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Muscle fatigue represents the most prevalent symptom of long-term COVID, with elusive pathogenic mechanisms. We performed a longitudinal study to characterize histopathological and transcriptional changes in skeletal muscle in a hamster model of respiratory SARS-CoV-2 infection and compared them with influenza A virus (IAV) and mock infections. Histopathological and bulk RNA sequencing analyses of leg muscles derived from infected animals at days 3, 30, and 60 post-infection showed no direct viral invasion but myofiber atrophy in the SARS-CoV-2 group, which was accompanied by persistent downregulation of the genes related to myofibers, ribosomal proteins, fatty acid ß-oxidation, tricarboxylic acid cycle, and mitochondrial oxidative phosphorylation complexes. While both SARS-CoV-2 and IAV infections induced acute and transient type I and II interferon responses in muscle, only the SARS-CoV-2 infection upregulated TNF-α/NF-κB but not IL-6 signaling in muscle. Treatment of C2C12 myotubes, a skeletal muscle cell line, with combined IFN-γ and TNF-α but not with IFN-γ or TNF-α alone markedly impaired mitochondrial function. We conclude that a respiratory SARS-CoV-2 infection can cause myofiber atrophy and persistent energy metabolism suppression without direct viral invasion. The effects may be induced by the combined systemic interferon and TNF-α responses at the acute phase and may contribute to post-COVID-19 persistent muscle fatigue.
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COVID-19 , Vírus da Influenza A , Animais , Cricetinae , Humanos , SARS-CoV-2 , Perfilação da Expressão Gênica , Medula EspinalRESUMO
OBJECTIVE: The purpose of the article is to evaluate an innovative education program in which medical students were trained in cognitive behavior therapy (CBT) and provided CBT treatments under supervision to uninsured individuals with depressive, anxiety, adjustment, and trauma-based disorders. METHODS: The authors assessed improvements in trainees' CBT knowledge using the Cognitive Therapy Awareness Scale before and after their didactic training. CBT supervisors rated trainees' clinical competencies utilizing standardized checklist evaluations based upon supervision reports. The authors employed mixed effects ANOVA and regression modeling to test the association between the addition of CBT to treatment as usual (TAU) and improvements in patients' depressive and anxious symptom severity. The authors collected feedback and self-assessment of functioning with a Psychotherapy Feedback Questionnaire. RESULTS: Medical students showed increases in CBT knowledge that were maintained six months later and demonstrated satisfactory competency in CBT techniques. The addition of CBT to TAU was associated with greater improvements in depressive, but not anxious, symptom severity. However, among the TAU + CBT group, there was an association between the number of CBT sessions received and the magnitude of improvement in anxious symptoms from baseline. Patients gave positive feedback to medical student CBT providers and reported improvements in broad domains of psychosocial functioning. CONCLUSIONS: Medical students can provide competent and clinically beneficial CBT treatments for depression and anxiety disorders. These findings have implications for medical training and support the use of medical students to deliver care for individuals with limited access to psychotherapy.
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Terapia Cognitivo-Comportamental , Estudantes de Medicina , Humanos , Depressão/terapia , Terapia Cognitivo-Comportamental/métodos , Transtornos de Ansiedade/terapia , Psicoterapia , Ansiedade , Resultado do TratamentoRESUMO
Clinical presentations that develop in response to infection result from interactions between the pathogen and host defenses. SARS-CoV-2, the etiologic agent of COVID-19, directly antagonizes these defenses, leading to delayed immune engagement in the lungs that materializes only as cells succumb to infection and are phagocytosed. Leveraging the golden hamster model of COVID-19, we sought to understand the dynamics between SARS-CoV-2 infection in the airways and the systemic host response that ensues. We found that early SARS-CoV-2 replication was largely confined to the respiratory tract and olfactory system and, to a lesser extent, the heart and gastrointestinal tract but generated a host antiviral response in every organ as a result of circulating type I and III interferons. Moreover, we showed that diminishing the response in the airways by immunosuppression or administration of SARS-CoV-2 intravenously resulted in decreased immune priming, viremia, and increased viral tropism, including productive infection of the liver, kidney, spleen, and brain. Last, we showed that productive infection of the airways was required for mounting an effective and system-wide antiviral response. Together, these data illustrate how COVID-19 can result in diverse clinical presentations in which disease outcomes can be a by-product of the speed and strength of immune engagement. These studies provide additional evidence for the mechanistic basis of the diverse clinical presentations of COVID-19 and highlight the ability of the respiratory tract to generate a systemic immune defense after pathogen recognition.
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COVID-19 , Animais , Cricetinae , SARS-CoV-2 , Viremia , Antivirais , EncéfaloRESUMO
Although largely confined to the airways, SARS-CoV-2 infection has been associated with sensory abnormalities that manifest in both acute and chronic phenotypes. To gain insight on the molecular basis of these sensory abnormalities, we used the golden hamster model to characterize and compare the effects of infection with SARS-CoV-2 and influenza A virus (IAV) on the sensory nervous system. We detected SARS-CoV-2 transcripts but no infectious material in the cervical and thoracic spinal cord and dorsal root ganglia (DRGs) within the first 24 hours of intranasal virus infection. SARS-CoV-2-infected hamsters exhibited mechanical hypersensitivity that was milder but prolonged compared with that observed in IAV-infected hamsters. RNA sequencing analysis of thoracic DRGs 1 to 4 days after infection suggested perturbations in predominantly neuronal signaling in SARS-CoV-2-infected animals as opposed to type I interferon signaling in IAV-infected animals. Later, 31 days after infection, a neuropathic transcriptome emerged in thoracic DRGs from SARS-CoV-2-infected animals, which coincided with SARS-CoV-2-specific mechanical hypersensitivity. These data revealed potential targets for pain management, including the RNA binding protein ILF3, which was validated in murine pain models. This work elucidates transcriptomic signatures in the DRGs triggered by SARS-CoV-2 that may underlie both short- and long-term sensory abnormalities.
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COVID-19 , Vírus da Influenza A , Cricetinae , Animais , Camundongos , COVID-19/genética , SARS-CoV-2 , Gânglios Espinais , Perfilação da Expressão GênicaRESUMO
Viruses constantly evolve and adapt to the antiviral defenses of their hosts. The biology of viral circumvention of these selective pressures can often be attributed to the acquisition of novel antagonistic gene products or by rapid genome change that prevents host recognition. To study viral evasion of RNA interference (RNAi)-based defenses, we established a robust antiviral system in mammalian cells using recombinant Sendai virus designed to be targeted by endogenous host microRNAs (miRNAs) with perfect complementarity. Using this system, we previously demonstrated the intrinsic ability of positive-strand RNA viruses to escape this selective pressure via homologous recombination, which was not observed in negative-strand RNA viruses. Here, we show that given extensive time, escape of miRNA-targeted Sendai virus was enabled by host adenosine deaminase acting on RNA 1 (ADAR1). Independent of the viral transcript targeted, ADAR1 editing resulted in disruption of the miRNA-silencing motif, suggesting an intolerance for extensive RNA-RNA interactions necessary for antiviral RNAi. This was further supported in Nicotiana benthamiana, where exogenous expression of ADAR1 interfered with endogenous RNAi. Together, these results suggest that ADAR1 diminishes the effectiveness of RNAi and may explain why it is absent in species that utilize this antiviral defense system. IMPORTANCE All life at the cellular level has the capacity to induce an antiviral response. Here, we examine the result of imposing the antiviral response of one branch of life onto another and find evidence for conflict. To determine the consequences of eliciting an RNAi-like defense in mammals, we applied this pressure to a recombinant Sendai virus in cell culture. We find that ADAR1, a host gene involved in regulation of the mammalian response to virus, prevented RNAi-mediated silencing and subsequently allowed for viral replication. In addition, the expression of ADAR1 in Nicotiana benthamiana, which lacks ADARs and has an endogenous RNAi system, suppresses gene silencing. These data indicate that ADAR1 is disruptive to RNAi biology and provide insight into the evolutionary relationship between ADARs and antiviral defenses in eukaryotic life.
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Adenosina Desaminase , Interações entre Hospedeiro e Microrganismos , MicroRNAs , Interferência de RNA , Infecções por Respirovirus , Animais , Adenosina Desaminase/genética , Adenosina Desaminase/metabolismo , Antivirais/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Replicação Viral/genética , Vírus Sendai/classificação , Inativação Gênica , Humanos , Mutação , Fases de Leitura Aberta , Evolução Biológica , Interações entre Hospedeiro e Microrganismos/genética , Infecções por Respirovirus/metabolismo , Infecções por Respirovirus/virologiaRESUMO
Viruses infect millions of people each year. Both endemic viruses circulating throughout the population as well as novel epidemic and pandemic viruses pose ongoing threats to global public health. Developing more effective tools to address viruses requires not only in-depth knowledge of the virus itself but also of our immune system's response to infection. On June 29 to July 2, 2022, researchers met for the Keystone symposium "Viral Immunity: Basic Mechanisms and Therapeutic Applications." This report presents concise summaries from several of the symposium presenters.
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Influenza Humana , Pandemias , Humanos , Influenza Humana/epidemiologiaRESUMO
Despite being largely confined to the airways, SARS-CoV-2 infection has been associated with sensory abnormalities that manifest in both acute and long-lasting phenotypes. To gain insight on the molecular basis of these sensory abnormalities, we used the golden hamster infection model to characterize the effects of SARS-CoV-2 versus Influenza A virus (IAV) infection on the sensory nervous system. Efforts to detect the presence of virus in the cervical/thoracic spinal cord and dorsal root ganglia (DRGs) demonstrated detectable levels of SARS-CoV-2 by quantitative PCR and RNAscope uniquely within the first 24 hours of infection. SARS-CoV-2-infected hamsters demonstrated mechanical hypersensitivity during acute infection; intriguingly, this hypersensitivity was milder, but prolonged when compared to IAV-infected hamsters. RNA sequencing (RNA-seq) of thoracic DRGs from acute infection revealed predominantly neuron-biased signaling perturbations in SARS-CoV-2-infected animals as opposed to type I interferon signaling in tissue derived from IAV-infected animals. RNA-seq of 31dpi thoracic DRGs from SARS-CoV-2-infected animals highlighted a uniquely neuropathic transcriptomic landscape, which was consistent with substantial SARS-CoV-2-specific mechanical hypersensitivity at 28dpi. Ontology analysis of 1, 4, and 30dpi RNA-seq revealed novel targets for pain management, such as ILF3. Meta-analysis of all SARS-CoV-2 RNA-seq timepoints against preclinical pain model datasets highlighted both conserved and unique pro-nociceptive gene expression changes following infection. Overall, this work elucidates novel transcriptomic signatures triggered by SARS-CoV-2 that may underlie both short- and long-term sensory abnormalities while also highlighting several therapeutic targets for alleviation of infection-induced hypersensitivity. One Sentence Summary: SARS-CoV-2 infection results in an interferon-associated transcriptional response in sensory tissues underlying time-dependent hypersensitivity.
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The host response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection can result in prolonged pathologies collectively referred to as post-acute sequalae of COVID-19 (PASC) or long COVID. To better understand the mechanism underlying long COVID biology, we compared the short- and long-term systemic responses in the golden hamster after either SARS-CoV-2 or influenza A virus (IAV) infection. Results demonstrated that SARS-CoV-2 exceeded IAV in its capacity to cause permanent injury to the lung and kidney and uniquely affected the olfactory bulb (OB) and olfactory epithelium (OE). Despite a lack of detectable infectious virus, the OB and OE demonstrated myeloid and T cell activation, proinflammatory cytokine production, and an interferon response that correlated with behavioral changes extending a month after viral clearance. These sustained transcriptional changes could also be corroborated from tissue isolated from individuals who recovered from COVID-19. These data highlight a molecular mechanism for persistent COVID-19 symptomology and provide a small animal model to explore future therapeutics.
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COVID-19 , Animais , COVID-19/complicações , Cricetinae , Humanos , Interferons , Mesocricetus , SARS-CoV-2 , Síndrome de COVID-19 Pós-AgudaRESUMO
Aging is associated with functional deficits in the naive T cell compartment, which compromise the generation of de novo immune responses against previously unencountered Ags. The mechanisms that underlie this phenomenon have nonetheless remained unclear. We found that naive CD8+ T cells in elderly humans were prone to apoptosis and proliferated suboptimally in response to stimulation via the TCR. These abnormalities were associated with dysregulated lipid metabolism under homeostatic conditions and enhanced levels of basal activation. Importantly, reversal of the bioenergetic anomalies with lipid-altering drugs, such as rosiglitazone, almost completely restored the Ag responsiveness of naive CD8+ T cells. Interventions that favor lipid catabolism may therefore find utility as adjunctive therapies in the elderly to promote vaccine-induced immunity against targetable cancers and emerging pathogens, such as seasonal influenza viruses and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).
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Envelhecimento/imunologia , Linfócitos T CD8-Positivos/imunologia , Imunocompetência/efeitos dos fármacos , Metabolismo dos Lipídeos , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Linfócitos T CD8-Positivos/metabolismo , COVID-19/imunologia , Vacinas Anticâncer/imunologia , Divisão Celular , Feminino , Fenofibrato/farmacologia , Glucose/metabolismo , Antígeno HLA-A2/imunologia , Humanos , Hipolipemiantes/farmacologia , Hipolipemiantes/uso terapêutico , Influenza Humana/imunologia , Metabolismo dos Lipídeos/efeitos dos fármacos , Ativação Linfocitária , Antígeno MART-1/química , Antígeno MART-1/imunologia , Masculino , Pessoa de Meia-Idade , Neoplasias/imunologia , Fragmentos de Peptídeos/imunologia , Rosiglitazona/farmacologia , Método Simples-Cego , Vacinação , Vacinas Virais/imunologia , Adulto JovemRESUMO
Undocumented immigrants have disproportionately suffered during the novel coronavirus disease 2019 (COVID-19) pandemic due to factors including limited medical access and financial insecurity, which can exacerbate pandemic-associated distress. Psychological outcomes for immigrant outpatients were assessed after transition to telepsychiatry in March 2020. Mental health was assessed with Patient Health Questionnaire (PHQ-2) and Generalized Anxiety Disorder (GAD-2) inventories, a novel coronavirus-specific survey, and the Kessler Psychological Distress Scale (K10+). Feedback on telepsychiatry sessions and access to non-clinical resources were also gathered, after which multivariable linear regression modeling identified psychosocial factors underlying changes in distress levels. 48.57% and 45.71% of participants reported worsened anxiety and depression levels due to the pandemic, respectively. From March to April, PHQ-2 and GAD-2 scores significantly increased by 0.81 and 0.63 points, respectively. The average total psychological distress score was 23.8, with 60% of scores reflecting serious mental illness. Factors that most influenced K10+ scores included a pre-existing depressive disorder, food insecurity, and comfort during telepsychiatry visits. 93.75% of participants believed access to remote psychiatry helped their mental health during COVID-19. The negative impact of COVID-19 on mental health in vulnerable populations stems from medical and psychosocial factors such as pre-existing psychiatric conditions and unmet essential needs.
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Ansiedade/epidemiologia , COVID-19 , Depressão/epidemiologia , Emigrantes e Imigrantes/estatística & dados numéricos , Serviços de Saúde Mental/estatística & dados numéricos , Pacientes Ambulatoriais/estatística & dados numéricos , Angústia Psicológica , Estresse Psicológico/epidemiologia , Telemedicina/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The inflammatory responses in chronic airway diseases leading to emphysema are not fully defined. We hypothesised that lung eosinophilia contributes to airspace enlargement in a mouse model and to emphysema in patients with chronic obstructive pulmonary disease (COPD).A transgenic mouse model of chronic type 2 pulmonary inflammation (I5/hE2) was used to examine eosinophil-dependent mechanisms leading to airspace enlargement. Human sputum samples were collected for translational studies examining eosinophilia and matrix metalloprotease (MMP)-12 levels in patients with chronic airways disease.Airspace enlargement was identified in I5/hE2 mice and was dependent on eosinophils. Examination of I5/hE2 bronchoalveolar lavage identified elevated MMP-12, a mediator of emphysema. We showed, in vitro, that eosinophil-derived interleukin (IL)-13 promoted alveolar macrophage MMP-12 production. Airspace enlargement in I5/hE2 mice was dependent on MMP-12 and eosinophil-derived IL-4/13. Consistent with this, MMP-12 was elevated in patients with sputum eosinophilia and computed tomography evidence of emphysema, and also negatively correlated with forced expiratory volume in 1â s.A mouse model of chronic type 2 pulmonary inflammation exhibited airspace enlargement dependent on MMP-12 and eosinophil-derived IL-4/13. In chronic airways disease patients, lung eosinophilia was associated with elevated MMP-12 levels, which was a predictor of emphysema. These findings suggest an underappreciated mechanism by which eosinophils contribute to the pathologies associated with asthma and COPD.
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Eosinófilos/imunologia , Interleucina-13/imunologia , Pneumonia/etiologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Enfisema Pulmonar/etiologia , Idoso , Animais , Asma/imunologia , Asma/patologia , Modelos Animais de Doenças , Eosinófilos/patologia , Feminino , Humanos , Interleucina-4/imunologia , Macrófagos Alveolares/patologia , Masculino , Metaloproteinase 12 da Matriz/imunologia , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Análise Multivariada , Pneumonia/imunologia , Pneumonia/patologia , Doença Pulmonar Obstrutiva Crônica/imunologia , Doença Pulmonar Obstrutiva Crônica/patologia , Enfisema Pulmonar/imunologia , Enfisema Pulmonar/patologia , Análise de Regressão , Sistema Respiratório/fisiopatologiaRESUMO
Zika virus (ZIKV) has recently been associated with birth defects and pregnancy loss after maternal infection. Because dengue virus (DENV) and ZIKV co-circulate, understanding the role of antibody-dependent enhancement in the context of pregnancy is critical. Here, we showed that the presence of DENV-specific antibodies in ZIKV-infected pregnant mice significantly increased placental damage, fetal growth restriction, and fetal resorption. This was associated with enhanced viral replication in the placenta that coincided with an increased frequency of infected trophoblasts. ZIKV-infected human placental tissues also showed increased replication in the presence of DENV antibodies, which was reversed by FcγR blocking antibodies. Furthermore, ZIKV-mediated fetal pathogenesis was enhanced in mice in the presence of a DENV-reactive monoclonal antibody, but not in the presence of the LALA variant, indicating a dependence on FcγR engagement. Our data suggest a possible mechanism for the recent increase in severe pregnancy outcomes after ZIKV infection in DENV-endemic areas.
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Vírus da Dengue/imunologia , Imunidade/imunologia , Infecção por Zika virus/imunologia , Zika virus/imunologia , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Anticorpos Facilitadores/imunologia , Linhagem Celular Tumoral , Chlorocebus aethiops , Reações Cruzadas/imunologia , Feminino , Humanos , Células K562 , Camundongos , Gravidez , Células VeroRESUMO
Background: Characterization of the intracellular biochemical processes that regulate the generation and maintenance of effector and memory CD8+ T-cells from naïve precursors is essential for our understanding of adaptive immune responses and the development of immunotherapies. However, the metabolic determinants of antigen-driven activation and differentiation remain poorly defined, especially in humans. Methods: We used a variety of different approaches, including gene expression profiling and measurements of nutrient flux, to characterize the basal and activation-induced energetic requirements of naïve and phenotypically-defined subsets of human memory CD8+ T-cells. Findings: Profound metabolic differences were apparent as a function of differentiation status, both at rest and in response to stimulation via the T cell receptor (TCR). Of particular note, resting naïve CD8+ T cells were largely quiescent, but rapidly upregulated diverse energetic pathways after ligation of surface-expressed TCRs. Moreover, autophagy and the mechanistic target of rapamycin (mTOR)-dependent glycolytic pathway were identified as critical mediators of antigen-driven priming in the naïve CD8+ T cell pool, the efficiency of which was dampened by the presence of neutral lipids and fatty acids. Interpretation: These observations provide a metabolic roadmap of the CD8+ T-cell compartment in humans and reveal potentially selective targets for novel immunotherapies.
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Autofagia/imunologia , Linfócitos T CD8-Positivos , Glicólise/imunologia , Memória Imunológica , Ativação Linfocitária , Adulto , Idoso , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Serina-Treonina Quinases TOR/imunologia , Serina-Treonina Quinases TOR/metabolismoRESUMO
Zika virus (ZIKV) is spreading rapidly into regions around the world where other flaviviruses, such as dengue virus (DENV) and West Nile virus (WNV), are endemic. Antibody-dependent enhancement has been implicated in more severe forms of flavivirus disease, but whether this also applies to ZIKV infection is unclear. Using convalescent plasma from DENV- and WNV-infected individuals, we found substantial enhancement of ZIKV infection in vitro that was mediated through immunoglobulin G engagement of Fcγ receptors. Administration of DENV- or WNV-convalescent plasma into ZIKV-susceptible mice resulted in increased morbidity-including fever, viremia, and viral loads in spinal cord and testes-and increased mortality. Antibody-dependent enhancement may explain the severe disease manifestations associated with recent ZIKV outbreaks and highlights the need to exert great caution when designing flavivirus vaccines.