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1.
J Am Coll Surg ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651746

RESUMO

BACKGROUND: Colorectal cancer (CRC) is the third most common cause of cancer mortality worldwide. Of these, approximately 25% will have liver metastasis. We performed 394 microwave ablations (MWA) and analyzed outcomes for survival and ablation failure. STUDY DESIGN: Retrospective review of patients who underwent a surgical microwave ablation at a single center high-volume institution from October 2006 through September 2022 using a prospectively maintained database. Primary outcome was overall survival. RESULTS: A total of 394 operations were performed on 328 patients with 842 tumors undergoing MWA. Median tumor size was 1.5 cm (range 0.4-7.0 cm), with the median number of tumors ablated per operation being 1 (range 1-11). A laparoscopic approach was used 77.9% of the time. Concomitant procedures were performed 63% of the time, most commonly hepatectomy (22.3%), cholecystectomy (17.5%), and colectomy (6.6%). Clavien-Dindo Grade III or IV complications occurred in 12 patients (3.6%), and all of these patients had undergone concomitant procedures. Mortality within 30 days occurred in 4 patients (1.2%). The rate of incomplete ablation (IA) was 1.5% per tumor. Local recurrence (LR) occurred at a rate of 6.3% per tumor. African Americans were found to have a higher incidence of IA and LR. One year survival probability was 91% [95% CI: 87.9 -94.3], with a mean overall survival of 57.6 months [95% CI: 49.9-65.4 months]. CONCLUSION: Surgical MWA offers a low-morbidity approach to treatment of colorectal liver metastasis (CRLM), with low rates of failure. This large series reviews the outcomes of MWA as definitive treatment for CRLM.

2.
J Surg Case Rep ; 2024(3): rjae174, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38524682

RESUMO

Renal angiomyolipoma (AML) is a benign tumor with rare venous extension. We present a case of a patient with renal AML with inferior vena cava (IVC) tumor thrombus and acute pulmonary embolism (PE). A 34-year-old female presented with chest pain. Imaging revealed a 5 cm right renal AML, with tumor thrombus into the renal vein and IVC, and acute left lower lobe PE. Right radical nephrectomy and caval thrombectomy were performed using intraoperative ultrasound. Rarely, these benign tumors generate thrombus with caval extension. The location of IVC thrombus guides surgical planning, which may involve suprahepatic IVC control or cardiopulmonary bypass. Early involvement of a multidisciplinary team with extensive preoperative planning can help achieve successful outcomes.

3.
HPB (Oxford) ; 26(3): 379-388, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38102029

RESUMO

INTRODUCTION: Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality and often arises in the setting of cirrhosis. The present series reviews outcomes following 791 operations. METHODS: Retrospective review surgical MWA for HCC from March 2007 through December 2022 at a high-volume institution was performed using a prospective database. Primary outcome was overall survival. RESULTS: A total of 791 operations in 623 patients and 1156 HCC tumors were treated with surgical MWA. Median tumor size was 2 cm (range 0.25-10 cm) with an average of 1 tumor ablated per operation (range 1-7 tumors). Nearly 90 % of patients had cirrhosis with a median MELD score of 8 (IQR = 6-11). Mortality within 30 days occurred in 13 patients (1.6 %). Per tumor, the rate of incomplete ablation was 2.25 % and local recurrence was 2.95 %. Previous ablation and tumor size were risk factors for recurrence. One-year overall survival was 82.0 % with a median overall survival of 36.5 months (95 % CI 15.7-93.7) and median disease-free survival of 15.9 months (range 5.7-37.3 months). CONCLUSION: Surgical MWA offers a low-morbidity approach for treatment of HCC, affording low rates of incomplete ablation and local recurrence.


Assuntos
Carcinoma Hepatocelular , Ablação por Cateter , Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/patologia , Micro-Ondas/efeitos adversos , Resultado do Tratamento , Cirrose Hepática/cirurgia , Estudos Retrospectivos
4.
Nat Microbiol ; 8(8): 1587-1599, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37443277

RESUMO

LY6E is an antiviral restriction factor that inhibits coronavirus spike-mediated fusion, but the cell types in vivo that require LY6E for protection from respiratory coronavirus infection are unknown. Here we used a panel of seven conditional Ly6e knockout mice to define which Ly6e-expressing cells confer control of airway infection by murine coronavirus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Loss of Ly6e in Lyz2-expressing cells, radioresistant Vav1-expressing cells and non-haematopoietic cells increased susceptibility to murine coronavirus. Global conditional loss of Ly6e expression resulted in clinical disease and higher viral burden after SARS-CoV-2 infection, but little evidence of immunopathology. We show that Ly6e expression protected secretory club and ciliated cells from SARS-CoV-2 infection and prevented virus-induced loss of an epithelial cell transcriptomic signature in the lung. Our study demonstrates that lineage confined rather than broad expression of Ly6e sufficiently confers resistance to disease caused by murine and human coronaviruses.


Assuntos
COVID-19 , Humanos , Camundongos , Animais , SARS-CoV-2/metabolismo , Pulmão , Antivirais/farmacologia , Células Epiteliais/metabolismo , Camundongos Knockout , Antígenos de Superfície/metabolismo , Proteínas Ligadas por GPI
5.
mBio ; 14(2): e0012723, 2023 04 25.
Artigo em Inglês | MEDLINE | ID: mdl-36809113

RESUMO

Viruses are known to co-opt host machinery for translation initiation, but less is known about which host factors are required for the formation of ribosomes used to synthesize viral proteins. Using a loss-of-function CRISPR screen, we show that synthesis of a flavivirus-encoded fluorescent reporter depends on multiple host factors, including several 60S ribosome biogenesis proteins. Viral phenotyping revealed that two of these factors, SBDS, a known ribosome biogenesis factor, and the relatively uncharacterized protein SPATA5, were broadly required for replication of flaviviruses, coronaviruses, alphaviruses, paramyxoviruses, an enterovirus, and a poxvirus. Mechanistic studies revealed that loss of SPATA5 caused defects in rRNA processing and ribosome assembly, suggesting that this human protein may be a functional ortholog of yeast Drg1. These studies implicate specific ribosome biogenesis proteins as viral host dependency factors that are required for synthesis of virally encoded protein and accordingly, optimal viral replication. IMPORTANCE Viruses are well known for their ability to co-opt host ribosomes to synthesize viral proteins. The specific factors involved in translation of viral RNAs are not fully described. In this study, we implemented a unique genome-scale CRISPR screen to identify previously uncharacterized host factors that are important for the synthesis of virally encoded protein. We found that multiple genes involved in 60S ribosome biogenesis were required for viral RNA translation. Loss of these factors severely impaired viral replication. Mechanistic studies on the AAA ATPase SPATA5 indicate that this host factor is required for a late step in ribosome formation. These findings reveal insight into the identity and function of specific ribosome biogenesis proteins that are critical for viral infections.


Assuntos
Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Flavivirus , Humanos , Ribossomos/metabolismo , Proteínas Virais/genética , Proteínas Virais/metabolismo , Replicação Viral , RNA Viral/genética , RNA Viral/metabolismo , ATPases Associadas a Diversas Atividades Celulares/metabolismo
6.
Nat Commun ; 13(1): 6456, 2022 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-36309510

RESUMO

Communicable respiratory viral infections pose both epidemic and pandemic threats and broad-spectrum antiviral strategies could improve preparedness for these events. To discover host antiviral restriction factors that may act as suitable targets for the development of host-directed antiviral therapies, we here conduct a whole-genome CRISPR activation screen with influenza B virus (IBV). A top hit from our screen, beta-1,3-glucuronyltransferase 1 (B3GAT1), effectively blocks IBV infection. Subsequent studies reveal that B3GAT1 activity prevents cell surface sialic acid expression. Due to this mechanism of action, B3GAT1 expression broadly restricts infection with viruses that require sialic acid for entry, including Victoria and Yamagata lineage IBVs, H1N1/H3N2 influenza A viruses (IAVs), and the unrelated enterovirus D68. To understand the potential utility of B3GAT1 induction as an antiviral strategy in vivo, we specifically express B3GAT1 in the murine respiratory epithelium and find that overexpression is not only well-tolerated, but also protects female mice from a lethal viral challenge with multiple influenza viruses, including a pandemic-like H1N1 IAV. Thus, B3GAT1 may represent a host-directed broad-spectrum antiviral target with utility against clinically relevant respiratory viruses.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Influenza Humana , Infecções por Orthomyxoviridae , Feminino , Camundongos , Animais , Humanos , Vírus da Influenza A Subtipo H3N2 , Ácido N-Acetilneuramínico , Vírus da Influenza B , Antivirais/farmacologia , Polissacarídeos , Glucuronosiltransferase
7.
J Virol ; 96(13): e0033022, 2022 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-35699446

RESUMO

Echoviruses are among the most common worldwide causes of aseptic meningitis, which can cause long-term sequelae and death, particularly in neonates. However, the mechanisms by which these viruses induce meningeal inflammation are poorly understood, owing at least in part to the lack of in vivo models that recapitulate this aspect of echovirus pathogenesis. Here, we developed an in vivo neonatal mouse model that recapitulates key aspects of echovirus-induced meningitis. We show that expression of the human homologue of the primary echovirus receptor, the neonatal Fc receptor (FcRn), is not sufficient for infection of the brains of neonatal mice. However, ablation of type I, but not III, interferon (IFN) signaling in mice expressing human FcRn permitted high levels of echovirus replication in the brain, with corresponding clinical symptoms, including delayed motor skills and hind-limb weakness. Using this model, we defined the immunological response of the brain to echovirus infection and identified key cytokines, such as granulocyte colony-stimulating factor (G-CSF) and interleukin 6 (IL-6), that were induced by this infection. Lastly, we showed that echoviruses specifically replicate in the leptomeninges, where they induce profound inflammation and cell death. Together, this work establishes an in vivo model of aseptic meningitis associated with echovirus infections that delineates the differential roles of type I and type III IFNs in echovirus-associated neuronal disease and defines the specificity of echoviral infections within the meninges. IMPORTANCE Echoviruses are among the most common worldwide causes of aseptic meningitis, which can cause long-term sequelae or even death. The mechanisms by which echoviruses infect the brain are poorly understood, largely owing to the lack of robust in vivo models that recapitulate this aspect of echovirus pathogenesis. Here, we establish a neonatal mouse model of echovirus-induced aseptic meningitis and show that expression of the human homologue of the FcRn, the primary receptor for echoviruses, and ablation of type I IFN signaling are required to recapitulate echovirus-induced meningitis and clinical disease. These findings provide key insights into the host factors that control echovirus-induced meningitis and a model that could be used to test anti-echovirus therapeutics.


Assuntos
Infecções do Sistema Nervoso Central , Infecções por Echovirus , Meningite Asséptica , Animais , Infecções do Sistema Nervoso Central/fisiopatologia , Infecções do Sistema Nervoso Central/virologia , Infecções por Echovirus/complicações , Infecções por Echovirus/fisiopatologia , Infecções por Echovirus/virologia , Enterovirus Humano B/fisiologia , Humanos , Inflamação , Interferon Tipo I/metabolismo , Interferons , Meningite Asséptica/etiologia , Meningite Asséptica/fisiopatologia , Meningite Asséptica/virologia , Camundongos , Interferon lambda
8.
mBio ; 13(3): e0044322, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35604122

RESUMO

Enteroviruses are among the most common viral infectious agents of humans and cause a broad spectrum of mild-to-severe illness. Enteroviruses are transmitted primarily by the fecal-oral route, but the events associated with their intestinal replication in vivo are poorly defined. Here, we developed a neonatal mouse model of enterovirus infection by the enteral route using echovirus 5 and used this model to define the differential roles of type I and III interferons (IFNs) in enterovirus replication in the intestinal epithelium and subsequent dissemination to secondary tissues. We show that human neonatal Fc receptor (FcRn), the primary receptor for echoviruses, is essential for intestinal infection by the enteral route and that type I IFNs control dissemination to secondary sites, including the liver. In contrast, type III IFNs limit echovirus infection in the intestinal epithelium, and mice lacking this pathway exhibit extended epithelial replication. Finally, we show that echovirus infection in the small intestine is cell type specific and occurs exclusively in enterocytes. These studies define the type-specific roles of IFNs in enterovirus infection of the gastrointestinal (GI) tract and the cellular tropism of echovirus replication in the intestinal epithelium. IMPORTANCE Echovirus infections are associated with a broad spectrum of illness, particularly in neonates, and are primarily transmitted through the fecal-oral route. Little is known regarding how echoviruses infect the gastrointestinal tract and how the intestinal epithelium controls echoviral replication. Here, we establish an in vivo mouse model of echovirus infection by the enteral route and define the differential roles of type I and III interferons (IFNs) in controlling viral replication in the intestine. These findings provide important insights into the mechanisms by which echoviruses infect the GI tract and the epithelium-specific antiviral pathways that control this infection.


Assuntos
Infecções por Echovirus , Infecções por Enterovirus , Enterovirus , Trato Gastrointestinal , Interferon Tipo I , Animais , Infecções por Echovirus/metabolismo , Enterovirus Humano B , Interferon Tipo I/metabolismo , Interferons/metabolismo , Mucosa Intestinal/metabolismo , Camundongos , Replicação Viral
9.
J Community Psychol ; 49(8): 3162-3177, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34766632

RESUMO

Culture shapes and animates how community organizing is understood and carried out in specific contexts. Many frameworks for examining organizing, however, do not effectively attend to the influences of culture. Greater understanding of how culture can be imbued in organizing can help to ground it in the social realities of organizing participants and can advance approaches to organizing that honor the past and present of specific cultures. This study details local culturally grounded community organizing work rooted in Indigenous, and specifically Menominee, culture. First, it provides a description of the formation of the organization Menikanaehkem in the Menominee Nation and includes examples of how current organizing practices of Menikanaehkem build from long-standing Menominee cultural practices. It then highlights the reinvigoration of cultural practices, or re-indigenization, as an important goal for community power building in Menikanaehkem. It ends with a discussion of the importance of culture in frameworks for understanding, analyzing, and promoting organizing as an endeavor to advance well-being in a way that also interrupts cycles of structural oppression, such as legacies of settler colonialism.


Assuntos
Colonialismo , Grupos Populacionais , Humanos
10.
Elife ; 102021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34196272

RESUMO

Enterovirus D68 (EV-D68) has been implicated in outbreaks of severe respiratory illness and is associated with acute flaccid myelitis (AFM). EV-D68 is often detected in patient respiratory samples but has also been detected in stool and wastewater, suggesting the potential for both respiratory and enteric routes of transmission. Here, we used a panel of EV-D68 isolates, including a historical pre-2014 isolate and multiple contemporary isolates from AFM outbreak years, to define the dynamics of viral replication and the host response to infection in primary human airway cells and stem cell-derived enteroids. We show that some recent EV-D68 isolates have decreased sensitivity to acid and temperature compared with earlier isolates and that the respiratory, but not intestinal, epithelium induces a robust type III interferon response that restricts infection. Our findings define the differential responses of the respiratory and intestinal epithelium to contemporary EV-D68 isolates and suggest that a subset of isolates have the potential to target both the human airway and gastrointestinal tracts.


Assuntos
Enterovirus Humano D/classificação , Células Epiteliais/fisiologia , Células Epiteliais/virologia , Linhagem Celular , Enterovirus Humano D/genética , Células Epiteliais/imunologia , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Intestinos/citologia , Pulmão/citologia , Organoides , Temperatura
11.
Immunity ; 54(6): 1102-1104, 2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34107267

RESUMO

The impact of inhibitory receptor NKG2A-mediated education on uterine NK (uNK) cell responsiveness to vascular remodeling on pregnancy outcomes has remained unclear. In this issue of Immunity, Shreeve et al. show that loss of NKG2A+ uNK cells results in deficient vascularization and restricted fetal growth.


Assuntos
Células Matadoras Naturais , Útero , Feminino , Humanos , Neovascularização Patológica , Gravidez , Remodelação Vascular
12.
PLoS Pathog ; 17(1): e1009252, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33513208

RESUMO

Neonatal echovirus infections are characterized by severe hepatitis and neurological complications that can be fatal. Here, we show that expression of the human homologue of the neonatal Fc receptor (hFcRn), the primary receptor for echoviruses, and ablation of type I interferon (IFN) signaling are key host determinants involved in echovirus pathogenesis. We show that expression of hFcRn alone is insufficient to confer susceptibility to echovirus infections in mice. However, expression of hFcRn in mice deficient in type I interferon (IFN) signaling, hFcRn-IFNAR-/-, recapitulate the echovirus pathogenesis observed in humans. Luminex-based multianalyte profiling from E11 infected hFcRn-IFNAR-/- mice revealed a robust systemic immune response to infection, including the induction of type I IFNs. Furthermore, similar to the severe hepatitis observed in humans, E11 infection in hFcRn-IFNAR-/- mice caused profound liver damage. Our findings define the host factors involved in echovirus pathogenesis and establish in vivo models that recapitulate echovirus disease in humans.


Assuntos
Enterovirus Humano B/patogenicidade , Infecções por Enterovirus/virologia , Genoma Viral/genética , Hepatite/virologia , Antígenos de Histocompatibilidade Classe I/metabolismo , Interferon Tipo I/metabolismo , Receptores Fc/metabolismo , Transdução de Sinais , Animais , Enterovirus Humano B/genética , Infecções por Enterovirus/imunologia , Feminino , Expressão Gênica , Hepatite/imunologia , Hepatócitos/imunologia , Hepatócitos/virologia , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Imunidade , Fígado/imunologia , Fígado/virologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores Fc/genética
13.
J Clin Aesthet Dermatol ; 13(4): 43-44, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33144911

RESUMO

There is a shortage of dermatologists available to see hospitalized patients, especially for urgent evaluations such as in the emergency department setting. The use of teledermatology in the emergency setting was studied for patients presenting to the emergency department with symptoms of or a diagnosis of cellulitis. Thirty patients were enrolled and randomized to a teledermatology note being placed in their chart versus control patients undergoing standard care. Although randomized, in this small pilot study, the locations of involvement were unbalanced across treatment groups. The mean length of stay was slightly longer in the group randomized to teledermatology; however, this was largely related to the unbalanced number of patients presenting with bilateral and lower extremity complaints in the teledermatology group. This study provides important preliminary data for future studies, including ensuring appropriate balancing of locations of involvement, a larger sample size, and more rigid entry criteria.

15.
Ann Biomed Eng ; 48(3): 1058-1070, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31367915

RESUMO

Loss of ovarian function (e.g., due to menopause) leads to profound physiological effects in women including changes in sexual function and osteoporosis. Hormone therapies are a known solution, but their use has significantly decreased due to concerns over cardiovascular disease and certain cancers. We recently reported a tissue-engineering strategy for cell hormone therapy (cHT) in which granulosa cells and theca cells are encapsulated to mimic native ovarian follicles. cHT improved physiological outcomes and safety compared to pharmacological hormone therapies in a rat ovariectomy model. However, cHT did not achieve estrogen levels as high as ovary-intact animals. In this report, we examined if hormone secretion from cHT constructs is impacted by incorporation of bone marrow-derived mesenchymal stem cells (BMSC) since these cells contain regulatory factors such as aromatase necessary for estrogen production. Incorporation of BMSCs led to enhanced estrogen secretion in vitro. Moreover, cHT constructs with BMSCs achieved estrogen secretion levels significantly greater than constructs without BMSCs in ovariectomized rats from 70 to 90 days after implantation, while also regulating pituitary hormones. cHT constructs with BMSC ameliorated estrogen deficiency-induced uterine atrophy without hyperplasia. The results indicate that inclusion of BMSC in cHT strategies can improve performance.


Assuntos
Terapia Baseada em Transplante de Células e Tecidos , Estrogênios/metabolismo , Células da Granulosa/metabolismo , Terapia de Reposição Hormonal , Células-Tronco Mesenquimais/metabolismo , Células Tecais/metabolismo , Engenharia Tecidual , Animais , Aromatase/metabolismo , Células Cultivadas , Feminino , Hormônio Foliculoestimulante/metabolismo , Hormônio Luteinizante/metabolismo , Ovariectomia , Progesterona/metabolismo , Ratos Endogâmicos F344 , Útero/anatomia & histologia
16.
Health Educ Behav ; 46(1_suppl): 81S-87S, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31549556

RESUMO

Recent perspectives on Indigenous health have recognized language, culture, and values as central to well-being and recovery from historical trauma. Health coalitions, which identify community health concerns and mobilize members to implement strategies for change, have begun to shift their focus from programs to policy, systems, and environmental change but have been slower to recognize the possibilities of centering Indigenous ways of being in their work. This article details a case study of the Menominee Wellness Initiative, an Indigenous health coalition that has increasingly made language, culture, and collective values the focus of their health promotion work, and often due to the participation and influence of community organizers in the coalition. The study is presented as a collaborative writing effort between coalition members and academic partners. Qualitative data were gathered through observations of coalition meetings; in-depth, semistructured interviews with coalition members; and interactive data analysis discussions within the collaborative writing team. In the results, we describe how the shift in the coalition's framework came to be and the influence this shift has had on the coalition, its activities, and its community impacts. These findings illustrate and extend understanding of several principles of Collaborating for Equity and Justice and supports literature and practice related to health promotion through the centering of Indigenous ways.


Assuntos
Participação da Comunidade/métodos , Promoção da Saúde/organização & administração , Saúde Holística/etnologia , Indígenas Norte-Americanos , Idioma , Relações Comunidade-Instituição , Comportamento Cooperativo , Características Culturais , Humanos , Universidades/organização & administração , Wisconsin
17.
Viruses ; 11(5)2019 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-31117206

RESUMO

Enteroviruses are a major source of human disease, particularly in neonates and young children where infections can range from acute, self-limited febrile illness to meningitis, endocarditis, hepatitis, and acute flaccid myelitis. The enterovirus genus includes poliovirus, coxsackieviruses, echoviruses, enterovirus 71, and enterovirus D68. Enteroviruses primarily infect by the fecal-oral route and target the gastrointestinal epithelium early during their life cycles. In addition, spread via the respiratory tract is possible and some enteroviruses such as enterovirus D68 are preferentially spread via this route. Once internalized, enteroviruses are detected by intracellular proteins that recognize common viral features and trigger antiviral innate immune signaling. However, co-evolution of enteroviruses with humans has allowed them to develop strategies to evade detection or disrupt signaling. In this review, we will discuss how enteroviruses infect the gastrointestinal tract, the mechanisms by which cells detect enterovirus infections, and the strategies enteroviruses use to escape this detection.


Assuntos
Infecções por Enterovirus/virologia , Enterovirus/fisiologia , Interações Hospedeiro-Patógeno , Animais , Biomarcadores , Infecções por Enterovirus/diagnóstico , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/transmissão , Microbioma Gastrointestinal , Interações Hospedeiro-Patógeno/imunologia , Humanos , Evasão da Resposta Imune , Imunidade Inata , Receptores de Reconhecimento de Padrão/metabolismo , Internalização do Vírus
18.
Sci Adv ; 5(3): eaau4255, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30854425

RESUMO

Recent worldwide outbreaks of enterovirus 71 (EV71) have caused major epidemics of hand, foot, and mouth disease with severe neurological complications, including acute flaccid paralysis. EV71 is transmitted by the enteral route, but little is known about the mechanisms it uses to cross the human gastrointestinal tract. Using primary human intestinal epithelial monolayers, we show that EV71 infects the epithelium from the apical surface, where it preferentially infects goblet cells. We found that EV71 infection did not alter epithelial barrier function but did reduce the expression of goblet cell-derived mucins, suggesting that it alters goblet cell function. We also show that the intestinal epithelium responds to EV71 infection through the selective induction of type III interferons (IFNs), which restrict EV71 replication. Collectively, these findings define the early events associated with EV71 infections of the human intestinal epithelium and show that host IFN signaling controls replication in an IFN-specific manner.


Assuntos
Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Células Caliciformes/metabolismo , Células Caliciformes/virologia , Interações Hospedeiro-Patógeno , Interferons/metabolismo , Transdução de Sinais , Permeabilidade da Membrana Celular , Células Cultivadas , Imunofluorescência , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/virologia , Interferon lambda
19.
Proc Natl Acad Sci U S A ; 116(9): 3758-3763, 2019 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-30808762

RESUMO

Echoviruses are amongst the most common causative agents of aseptic meningitis worldwide and are particularly devastating in the neonatal population, where they are associated with severe hepatitis, neurological disease, including meningitis and encephalitis, and even death. Here, we identify the neonatal Fc receptor (FcRn) as a pan-echovirus receptor. We show that loss of expression of FcRn or its binding partner beta 2 microglobulin (ß2M) renders cells resistant to infection by a panel of echoviruses at the stage of virus attachment, and that a blocking antibody to ß2M inhibits echovirus infection in cell lines and in primary human intestinal epithelial cells. We also show that expression of human, but not mouse, FcRn renders nonpermissive human and mouse cells sensitive to echovirus infection and that the extracellular domain of human FcRn directly binds echovirus particles and neutralizes infection. Lastly, we show that neonatal mice expressing human FcRn are more susceptible to echovirus infection by the enteral route. Our findings thus identify FcRn as a pan-echovirus receptor, which may explain the enhanced susceptibility of neonates to echovirus infections.


Assuntos
Enterovirus Humano B/genética , Antígenos de Histocompatibilidade Classe I/genética , Receptores Fc/genética , Receptores Virais/genética , Microglobulina beta-2/genética , Animais , Infecções por Echovirus/genética , Infecções por Echovirus/imunologia , Infecções por Echovirus/virologia , Enterovirus Humano B/patogenicidade , Humanos , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Camundongos , Ligação Proteica , Microglobulina beta-2/imunologia
20.
mBio ; 9(6)2018 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-30538178

RESUMO

The human immunodeficiency virus type 1 (HIV-1) envelope (Env) trimer evades antibody recognition by adopting a closed prefusion conformation. Here, we show that two conserved tyrosines (Y173, Y177) within the second variable (V2) loop of the gp120 Env glycoprotein are key regulators of the closed, antibody-protected state of the trimer by establishing intramolecular interaction with the base of the third variable (V3) loop. Mutation of Y177 and/or Y173 to phenylalanine or alanine dramatically altered the susceptibility of diverse HIV-1 strains to neutralization, increasing sensitivity to weakly and nonneutralizing antibodies directed against diverse Env regions, consistent with the adoption of an open trimer configuration. Conversely, potent broadly neutralizing antibodies (bNAbs) against different supersites of HIV-1 vulnerability exhibited reduced potency against V2 loop tyrosine mutants, consistent with their preferential targeting of the closed trimer. Mutation of V3 loop residues predicted to interact with the V2 loop tyrosines yielded a similar neutralization phenotype. Sera from chronically HIV-1-infected patients contained very high titers of antibodies capable of neutralizing V2 loop tyrosine mutants but not wild-type viruses, indicating that the bulk of antibodies produced in infected hosts are unable to penetrate the protective shield of the closed trimer. These results identify the tyrosine-mediated V2-V3 loop complex at the trimer apex as a key structural constraint that facilitates HIV-1 evasion from the bulk of host antibodies.IMPORTANCE The extraordinary ability of human immunodeficiency virus type 1 (HIV-1) to evade host immunity represents a major obstacle to the development of a protective vaccine. Thus, elucidating the mechanisms whereby HIV-1 protects its external envelope (Env), which is the sole target of virus-neutralizing antibodies, is an essential step toward vaccine design. We identified a key structural element that maintains the HIV-1 Env trimer in a closed, antibody-resistant conformation. A major role is played by two conserved tyrosines at the apex of the Env spike, whose mutation causes a global opening of the trimer structure, exposing multiple concealed targets for neutralizing antibodies. We also found that HIV-infected individuals produce very large amounts of antibodies that neutralize the open Env form; however, the bulk of these antibodies are unable to penetrate the tight defensive shield of the native virus. This work may help to devise new strategies to overcome the viral defensive mechanisms and facilitate the development of an effective HIV-1 vaccine.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , HIV-1/imunologia , Análise Mutacional de DNA , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/genética , Infecções por HIV/imunologia , HIV-1/genética , Humanos , Evasão da Resposta Imune , Testes de Neutralização , Estrutura Quaternária de Proteína
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