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1.
Proc Natl Acad Sci U S A ; 119(47): e2213879119, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36383746

RESUMO

The main mathematical result in this paper is that change of variables in the ordinary differential equation (ODE) for the competition of two infections in a Susceptible-Infected-Removed (SIR) model shows that the fraction of cases due to the new variant satisfies the logistic differential equation, which models selective sweeps. Fitting the logistic to data from the Global Initiative on Sharing All Influenza Data (GISAID) shows that this correctly predicts the rapid turnover from one dominant variant to another. In addition, our fitting gives sensible estimates of the increase in infectivity. These arguments are applicable to any epidemic modeled by SIR equations.


Assuntos
COVID-19 , Epidemias , Influenza Humana , Humanos , SARS-CoV-2/genética , Suscetibilidade a Doenças
2.
Nat Immunol ; 13(12): 1162-70, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23086447

RESUMO

The NF-κB protein RelB controls dendritic cell (DC) maturation and may be targeted therapeutically to manipulate T cell responses in disease. Here we report that RelB promoted DC activation not as the expected RelB-p52 effector of the noncanonical NF-κB pathway, but as a RelB-p50 dimer regulated by canonical IκBs, IκBα and IκBɛ. IκB control of RelB minimized spontaneous maturation but enabled rapid pathogen-responsive maturation. Computational modeling of the NF-κB signaling module identified control points of this unexpected cell type-specific regulation. Fibroblasts that we engineered accordingly showed DC-like RelB control. Canonical pathway control of RelB regulated pathogen-responsive gene expression programs. This work illustrates the potential utility of systems analyses in guiding the development of combination therapeutics for modulating DC-dependent T cell responses.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Ativação Linfocitária , NF-kappa B/metabolismo , Fator de Transcrição RelB/metabolismo , Animais , Diferenciação Celular/genética , Linhagem Celular , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Quinase I-kappa B/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/genética , Multimerização Proteica , Transdução de Sinais , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Receptor Toll-Like 9/metabolismo , Fator de Transcrição RelB/genética
3.
Pediatr Res ; 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443525

RESUMO

BACKGROUND: T-Cell Receptor Excision Circles based newborn screening (TREC-NBS) allows for early detection of T-cell lymphopenia in infants with primary immunodeficiency disorders (PIDD). The utility of abnormal TREC-NBS in infants without PIDD is not well studied. We sought to evaluate the association of abnormal TREC-NBS with mortality. METHODS: 365,207 TREC-NBS from October 2011 to December 2014 were reviewed. 467 newborns had abnormal screens and did not meet the criteria for a PIDD diagnosis. Cases were matched to controls (1:3) based on gestational age, birth weight, neonatal intensive care unit status (NICU), and race. Data were obtained through NBS, birth and death certificates records from the Michigan Department of Health and Human Services (MDHHS) databases. RESULTS: Infants with abnormal TREC-NBS had higher mortality even when PIDD was ruled-out. Transient abnormal TREC-NBS was not associated with higher mortality, but unresolved or late abnormal TREC-NBS was associated with higher mortality. Infants with late abnormal TREC-NBS had severe prematurity, lower birth weight, lower Apgar scores, and higher percentage of congenital anomalies. CONCLUSION: Infants with abnormal TREC-NBS may be at a higher risk of morbidity and mortality and should be carefully followed, especially if discharged home before a repeat screen can be completed. IMPACT: This study explores the risk factors and mortality for newborns with secondary T-cell lymphopenia captured on T-Cell Receptor Excision Circles based newborn screening (TREC-NBS). Abnormal TREC-NBS allows for prompt life-saving interventions for primary immunological conditions such as Severe Combined Immunodeficiency (SCID), but can also be associated with non-immunologic conditions. Unresolved and late abnormal TREC-NBS is associated with higher mortality even without primary immunodeficiency, likely detected in infants with more severe prematurity, lower birth weight, and congenital anomalies. TREC-NBS positive infants with secondary T-cell lymphopenia require special attention and close monitoring.

4.
Stat Med ; 43(10): 1867-1882, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38409877

RESUMO

Throughout the course of an epidemic, the rate at which disease spreads varies with behavioral changes, the emergence of new disease variants, and the introduction of mitigation policies. Estimating such changes in transmission rates can help us better model and predict the dynamics of an epidemic, and provide insight into the efficacy of control and intervention strategies. We present a method for likelihood-based estimation of parameters in the stochastic susceptible-infected-removed model under a time-inhomogeneous transmission rate comprised of piecewise constant components. In doing so, our method simultaneously learns change points in the transmission rate via a Markov chain Monte Carlo algorithm. The method targets the exact model posterior in a difficult missing data setting given only partially observed case counts over time. We validate performance on simulated data before applying our approach to data from an Ebola outbreak in Western Africa and COVID-19 outbreak on a university campus.


Assuntos
Epidemias , Doença pelo Vírus Ebola , Humanos , Funções Verossimilhança , Cadeias de Markov , Surtos de Doenças , Método de Monte Carlo , Teorema de Bayes , Processos Estocásticos
5.
Allergy Asthma Proc ; 45(2): 100-107, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38449014

RESUMO

Background: Inner-city asthma is associated with high morbidity and systemic steroid use. Chronic steroid use impacts immune function; however, there is a lack of data with regard to the extent of immunosuppression in patients with asthma and who are receiving frequent systemic steroids. Objective: To identify the impact of frequent systemic steroid bursts on the immune function of children with asthma who live in the inner city. Methods: Children ages 3-18 years with asthma were divided into study (≥2 systemic steroid bursts/year) and control groups (0-1 systemic steroid bursts/year). Lymphocyte subsets; mitogen proliferation assay; total immunoglobulin G (IgG) value, and pneumococcal and diphtheria/tetanus IgG values were evaluated. Results: Ninety-one participants were enrolled (study group [n = 42] and control group [n = 49]). There was no difference in adequate pneumococcal IgG value, diphtheria/tetanus IgG value, mitogen proliferation assays, lymphocyte subsets, and IgG values between the two groups. Children who received ≥2 steroid bursts/year had a significantly lower median pneumococcal IgG serotype 7F value. Most of the immune laboratory results were normal except for the pneumococcal IgG value. Most of the participants (n/N = 72/91 [79%]) had an inadequate pneumococcal IgG level (<7/14 serotypes ≥1.3 µg/mL). The participants with inadequate pneumococcal IgG level and who received a pneumococcal polysaccharide vaccine 23 (PPSV23) boost had a robust response. There was no significant difference in infection, steroid exposure, asthma severity, or morbidities between those with adequate versus inadequate pneumococcal IgG values. Conclusion: Children with asthma who live in the inner city and receive ≥2 steroid bursts/year do not have a significantly different immune profile from those who receive ≤1 steroid bursts/year do not have a significantly different immune profile from those who do not. Although appropriately vaccinated, most participants had an inadequate pneumococcal IgG level, regardless of steroid exposure and asthma severity. These children may benefit from PPSV23.


Assuntos
Asma , Difteria , Tétano , Criança , Humanos , Mitógenos , Imunoglobulina G , Anticorpos Antibacterianos , Asma/tratamento farmacológico , Vacinas Pneumocócicas , Esteroides
6.
Am J Transplant ; 23(11): 1757-1770, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37321454

RESUMO

This study aimed to synthesize the available evidence on the immunogenicity, safety, and effectiveness of live-attenuated varicella vaccine in solid organ transplant recipients. Medline and EMBASE were searched using predefined search terms to identify relevant studies. The included articles reported varicella vaccine administration in the posttransplant period in children and adults. A pooled proportion of transplant recipients who seroconverted and who developed vaccine-strain varicella and varicella disease was generated. Eighteen articles (14 observational studies and 4 case reports) were included, reporting on 711 transplant recipients who received the varicella vaccine. The pooled proportion was 88.2% (95% confidence interval 78.0%-96.0%, 13 studies) for vaccinees who seroconverted, 0% (0%-1.2%, 13 studies) for vaccine-strain varicella, and 0.8% (0%-4.9%, 9 studies) for varicella disease. Most studies followed clinical guidelines for administering live-attenuated vaccines, with criteria that could include being at least 1 year posttransplant, 2 months postrejection episode, and on low-dose immunosuppressive medications. Varicella vaccination in transplant recipients was overall safe in the included studies, with few cases of vaccine-strain-induced varicella or vaccine failure, and although it was immunogenic, the proportion of recipients who seroconverted was lower than that seen in the general population. Our data support varicella vaccination in select pediatric solid organ transplant recipients.


Assuntos
Varicela , Transplante de Órgãos , Vacinas Virais , Adulto , Criança , Humanos , Varicela/prevenção & controle , Transplantados , Vacina contra Varicela/efeitos adversos , Vacinas Atenuadas
7.
N Engl J Med ; 382(12): 1112-1123, 2020 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-32130809

RESUMO

BACKGROUND: Simplified regimens for the treatment of human immunodeficiency virus type 1 (HIV-1) infection may increase patient satisfaction and facilitate adherence. METHODS: In this phase 3, open-label, multicenter, noninferiority trial involving patients who had had plasma HIV-1 RNA levels of less than 50 copies per milliliter for at least 6 months while taking standard oral antiretroviral therapy, we randomly assigned participants (1:1) to either continue their oral therapy or switch to monthly intramuscular injections of long-acting cabotegravir, an HIV-1 integrase strand-transfer inhibitor, and long-acting rilpivirine, a nonnucleoside reverse-transcriptase inhibitor. The primary end point was the percentage of participants with an HIV-1 RNA level of 50 copies per milliliter or higher at week 48, determined with the use of the Food and Drug Administration snapshot algorithm. RESULTS: Treatment was initiated in 308 participants per group. At week 48, HIV-1 RNA levels of 50 copies per milliliter or higher were found in 5 participants (1.6%) receiving long-acting therapy and in 3 (1.0%) receiving oral therapy (adjusted difference, 0.6 percentage points; 95% confidence interval [CI], -1.2 to 2.5), a result that met the criterion for noninferiority for the primary end point (noninferiority margin, 6 percentage points). An HIV-1 RNA level of less than 50 copies per milliliter at week 48 was found in 92.5% of participants receiving long-acting therapy and in 95.5% of those receiving oral therapy (adjusted difference, -3.0 percentage points; 95% CI, -6.7 to 0.7), a result that met the criterion for noninferiority for this end point (noninferiority margin, -10 percentage points). Virologic failure was confirmed in 3 participants who received long-acting therapy and 4 participants who received oral therapy. Adverse events were more common in the long-acting-therapy group and included injection-site pain, which occurred in 231 recipients (75%) of long-acting therapy and was mild or moderate in most cases; 1% withdrew because of this event. Serious adverse events were reported in no more than 5% of participants in each group. CONCLUSIONS: Monthly injections of long-acting cabotegravir and rilpivirine were noninferior to standard oral therapy for maintaining HIV-1 suppression. Injection-related adverse events were common but only infrequently led to medication withdrawal. (Funded by ViiV Healthcare and Janssen; ATLAS ClinicalTrials.gov number, NCT02951052.).


Assuntos
Fármacos Anti-HIV/administração & dosagem , Infecções por HIV/tratamento farmacológico , HIV-1/isolamento & purificação , Piridonas/administração & dosagem , Rilpivirina/administração & dosagem , Administração Oral , Adulto , Fármacos Anti-HIV/efeitos adversos , Fármacos Anti-HIV/sangue , Antirretrovirais/uso terapêutico , Contagem de Linfócito CD4 , Farmacorresistência Viral/genética , Quimioterapia Combinada , Feminino , HIV-1/genética , Humanos , Injeções Intramusculares/efeitos adversos , Quimioterapia de Manutenção , Masculino , Pessoa de Meia-Idade , Mutação , Medidas de Resultados Relatados pelo Paciente , Piridonas/efeitos adversos , Piridonas/sangue , RNA Viral/sangue , Rilpivirina/efeitos adversos , Rilpivirina/sangue , Carga Viral
8.
Clin Exp Immunol ; 213(2): 252-264, 2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37191586

RESUMO

Transplant-associated thrombotic microangiopathy (TA-TMA) is an endotheliopathy complicating up to 30% of allogeneic hematopoietic stem cell transplants (alloHSCT). Positive feedback loops among complement, pro-inflammatory, pro-apoptotic, and coagulation cascade likely assume dominant roles at different disease stages. We hypothesized that mannose-binding lectin-associated serine protease 2 (MASP2), principal activator of the lectin complement system, is involved in the microvascular endothelial cell (MVEC) injury characteristic of TA-TMA through pathways that are susceptible to suppression by anti-MASP2 monoclonal antibody narsoplimab. Pre-treatment plasmas from 8 of 9 TA-TMA patients achieving a complete TMA response in a narsoplimab clinical trial activated caspase 8, the initial step in apoptotic injury, in human MVEC. This was reduced to control levels following narsoplimab treatment in 7 of the 8 subjects. Plasmas from 8 individuals in an observational TA-TMA study, but not 8 alloHSCT subjects without TMA, similarly activated caspase 8, which was blocked in vitro by narsoplimab. mRNA sequencing of MVEC exposed to TA-TMA or control plasmas with and without narsoplimab suggested potential mechanisms of action. The top 40 narsoplimab-affected transcripts included upregulation of SerpinB2, which blocks apoptosis by inactivating procaspase 3; CHAC1, which inhibits apoptosis in association with mitigation of oxidative stress responses; and pro-angiogenesis proteins TM4SF18, ASPM, and ESM1. Narsoplimab also suppressed transcripts encoding pro-apoptotic and pro-inflammatory proteins ZNF521, IL1R1, Fibulin-5, aggrecan, SLC14A1, and LOX1, and TMEM204, which disrupts vascular integrity. Our data suggest benefits to narsoplimab use in high-risk TA-TMA and provide a potential mechanistic basis for the clinical efficacy of narsoplimab in this disorder.


Assuntos
Anticorpos Monoclonais Humanizados , Transplante de Células-Tronco Hematopoéticas , Serina Proteases Associadas a Proteína de Ligação a Manose , Microangiopatias Trombóticas , Humanos , Anticorpos Monoclonais Humanizados/uso terapêutico , Caspase 8/genética , Caspase 8/uso terapêutico , Proteínas do Sistema Complemento , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Serina Proteases Associadas a Proteína de Ligação a Manose/antagonistas & inibidores , Serina Proteases Associadas a Proteína de Ligação a Manose/genética , Microangiopatias Trombóticas/tratamento farmacológico , Microangiopatias Trombóticas/etiologia , Microangiopatias Trombóticas/genética , Resultado do Tratamento
9.
Stat Med ; 42(28): 5189-5206, 2023 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-37705508

RESUMO

Intensive care occupancy is an important indicator of health care stress that has been used to guide policy decisions during the COVID-19 pandemic. Toward reliable decision-making as a pandemic progresses, estimating the rates at which patients are admitted to and discharged from hospitals and intensive care units (ICUs) is crucial. Since individual-level hospital data are rarely available to modelers in each geographic locality of interest, it is important to develop tools for inferring these rates from publicly available daily numbers of hospital and ICU beds occupied. We develop such an estimation approach based on an immigration-death process that models fluctuations of ICU occupancy. Our flexible framework allows for immigration and death rates to depend on covariates, such as hospital bed occupancy and daily SARS-CoV-2 test positivity rate, which may drive changes in hospital ICU operations. We demonstrate via simulation studies that the proposed method performs well on noisy time series data and apply our statistical framework to hospitalization data from the University of California, Irvine (UCI) Health and Orange County, California. By introducing a likelihood-based framework where immigration and death rates can vary with covariates, we find, through rigorous model selection, that hospitalization and positivity rates are crucial covariates for modeling ICU stay dynamics and validate our per-patient ICU stay estimates using anonymized patient-level UCI hospital data.


Assuntos
Ocupação de Leitos , Cuidados Críticos , Unidades de Terapia Intensiva , Humanos , COVID-19/epidemiologia , Hospitalização , Funções Verossimilhança , Pandemias , SARS-CoV-2 , Fatores de Tempo , Processos Estocásticos
10.
Clin Oral Investig ; 27(9): 5595-5604, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37493728

RESUMO

OBJECTIVES: External cervical root resorption (ECR) is a poorly understood and aggressive form of resorption. The purpose of this study was to examine the prevalence, characteristics, and risk factors associated with the occurrence of ECR in patients seeking endodontic care from private practice settings. MATERIALS AND METHODS: Records of 343 patients with 390 teeth diagnosed with ECR were identified from 3 private endodontic practices from 2008 to 2022. The patients' demographic information, systemic conditions, and dental history were recorded. The characteristics of the cases including Heithersay classification, pulpal and periapical status, and their management were documented. The association between case severity and potential predisposing factors was examined using chi-square analysis. RESULTS: The overall prevalence of ECR among patients seeking endodontic care was low (< 1%). However, there was a greater than twofold increase in the pooled prevalence from 2016 to 2021 (0.99%) compared to the data from 2010 to 2015 (0.46%). The most commonly affected teeth were anterior teeth (48.7%). Class II (30.0%) and class III (45.4%) defects were the most often identified. Patients with a history of trauma or orthodontic treatment were significantly more likely to be diagnosed with severe cervical resorption (class III or IV) (p < 0.05). CONCLUSIONS: There has been an increase in the prevalence of ECR in patients seeking endodontic care. A history of orthodontic treatment and traumatic dental mechanical injuries may predict the severity of resorption. CLINICAL RELEVANCE: The upward trend in the occurrence of ECR warrants close monitoring of the patients at high risk of developing the condition to facilitate early detection and management.


Assuntos
Reabsorção da Raiz , Reabsorção de Dente , Humanos , Estudos Retrospectivos , Reabsorção da Raiz/epidemiologia , Reabsorção da Raiz/terapia , Colo do Dente , Prevalência , Fatores de Risco
11.
Radiology ; 305(2): 454-465, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35852426

RESUMO

Background Developing deep learning models for radiology requires large data sets and substantial computational resources. Data set size limitations can be further exacerbated by distribution shifts, such as rapid changes in patient populations and standard of care during the COVID-19 pandemic. A common partial mitigation is transfer learning by pretraining a "generic network" on a large nonmedical data set and then fine-tuning on a task-specific radiology data set. Purpose To reduce data set size requirements for chest radiography deep learning models by using an advanced machine learning approach (supervised contrastive [SupCon] learning) to generate chest radiography networks. Materials and Methods SupCon helped generate chest radiography networks from 821 544 chest radiographs from India and the United States. The chest radiography networks were used as a starting point for further machine learning model development for 10 prediction tasks (eg, airspace opacity, fracture, tuberculosis, and COVID-19 outcomes) by using five data sets comprising 684 955 chest radiographs from India, the United States, and China. Three model development setups were tested (linear classifier, nonlinear classifier, and fine-tuning the full network) with different data set sizes from eight to 85. Results Across a majority of tasks, compared with transfer learning from a nonmedical data set, SupCon reduced label requirements up to 688-fold and improved the area under the receiver operating characteristic curve (AUC) at matching data set sizes. At the extreme low-data regimen, training small nonlinear models by using only 45 chest radiographs yielded an AUC of 0.95 (noninferior to radiologist performance) in classifying microbiology-confirmed tuberculosis in external validation. At a more moderate data regimen, training small nonlinear models by using only 528 chest radiographs yielded an AUC of 0.75 in predicting severe COVID-19 outcomes. Conclusion Supervised contrastive learning enabled performance comparable to state-of-the-art deep learning models in multiple clinical tasks by using as few as 45 images and is a promising method for predictive modeling with use of small data sets and for predicting outcomes in shifting patient populations. © RSNA, 2022 Online supplemental material is available for this article.


Assuntos
COVID-19 , Aprendizado Profundo , Humanos , Radiografia Torácica/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Pandemias , COVID-19/diagnóstico por imagem , Estudos Retrospectivos , Radiografia , Aprendizado de Máquina
12.
Proc Natl Acad Sci U S A ; 115(18): 4607-4612, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29666239

RESUMO

The French Revolution brought principles of "liberty, equality, fraternity" to bear on the day-to-day challenges of governing what was then the largest country in Europe. Its experiments provided a model for future revolutions and democracies across the globe, but this first modern revolution had no model to follow. Using reconstructed transcripts of debates held in the Revolution's first parliament, we present a quantitative analysis of how this body managed innovation. We use information theory to track the creation, transmission, and destruction of word-use patterns across over 40,000 speeches and a thousand speakers. The parliament as a whole was biased toward the adoption of new patterns, but speakers' individual qualities could break these overall trends. Speakers on the left innovated at higher rates, while speakers on the right acted to preserve prior patterns. Key players such as Robespierre (on the left) and Abbé Maury (on the right) played information-processing roles emblematic of their politics. Newly created organizational functions-such as the Assembly president and committee chairs-had significant effects on debate outcomes, and a distinct transition appears midway through the parliament when committees, external to the debate process, gained new powers to "propose and dispose." Taken together, these quantitative results align with existing qualitative interpretations, but also reveal crucial information-processing dynamics that have hitherto been overlooked. Great orators had the public's attention, but deputies (mostly on the political left) who mastered the committee system gained new powers to shape revolutionary legislation.

13.
AIDS Behav ; 24(12): 3533-3544, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32447500

RESUMO

The phase 3 ATLAS and FLAIR studies demonstrated that maintenance with Long-Acting (LA) intramuscular cabotegravir and rilpivirine is non-inferior in efficacy to current antiretroviral (CAR) oral therapy. Both studies utilized Patient-Reported Outcome instruments to measure treatment satisfaction (HIVTSQ) and acceptance (ACCEPT general domain), health status (SF-12), injection tolerability/acceptance (PIN), and treatment preference. In pooled analyses, LA-treated patients (n = 591) demonstrated greater mean improvements from baseline than the CAR group (n = 591) in treatment satisfaction (Week 44, + 3.9 vs. +0.5 HIVTSQs-points; p < 0.001) and acceptance (Week 48, +8.8 vs. +2.0 ACCEPT-points; p < 0.001). The acceptability of injection site reactions (PIN) significantly improved from week 5 (2.10 points) to week 48 (1.62 points; p < 0.001). In both studies, ≥ 97% of LA group participants with recorded data preferred LA treatment compared with prior oral therapy. These results further support the potential of a monthly injectable option for people living with HIV seeking an alternative to daily oral treatment.


Assuntos
Fármacos Anti-HIV/uso terapêutico , Infecções por HIV , HIV-1 , Piridonas/uso terapêutico , Rilpivirina/uso terapêutico , Infecções por HIV/tratamento farmacológico , Humanos , Injeções Intramusculares , Medidas de Resultados Relatados pelo Paciente
14.
Gastroenterology ; 165(2): 307-308, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37031911
15.
JAMA ; 329(22): 1981-1982, 2023 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-37234011

RESUMO

This JAMA Insights in the Women's Health series examines the management of asthma during pregnancy, including diagnosis, treatment, and the handling of exacerbations.


Assuntos
Asma , Complicações na Gravidez , Feminino , Humanos , Gravidez , Asma/tratamento farmacológico , Complicações na Gravidez/terapia , Saúde da Mulher
17.
J Virol ; 90(17): 7789-97, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27334590

RESUMO

UNLABELLED: Several innate sensing pathways contribute to the control of early cytomegalovirus (CMV) infection, leading to a multiphasic type I interferon (IFN-I) response that limits viral replication and promotes host defenses. Toll-like receptor (TLR)-dependent pathways induce IFN-I production in CMV-infected plasmacytoid dendritic cells; however, the initial burst of IFN-I that occurs within the first few hours in vivo is TLR independent and emanates from stromal cells. Here we show that primary human endothelial cells mount robust IFN-I responses to human CMV that are dependent upon cyclic GMP-AMP synthase (cGAS), STING, and interferon regulatory factor 3 (IRF3) signaling. Disruption of STING expression in endothelial cells by clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 revealed that it is essential for the induction of IFN-I and restriction of CMV replication. Consistently, STING was necessary to mount the first phase of IFN-I production and curb CMV replication in infected mice. Thus, DNA sensing through STING is critical for primary detection of both human and mouse CMV in nonhematopoietic cells and drives the initial wave of IFN-I that is key for controlling early viral replication in vivo. IMPORTANCE: Cytomegalovirus (CMV) is one of the most common viral pathogens, with the majority of people contracting the virus in their lifetime. Although acute infection is mostly asymptomatic in healthy persons, significant pathology is observed in immunocompromised individuals, and chronic CMV infection may exacerbate a myriad of inflammatory conditions. Here we show that primary human endothelial cells mount robust IFN-I responses against CMV via a cGAS/STING/IRF3 pathway. Disruption of STING expression by CRISPRs revealed an essential role in eliciting IFN-I responses and restricting CMV replication. Consistently, in mice, STING is necessary for the first phase of IFN-I production that limits early CMV replication. Our results demonstrate a pivotal role for the cGAS-STING pathway in the initial detection of CMV infection.


Assuntos
Infecções por Citomegalovirus/imunologia , Células Endoteliais/imunologia , Células Endoteliais/virologia , Imunidade Inata , Proteínas de Membrana/metabolismo , Nucleotidiltransferases/metabolismo , Transdução de Sinais , Animais , Modelos Animais de Doenças , Células Endoteliais da Veia Umbilical Humana , Humanos , Fator Regulador 3 de Interferon/metabolismo , Interferon Tipo I/metabolismo , Camundongos Endogâmicos C57BL
18.
Mol Pharmacol ; 89(4): 425-34, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26837243

RESUMO

Pemetrexed (PMX) is a 5-substituted pyrrolo[2,3-d]pyrimidine antifolate used for therapy of nonsquamous nonsmall cell lung cancer (NS-NSCLC). PMX is transported by the reduced folate carrier (RFC) and proton-coupled folate transporter (PCFT). Unlike RFC, PCFT is active at acidic pH levels characterizing the tumor microenvironment. By real-time reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, PCFT transcripts and proteins were detected in primary NS-NSCLC specimens. In six NS-NSCLC cell lines (A549, H1437, H460, H1299, H1650, and H2030), PCFT transcripts and proteins were detected by real-time RT-PCR and western blots, respectively. 6-Substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolates related to PMX [compound 1 (C1) and compound 2 (C2), respectively] are selective substrates for PCFT over RFC. In the NS-NSCLC cell lines, both [(3)H]PMX and [(3)H]C2 were transported by PCFT. C1 and C2 inhibited proliferation of the NS-NSCLC cell lines; A549, H460, and H2030 cells were more sensitive to C1 than to PMX. C1 and C2 inhibited glycinamide ribonucleotide formyltransferase in de novo purine nucleotide biosynthesis. When treated at pH 6.8, which favors PCFT uptake, C1 and C2 inhibited clonogenicity of H460 cells greater than PMX; PMX inhibited clonogenicity more than C1 or C2 at pH 7.2, which favors RFC transport over PCFT. Knockdown of PCFT in H460 cells resulted in decreased [(3)H]PMX and [(3)H]C2 transport and decreased growth inhibition by C1 and C2, and to a lesser extent by PMX. In vivo efficacy of C1 was seen toward H460 tumor xenografts in severe-combined immunodeficient mice. Our results suggest that 6-substituted pyrrolo[2,3-d]pyrimidine thienoyl antifolates offer significant promise for treating NS-NSCLC by selective uptake by PCFT.


Assuntos
Antineoplásicos/metabolismo , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Antagonistas do Ácido Fólico/metabolismo , Neoplasias Pulmonares/metabolismo , Transportador de Folato Acoplado a Próton/metabolismo , Animais , Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Feminino , Antagonistas do Ácido Fólico/administração & dosagem , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Camundongos , Camundongos Endogâmicos ICR , Camundongos SCID , Pirimidinas/administração & dosagem , Pirimidinas/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
19.
Biochem J ; 469(1): 33-44, 2015 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-25877470

RESUMO

The human proton-coupled folate transporter (hPCFT) is expressed in solid tumours and is active at pHs characterizing the tumour microenvironment. Recent attention focused on exploiting hPCFT for targeting solid tumours with novel cytotoxic anti-folates. hPCFT has 12 transmembrane domains (TMDs) and forms homo-oligomers with functional significance. The hPCFT primary sequence includes GXXXG motifs in TMD2 (G(93)XXXG(97)) and TMD4 (G(155)XXXG(159)). To investigate roles of these motifs in hPCFT function, stability and surface expression, we mutated glycine to leucine to generate single or multiple substitution mutants. Only the G93L and G159L mutants preserved substantial [(3)H]methotrexate (Mtx) transport when expressed in hPCFT-null (R1-11) HeLa cells. Transport activity of the glycine-to-leucine mutants correlated with surface hPCFT by surface biotinylation and confocal microscopy with ECFP*-tagged hPCFTs, suggesting a role for GXXXG in hPCFT stability and intracellular trafficking. When co-expressed in R1-11 cells, haemagglutinin-tagged glycine-to-leucine mutants and His10-tagged wild-type (WT) hPCFT co-associated on nickel affinity columns, suggesting that the GXXXG motifs are not directly involved in hPCFT oligomerization. This was substantiated by in situ FRET experiments with co-expressed ECFP*- and YFP-tagged hPCFT. Molecular modelling of dimeric hPCFT structures showed juxtaposed TMDs 2, 3, 4 and 6 as potential structural interfaces between monomers. hPCFT cysteine insertion mutants in TMD3 (Q136C and L137C) and TMD6 (W213C, L214C, L224C, A227C, F228C, F230C and G231C) were expressed in R1-11 cells and cross-linked with 1,6-hexanediyl bismethanethiosulfonate, confirming TMD juxtapositions. Altogether, our results imply that TMDs 3 and 6 provide critical interfaces for formation of hPCFT oligomers, which might be facilitated by the GXXXG motifs in TMD2 and TMD4.


Assuntos
Complexos Multiproteicos/química , Complexos Multiproteicos/metabolismo , Multimerização Proteica/fisiologia , Transportador de Folato Acoplado a Próton/química , Transportador de Folato Acoplado a Próton/metabolismo , Motivos de Aminoácidos , Substituição de Aminoácidos , Células HeLa , Humanos , Complexos Multiproteicos/genética , Mutação de Sentido Incorreto , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Transportador de Folato Acoplado a Próton/genética
20.
Neuroimage ; 106: 428-40, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25463462

RESUMO

Resting state functional connectivity (rFC) is used to identify functionally related brain areas without requiring subjects to perform specific tasks. Previous work suggests that prior brain state, as determined by the activity engaged in immediately prior to collection of resting state data, can influence the networks recovered by rFC analyses. We determined the prevalence and network specificity of rFC changes induced by manipulations of prior state (including an unstructured (unconstrained) state, and language and motor tasks). Three blocks of rest data (one after each of the specified prior states) were acquired on each of 25 subjects. We hypothesised that prior state induced changes in rFC would be greatest within the networks most actively recruited by that prior state. Changes in rFC were greatest following the motor task and, contrary to our hypothesis, were not network specific. This was demonstrated by comparing (1) the timecourses within a set of ROIs selected on the basis of task-related de/activation, and (2) seed-based whole brain voxel-wise connectivity maps, seeded from local maxima in the task-related de/activation maps. Changes in connectivity strength tended to manifest as increases in rFC relative to that in the unstructured rest state, with change maps resembling partially complete maps of the primary sensory cortices and the cognitive control network. The majority of rFC changes occurred in areas moderately (but not weakly) connected to the seeds. Constrained prior states were associated with lower across-participant variance in rFC. This systematic investigation of the effect of prior brain state on rFC indicates that the rFC changes induced by prior brain state occur both in brain networks related to that brain activity and in networks nominally unrelated to that brain activity.


Assuntos
Encéfalo/fisiologia , Cognição/fisiologia , Rede Nervosa/fisiologia , Adolescente , Adulto , Mapeamento Encefálico , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Atividade Motora , Descanso/fisiologia , Adulto Jovem
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