntos
Antígenos de Grupos Sanguíneos , COVID-19 , Doenças do Tecido Conjuntivo , Humanos , Criança , SARS-CoV-2 , Formação de Anticorpos , Anticorpos Antivirais , Imunoglobulina A , Imunoglobulina G , Imunoglobulina M
14.
medRxiv ; 2023 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-37066211

RESUMO

Introduction: We describe a novel colopathy associated with pentosan polysulfate (PPS) use and measure the strength of the drug-disease association. Methods: Two-part investigation. In the cohort study of individuals with a history of prior long-term PPS use, case histories were obtained and gastrointestinal disease course was followed with review of endoscopy records and histopathology specimens. Findings were summarized with descriptive statistics. In the cross-sectional study of individuals with interstitial cystitis, drug exposure and medical histories were obtained for patients seen at a single clinical center. Strength of association between PPS use and diagnoses of inflammatory bowel disease (IBD) and/or irritable bowel syndrome (IBS) was measured with multivariate logistic regression. Results: In the cohort study of 13 participants, median PPS exposure was 2.04 kg (0.99-2.54). Eleven (84.6%) developed symptoms suggestive of IBD and/or IBS after initiation of PPS therapy. Of the 10 participants whose endoscopic and histopathologic findings we reviewed, six had abnormal-appearing colonic mucosa on endoscopy and all 10 had abnormal mucosal changes on histology. Clinical and histologic improvement was observed after PPS cessation. In the cross-sectional study of 219 subjects with interstitial cystitis, PPS use was a statistically significant predictor of both the IBD [adjusted odds ratio=3.3 (95% confidence interval, 1.2-8.8, p=0.02)] and the composite IBD+IBS [adjusted odds ratio=3.3 (95% confidence interval, 1.5-7.3, p=0.002)] outcomes. Discussion: We describe a strong association between PPS use and a clinical diagnosis of IBD and/or IBS. Histopathologic findings suggest a novel drug-associated colopathy, with some subjects requiring colectomy for dysplasia.

15.
Brain Commun ; 5(2): fcad035, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36895959

RESUMO

Physiological responses to threat and stress stimuli entrain synchronized neural oscillations among cerebral networks. Network architecture and adaptation may play a critical role in achieving optimal physiological responses, while alteration can lead to mental dysfunction. We reconstructed cortical and sub-cortical source time series from high-density electroencephalography, which were then fed into community architecture analysis. Dynamic alterations were evaluated in terms of flexibility, clustering coefficient and global and local efficiency, as parameters of community allegiance. Transcranial magnetic stimulation was applied over the dorsomedial prefrontal cortex during the time window relevant for physiological threat processing and effective connectivity was computed to test the causality of network dynamics. A theta band-driven community re-organization was evident in key anatomical regions conforming the central executive, salience network and default mode networks during instructed threat processing. Increased network flexibility entrained the physiological responses to threat processing. The effective connectivity analysis showed that information flow differed between theta and alpha bands and were modulated by transcranial magnetic stimulation in salience and default mode networks during threat processing. Theta oscillations drive dynamic community network re-organization during threat processing. Nodal community switches may modulate the directionality of information flow and determine physiological responses relevant to mental health.

17.
PLoS One ; 18(3): e0283149, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36952463

RESUMO

OBJECTIVES: We evaluate the diagnostic performance of dried blood microsampling combined with a high-throughput microfluidic nano-immunoassay (NIA) for the identification of anti-SARS-CoV-2 Spike IgG seropositivity. METHODS: We conducted a serological study among 192 individuals with documented prior SARS-CoV-2 infection and 44 SARS-CoV-2 negative individuals. Participants with prior SARS-CoV-2 infection had a long interval of 11 months since their qRT-PCR positive test. Serum was obtained after venipuncture and tested with an automated electrochemiluminescence anti-SARS-CoV-2 S total Ig reference assay, a commercial ELISA anti-S1 IgG assay, and the index test NIA. In addition, 109 participants from the positive cohort and 44 participants from the negative cohort participated in capillary blood collection using three microsampling devices: Mitra, repurposed glucose test strips, and HemaXis. Samples were dried, shipped by regular mail, extracted, and measured with NIA. RESULTS: Using serum samples, we achieve a clinical sensitivity of 98·33% and specificity of 97·62% on NIA, affirming the high performance of NIA in participants 11 months post infection. Combining microsampling with NIA, we obtain a clinical sensitivity of 95·05% using Mitra, 61·11% using glucose test strips, 83·16% using HemaXis, and 91·49% for HemaXis after automated extraction, without any drop in specificity. DISCUSSION: High sensitivity and specificity was demonstrated when testing micro-volume capillary dried blood samples using NIA, which is expected to facilitate its use in large-scale studies using home-based sampling or samples collected in the field.


Assuntos
COVID-19 , Humanos , Anticorpos Antivirais , COVID-19/diagnóstico , Imunoglobulina G , Microfluídica , SARS-CoV-2 , Sensibilidade e Especificidade
18.
Sci Total Environ ; 872: 162196, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36781140

RESUMO

Our capacity to predict trajectories of ecosystem degradation and recovery is limited, especially when impairments are caused by multiple stressors. Recovery may be fast or slow and either complete or partial, sometimes result in novel ecosystem states or even fail completely. Here, we introduce the Asymmetric Response Concept (ARC) that provides a basis for exploring and predicting the pace and magnitude of ecological responses to, and release from, multiple stressors. The ARC holds that three key mechanisms govern population, community and ecosystem trajectories. Stress tolerance is the main mechanism determining responses to increasing stressor intensity, whereas dispersal and biotic interactions predominantly govern responses to the release from stressors. The shifting importance of these mechanisms creates asymmetries between the ecological trajectories that follow increasing and decreasing stressor intensities. This recognition helps to understand multiple stressor impacts and to predict which measures will restore communities that are resistant to restoration.


Assuntos
Ecossistema , Rios
19.
Int J Mol Sci ; 24(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36835307

RESUMO

Myelodysplastic Syndromes (MDSs) are bone marrow (BM) failure malignancies characterized by constitutive innate immune activation, including NLRP3 inflammasome driven pyroptotic cell death. We recently reported that the danger-associated molecular pattern (DAMP) oxidized mitochondrial DNA (ox-mtDNA) is diagnostically increased in MDS plasma although the functional consequences remain poorly defined. We hypothesized that ox-mtDNA is released into the cytosol, upon NLRP3 inflammasome pyroptotic lysis, where it propagates and further enhances the inflammatory cell death feed-forward loop onto healthy tissues. This activation can be mediated via ox-mtDNA engagement of Toll-like receptor 9 (TLR9), an endosomal DNA sensing pattern recognition receptor known to prime and activate the inflammasome propagating the IFN-induced inflammatory response in neighboring healthy hematopoietic stem and progenitor cells (HSPCs), which presents a potentially targetable axis for the reduction in inflammasome activation in MDS. We found that extracellular ox-mtDNA activates the TLR9-MyD88-inflammasome pathway, demonstrated by increased lysosome formation, IRF7 translocation, and interferon-stimulated gene (ISG) production. Extracellular ox-mtDNA also induces TLR9 redistribution in MDS HSPCs to the cell surface. The effects on NLRP3 inflammasome activation were validated by blocking TLR9 activation via chemical inhibition and CRISPR knockout, demonstrating that TLR9 was necessary for ox-mtDNA-mediated inflammasome activation. Conversely, lentiviral overexpression of TLR9 sensitized cells to ox-mtDNA. Lastly, inhibiting TLR9 restored hematopoietic colony formation in MDS BM. We conclude that MDS HSPCs are primed for inflammasome activation via ox-mtDNA released by pyroptotic cells. Blocking the TLR9/ox-mtDNA axis may prove to be a novel therapeutic strategy for MDS.


Assuntos
DNA Mitocondrial , Inflamassomos , Síndromes Mielodisplásicas , Receptor Toll-Like 9 , Humanos , DNA Mitocondrial/metabolismo , Inflamassomos/metabolismo , Síndromes Mielodisplásicas/genética , Síndromes Mielodisplásicas/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Transdução de Sinais/fisiologia , Receptor Toll-Like 9/metabolismo
20.
Nat Commun ; 14(1): 476, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717561

RESUMO

The adaptive immune response is under circadian control, yet, why adaptive immune reactions continue to exhibit circadian changes over long periods of time is unknown. Using a combination of experimental and mathematical modeling approaches, we show here that dendritic cells migrate from the skin to the draining lymph node in a time-of-day-dependent manner, which provides an enhanced likelihood for functional interactions with T cells. Rhythmic expression of TNF in the draining lymph node enhances BMAL1-controlled ICAM-1 expression in high endothelial venules, resulting in lymphocyte infiltration and lymph node expansion. Lymph node cellularity continues to be different for weeks after the initial time-of-day-dependent challenge, which governs the immune response to vaccinations directed against Hepatitis A virus as well as SARS-CoV-2. In this work, we present a mechanistic understanding of the time-of-day dependent development and maintenance of an adaptive immune response, providing a strategy for using time-of-day to optimize vaccination regimes.


Assuntos
COVID-19 , Relógios Circadianos , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Imunidade Adaptativa , Vacinação , Linfonodos
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