ABSTRACT
Human cytomegalovirus (HCMV) utilizes peripheral blood monocytes as a means to systemically disseminate throughout the host. Following viral entry, HCMV stimulates non-canonical Akt signaling leading to the activation of mTORC1 and the subsequent translation of select antiapoptotic proteins within infected monocytes. However, the full extent to which the HCMV-initiated Akt/mTORC1 signaling axis reshapes the monocyte translatome is unclear. We found HCMV entry alone was able to stimulate widescale changes to mRNA translation levels and that inhibition of mTOR, a component of mTORC1, dramatically attenuated HCMV-induced protein synthesis. Although monocytes treated with normal myeloid growth factors also exhibited increased levels of translation, mTOR inhibition had no effect, suggesting HCMV activation of mTOR stimulates the acquisition of a unique translatome within infected monocytes. Indeed, polyribosomal profiling of HCMV-infected monocytes identified distinct prosurvival transcripts that were preferentially loaded with ribosomes when compared to growth factor-treated cells. Sirtuin 1 (SIRT1), a deacetylase that exerts prosurvival effects through regulation of the PI3K/Akt pathway, was found to be highly enriched following HCMV infection in an mTOR-dependent manner. Importantly, SIRT1 inhibition led to the death of HCMV-infected monocytes while having minimal effect on uninfected cells. SIRT1 also supported a positive feedback loop to sustain Akt/mTORC1 signaling following viral entry. Taken together, HCMV profoundly reshapes mRNA translation in an mTOR-dependent manner to enhance the synthesis of select factors necessary for the survival of infected monocytes.IMPORTANCEHuman cytomegalovirus (HCMV) infection is a significant cause of morbidity and mortality among the immunonaïve and immunocompromised. Peripheral blood monocytes are a major cell type responsible for disseminating the virus from the initial site of infection. In order for monocytes to mediate viral spread within the host, HCMV must subvert the naturally short lifespan of these cells. In this study, we performed polysomal profiling analysis, which demonstrated HCMV to globally redirect mRNA translation toward the synthesis of cellular prosurvival factors within infected monocytes. Specifically, HCMV entry into monocytes induced the translation of cellular SIRT1 to generate an antiapoptotic state. Defining the precise mechanisms through which HCMV stimulates survival will provide insight into novel anti-HCMV drugs able to target infected monocytes.
Subject(s)
Cytomegalovirus , Host Microbial Interactions , Mechanistic Target of Rapamycin Complex 1 , Monocytes , Protein Biosynthesis , RNA, Messenger , Humans , Apoptosis , Cell Survival/genetics , Cytomegalovirus/growth & development , Cytomegalovirus/pathogenicity , Cytomegalovirus/physiology , Cytomegalovirus Infections/pathology , Cytomegalovirus Infections/transmission , Cytomegalovirus Infections/virology , Feedback, Physiological , Mechanistic Target of Rapamycin Complex 1/metabolism , Monocytes/cytology , Monocytes/metabolism , Monocytes/virology , Phosphatidylinositol 3-Kinases/metabolism , Polyribosomes/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Signal Transduction , Sirtuin 1/biosynthesis , Sirtuin 1/genetics , Sirtuin 1/metabolism , Virus InternalizationABSTRACT
Science is humanity's best insurance against threats from nature, but it is a fragile enterprise that must be nourished and protected. The preponderance of scientific evidence indicates a natural origin for SARS-CoV-2. Yet, the theory that SARS-CoV-2 was engineered in and escaped from a lab dominates media attention, even in the absence of strong evidence. We discuss how the resulting anti-science movement puts the research community, scientific research, and pandemic preparedness at risk.
ABSTRACT
In the United States (US), biosafety and biosecurity oversight of research on viruses is being reappraised. Safety in virology research is paramount and oversight frameworks should be reviewed periodically. Changes should be made with care, however, to avoid impeding science that is essential for rapidly reducing and responding to pandemic threats as well as addressing more common challenges caused by infectious diseases. Decades of research uniquely positioned the US to be able to respond to the COVID-19 crisis with astounding speed, delivering life-saving vaccines within a year of identifying the virus. We should embolden and empower this strength, which is a vital part of protecting the health, economy, and security of US citizens. Herein, we offer our perspectives on priorities for revised rules governing virology research in the US.
Subject(s)
Biomedical Research , Containment of Biohazards , Virology , Humans , COVID-19 , United States , Viruses , Biomedical Research/standardsABSTRACT
Australia prohibits the sale of nicotine-vaping products unless prescribed by medical practitioners. Significant policy reforms were announced on the 28th of November 2023 including a ban on single-use disposable vapes with and without nicotine, and the removal of the personal importation scheme. Despite stringent regulations, loopholes exist such that e-cigarette vendors are getting around it, and online markets provide a route to do so. We discuss strategies used by vendors to covertly market e-cigarettes online through social media. In this perspective, we highlight three proposed policies to strengthen social media regulations that may be feasible to implement. Our proposed strategies to regulate e-cigarette product listings on social media involve implementing robust age verification measures, enhancing the system for flagging and reporting prohibited content, and developing a more effective system to identify and flag content related to e-cigarettes.
Subject(s)
Advertising , Electronic Nicotine Delivery Systems , Social Media , Humans , Advertising/legislation & jurisprudence , Australia , Commerce/legislation & jurisprudence , Social Media/legislation & jurisprudence , Vaping/legislation & jurisprudenceABSTRACT
BACKGROUND AND AIMS: Electrolyte and acid-base disturbances are common in kidney transplant recipients, but there are few reports of low-solute hyponatremia or beer potomania in this population. We report herein a case of low-solute hyponatremia in a kidney transplant recipient with impaired graft function, highlighting key issues in diagnosis and management of low-solute hyponatremia, as well as exploring the pathophysiology of hyponatremia after kidney transplantation. CASE PRESENTATION: A 51-year-old man who had received a cadaveric renal transplant 18 years before presented with symptomatic hyponatremia and seizure. Workup for an underlying intracranial pathology was negative, and subsequent biochemical workup suggested low-solute hyponatremia with potomania, arising from dietary modifications taken by the patient while self-isolating during the COVID-19 pandemic. Correction of hyponatremia was successful with conservative management with close monitoring. CONCLUSION: This case illustrates key points in the diagnosis and management of low-solute hyponatremia and highlights the pathophysiology of hyponatremia after kidney transplantation.
Subject(s)
COVID-19 , Hyponatremia , Kidney Transplantation , Male , Humans , Middle Aged , Hyponatremia/diagnosis , Hyponatremia/etiology , Hyponatremia/therapy , Kidney Transplantation/adverse effects , Pandemics , BeerABSTRACT
OBJECTIVE: Smoking remains prevalent in many countries despite rigorous tobacco control strategies. The use of Swedish snus, a type of low-nitrosamine smokeless tobacco, has been promoted as a tobacco harm reduction strategy. DATA SOURCES AND STUDY SELECTION: Three databases were searched for studies that assessed the effectiveness of snus in promoting smoking abstinence. A total of 28 studies were reviewed (5 randomised controlled trials (RCTs), 7 longitudinal and 16 cross-sectional studies). DATA EXTRACTION: Separate meta-analyses were conducted by study type, pooling effect estimates where outcome measures and design were sufficiently comparable. Study details and quality assessment (Risk of Bias 2 for RCTs, Newcastle-Ottawa Scale for observational studies) are provided for each study. DATA SYNTHESIS: While the meta-analysis of RCTs did not show a significant association between snus use and smoking cessation (risk ratio (RR)=1.33, 95% CI 0.71 to 2.47 and RR=0.62, 95% CI 0.27 to 1.41), the results of the meta-analysis of longitudinal cohort studies (RR=1.38, 95% CI 1.05 to 1.82, p=0.022) and cross-sectional studies (OR=1.87, 95% CI 1.29 to 2.72, p=0.001) indicated that use of snus was associated with an increased likelihood of quitting or having quit smoking. There was significant heterogeneity in the cross-sectional studies, and leave-one-out analysis indicated that the longitudinal cohort results were driven by one study. Most studies examined were subject to an elevated risk of bias. CONCLUSION: There is weak evidence for the use of snus for smoking cessation. Better RCTs and longitudinal studies are needed; meanwhile, existing cessation aids may be better placed than snus to promote abstinence.
Subject(s)
Smoking Cessation , Tobacco, Smokeless , Humans , Smoking Cessation/methods , Smoking , Tobacco Use Cessation Devices , Cohort StudiesABSTRACT
INTRODUCTION: The rising popularity of TikTok among adolescents may influence their awareness and perceptions of e-cigarette use via user-generated content. This study aimed to examine how e-cigarette/vaping-related videos are portrayed on TikTok. METHODS: The nine most viewed hashtag based keywords were used to identify popular e-cigarette/vaping-related videos on TikTok (n=1000) from its inception (earliest upload date: January 2019) to November 2020. Five researchers independently coded the number of views, likes, user category and theme. RESULTS: A final sample of 808 e-cigarette/vaping-related videos that met study criteria were included. Collectively, these videos were viewed over 1.5 billion times, with a median view count of 1 000 000 (range 112 900-78 600 000) and a median 'likes' count of 143 000 (range 10 000-1 000 000). A majority of the videos portrayed e-cigarette use positively (63%; collectively viewed over 1.1 billion times). Neutral depictions of e-cigarette use were viewed a total of 290 million times (24%) and negative depictions of e-cigarettes were viewed a total of 193 million times (13%). The video themes included (not mutually exclusively): 'comedy and joke' (52%; total of 618 million views), 'lifestyle and acceptability' (35%; 459 million), 'marketing' (29%; 392 million), 'vaping tricks' (20%; 487 million), 'nicotine and addiction' (20%; 194 million), 'creativity' (16%; 322 million) and 'warning' (11%; 131 million). CONCLUSION: Our findings illustrated that positively framed e-cigarette and vaping-related postings available without age restrictions on TikTok-a rising video-sharing platform that is popular among adolescents-have been viewed many times. Effective age restrictions are needed to reduce adolescents' potential exposure to videos that portray vaping positively.
Subject(s)
Electronic Nicotine Delivery Systems , Social Media , Tobacco Products , Vaping , Adolescent , Humans , MarketingABSTRACT
Previous analysis of postentry events revealed that human cytomegalovirus (HCMV) displays a unique, extended nuclear translocation pattern in monocytes. We determined that c-Src signaling through pentamer engagement of integrins is required upon HCMV entry to avoid sorting of the virus into late endosomes and subsequent degradation. To follow up on this previous study, we designed experiments to investigate how HCMV-induced signaling through the other major axis-the epidermal growth factor receptor (EGFR) kinase-regulates viral postentry events. Here we show that HCMV induces chronic and functional EGFR signaling that is distinct to the virus as compared to the natural EGFR ligand: EGF. This chronic EGFR kinase activity in infected monocytes is required for the proper subcellular localization of the viral particle during trafficking events, as well as for promoting translocation of viral DNA into the host nucleus. Our data indicate that HCMV glycoprotein B (gB) binds to EGFR at the monocyte surface, the virus and EGFR are internalized together, and gB remains bound to EGFR throughout viral postentry events until de-envelopment to promote the chronic EGFR kinase activity required for viral trafficking and nuclear translocation. These data highlight how initial EGFR signaling via viral binding is necessary for entry, but not sufficient to promote each viral trafficking event. HCMV appears to manipulate the EGFR kinase postentry, via gB-EGFR interaction, to be active at the critical points throughout the trafficking process that leads to nuclear translocation and productive infection of peripheral blood monocytes.
Subject(s)
Cell Nucleus/metabolism , Cytomegalovirus/physiology , Monocytes/virology , Viral Envelope Proteins/metabolism , Cell Nucleus/virology , Cells, Cultured , DNA, Viral/metabolism , Endosomes/metabolism , Endosomes/virology , Epidermal Growth Factor/metabolism , ErbB Receptors/antagonists & inhibitors , ErbB Receptors/metabolism , Host-Pathogen Interactions , Humans , Monocytes/metabolism , Protein Binding , Signal Transduction , trans-Golgi Network/metabolism , trans-Golgi Network/virologyABSTRACT
Background: Vaping is an increasingly popular mode of cannabis use. Few studies have characterized the role of flavors in cannabis e-liquids.Objectives: To explore the prevalence of flavored vaping liquids, including differences between countries and correlates of use.Methods: Data were from Wave 4 (2021) of the International Cannabis Policy Study with national samples aged 16-65 in Canada, the United States (US), Australia, and New Zealand. The sample comprised 52,938 respondents, including 6,265 who vaped cannabis e-liquids in the past 12-months (2,858 females, 3,407 males). Logistic regression models examined differences in the use of flavored e-liquids between countries and sociodemographic characteristics.Results: The prevalence of vaping cannabis e-liquids was highest in the US (15.3%) and Canada (10.7%) compared to Australia (4.0%) and New Zealand (3.7%). Among past 12-month cannabis consumers, 57.5% reported using flavored vaping liquids, 34.2% used unflavored vaping products and 8.3% did not know. People who vape in Australia were most likely to report using flavored liquids compared to New Zealand (OR = 2.29), Canada (OR = 3.14), and the US (OR = 3.14) (p < .05 for all). Fruit was the most reported vaping flavor (40.8%), followed by candy/dessert (20.4%) and vanilla (15.2%). Use of flavored vapes was greater among younger, ethnic minorities, female, higher education and income adequacy, and more frequent consumers (p < .05).Conclusion: Many cannabis consumers reported using flavored e-liquids, with highest levels among young people aged 16-35. Given the high prevalence of vaping in legal markets, regulators should consider the role of flavored vaping products in promoting cannabis use among this group.
Subject(s)
Cannabis , Tobacco Products , Vaping , Male , Humans , Female , United States/epidemiology , Adolescent , Vaping/epidemiology , New Zealand/epidemiology , Canada/epidemiology , Australia/epidemiology , Public Policy , Flavoring AgentsABSTRACT
Homogeneous populations of mature differentiated primary cell types can display variable responsiveness to extracellular stimuli, although little is known about the underlying mechanisms that govern such heterogeneity at the level of gene expression. In this article, we show that morphologically homogenous human endothelial cells exhibit heterogeneous expression of VCAM1 after TNF-α stimulation. Variability in VCAM1 expression was not due to stochasticity of intracellular signal transduction but rather to preexisting established heterogeneous states of promoter DNA methylation that were generationally conserved through mitosis. Variability in DNA methylation of the VCAM1 promoter resulted in graded RelA/p65 and RNA polymerase II binding that gave rise to a distribution of VCAM1 transcription in the population after TNF-α stimulation. Microarray analysis and single-cell RNA sequencing revealed that a number of cytokine-inducible genes shared this heterogeneous response pattern. These results show that heritable epigenetic heterogeneity is fundamental in inflammatory signaling and highlight VCAM1 as a metastable epiallele.
Subject(s)
Epigenesis, Genetic/immunology , Human Umbilical Vein Endothelial Cells/immunology , Human Umbilical Vein Endothelial Cells/cytology , Humans , Promoter Regions, Genetic/immunology , RNA Polymerase II/genetics , RNA Polymerase II/immunology , Transcription Factor RelA/genetics , Transcription Factor RelA/immunology , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunology , Vascular Cell Adhesion Molecule-1/genetics , Vascular Cell Adhesion Molecule-1/immunologyABSTRACT
AIM: Type 2 diabetes (T2D) is associated with significant cardiovascular (CV) morbidity and mortality. A single-nucleotide polymorphism (SNP) in the acetyl-coenzyme A carboxylase beta (ACACB) gene, rs2268388, reproducibly associates with diabetic nephropathy (DN). ACACB regulates fatty-acid oxidation. As such, we assessed whether ACACB SNP rs2268388 was associated with CV disease in Chinese individuals with T2D. METHODS: Chinese individuals with T2D were genotyped for SNP rs2268388. Baseline demographics were recorded and clinical data regarding coronary, carotid, and peripheral arterial disease and congestive heart failure were retrieved from electronic patient records. Statistical analyses were performed to detect associations between the rs2268388 T risk allele with CV outcomes in the cohort. RESULTS: A total of 596 Chinese individuals with T2D were genotyped. Their mean age was 66.8 ± 10.9 years at the time of data extraction. Genotyping revealed 59.7%, 33.2% and 7.1% of the study population were non-carriers, heterozygous and homozygous carriers of the rs2268388 T risk allele in ACACB. No statistically significant correlations of the risk allele were observed with CV outcomes. CONCLUSION: These results did not demonstrate association between rs2268388 SNP in ACACB with CV outcomes in Chinese T2D patients. The ACACB gene and its role in CV risk susceptibility, via alterations in fatty acid oxidation, remains an interesting postulate and studies with larger cohort sizes and in different ethnic groups remain warranted.
Subject(s)
Acetyl-CoA Carboxylase , Cardiovascular Diseases , Diabetes Mellitus, Type 2 , Diabetic Nephropathies , Acetyl-CoA Carboxylase/genetics , Acetyl-CoA Carboxylase/metabolism , Aged , Cardiovascular Diseases/genetics , Cardiovascular Diseases/metabolism , Case-Control Studies , China/epidemiology , Coenzyme A/genetics , Coenzyme A/metabolism , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/genetics , Diabetes Mellitus, Type 2/metabolism , Diabetic Nephropathies/diagnosis , Diabetic Nephropathies/genetics , Diabetic Nephropathies/metabolism , Genetic Predisposition to Disease , Humans , Middle Aged , Polymorphism, Single Nucleotide , Risk FactorsABSTRACT
A human cytomegalovirus (HCMV) pentameric glycoprotein complex (PC), gH-gL-UL128-UL130-UL131A, is necessary for viral infection of clinically relevant cell types, including epithelial cells, which are important for interhost transmission and disease. We performed genome-wide CRISPR/Cas9 screens of different cell types in parallel to identify host genes specifically required for HCMV infection of epithelial cells. This effort identified a multipass membrane protein, OR14I1, as a receptor for HCMV infection. This olfactory receptor family member is required for HCMV attachment, entry, and infection of epithelial cells and is dependent on the presence of viral PC. OR14I1 is required for AKT activation and mediates endocytosis entry of HCMV. We further found that HCMV infection of epithelial cells is blocked by a synthetic OR14I1 peptide and inhibitors of adenylate cyclase and protein kinase A (PKA) signaling. Identification of OR14I1 as a PC-dependent HCMV host receptor associated with epithelial tropism and the role of the adenylate cyclase/PKA/AKT-mediated signaling pathway in HCMV infection reveal previously unappreciated targets for the development of vaccines and antiviral therapies.
Subject(s)
Cytomegalovirus/physiology , Epithelial Cells/metabolism , Multiprotein Complexes/metabolism , Signal Transduction , Viral Proteins/metabolism , Viral Tropism/physiology , A549 Cells , Cyclic AMP-Dependent Protein Kinases/genetics , Cyclic AMP-Dependent Protein Kinases/metabolism , Epithelial Cells/pathology , Epithelial Cells/virology , HEK293 Cells , HeLa Cells , Humans , Multiprotein Complexes/genetics , Proto-Oncogene Proteins c-akt/genetics , Proto-Oncogene Proteins c-akt/metabolism , Viral Proteins/geneticsABSTRACT
Human cytomegalovirus (HCMV) is a major cause of morbidity and mortality among immunocompromised and immunonaive individuals. HCMV-induced signaling initiated during viral entry stimulates a rapid noncanonical activation of Akt to drive the differentiation of short-lived monocytes into long-lived macrophages, which is essential for viral dissemination and persistence. We found that HCMV glycoproteins gB and gH directly bind and activate cellular epidermal growth factor receptor (EGFR) and integrin ß1, respectively, to reshape canonical Akt signaling within monocytes. The remodeling of the Akt signaling network was due to the recruitment of nontraditional Akt activators to either the gB- or gH-generated receptor signaling complexes. Phosphoinositide 3-kinase (PI3K) comprised of the p110ß catalytic subunit was recruited to the gB/EGFR complex despite p110δ being the primary PI3K isoform found within monocytes. Concomitantly, SH2 domain-containing inositol 5-phosphatase 1 (SHIP1) was recruited to the gH/integrin ß1 complex, which is critical to aberrant Akt activation, as SHIP1 diverts PI3K signaling toward a noncanonical pathway. Although integrin ß1 was required for SHIP1 recruitment, gB-activated EGFR mediated SHIP1 activation, underscoring the importance of the interplay between gB- and gH-mediated signaling to the unique activation of Akt during HCMV infection. Indeed, SHIP1 activation mediated the increased expression of Mcl-1 and HSP27, two Akt-dependent antiapoptotic proteins specifically upregulated during HCMV infection but not during growth factor treatment. Overall, our data indicate that HCMV glycoproteins gB and gH work in concert to initiate an HCMV-specific signalosome responsible for the atypical activation of Akt required for infected monocyte survival and ultimately viral persistence.IMPORTANCE Human cytomegalovirus (HCMV) infection is endemic throughout the world regardless of socioeconomic conditions and geographic locations with a seroprevalence reaching up to 100% in some developing countries. Although asymptomatic in healthy individuals, HCMV can cause severe multiorgan disease in immunocompromised or immunonaive patients. HCMV disease is a direct consequence of monocyte-mediated systematic spread of the virus following infection. Because monocytes are short-lived cells, HCMV must subvert the natural short life-span of these blood cells by inducing a distinct activation of Akt, a serine/theonine protein kinase. In this work, we demonstrate that HCMV glycoproteins gB and gH work in tandem to reroute classical host cellular receptor signaling to aberrantly activate Akt and drive survival of infected monocytes. Deciphering how HCMV modulates the cellular pathway to induce monocyte survival is important to develop a new class of anti-HCMV drugs that could target and prevent spread of the virus by eliminating infected monocytes.
Subject(s)
Proto-Oncogene Proteins c-akt/metabolism , Viral Envelope Proteins/metabolism , Cell Line , Cells, Cultured , Cytomegalovirus/pathogenicity , Cytomegalovirus/physiology , Cytomegalovirus Infections/metabolism , ErbB Receptors/metabolism , Host-Pathogen Interactions , Humans , Macrophages/metabolism , Monocytes/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Signal Transduction , Transcriptional Activation , Viral Envelope Proteins/physiology , Viral Fusion Proteins/metabolism , Virus InternalizationABSTRACT
Key to the viral dissemination strategy of human cytomegalovirus (HCMV) is the induction of monocyte survival, where monocytes are normally short-lived cells. Autophagy is a cellular process that preserves cellular homeostasis and promotes cellular survival during times of stress. We found that HCMV rapidly induced autophagy within infected monocytes. The early induction of autophagy during HCMV infection was distinctly required for the survival of HCMV-infected monocytes, as repression of autophagosome formation led to cellular death of infected cells but had no effect on the viability of uninfected monocytes. The inhibition of caspases was insufficient to rescue cell viability of autophagy-repressed infected monocytes, suggesting that autophagy was not protecting cells from apoptosis. Accordingly, we found that HCMV blocked the activation of caspase 8, which was maintained in the presence of autophagy inhibitors. Necroptosis is an alternative form of cell death triggered when apoptosis is impeded and is dependent on RIPK3 phosphorylation of MLKL. Although we found that HCMV activated RIP3K upon infection, MLKL was not activated. However, inhibition of autophagy removed the block in RIPK3 phosphorylation of MLKL, suggesting that autophagy was protecting infected monocytes from undergoing necroptosis. Indeed, survival of autophagy-inhibited HCMV-infected monocytes was rescued when MLKL and RIPK3 were suppressed. Taken together, these data indicate that HCMV induces autophagy to prevent necroptotic cell death in order to ensure the survival of infected monocytes and thus facilitate viral dissemination within the host.IMPORTANCE Human cytomegalovirus (HCMV) infection is endemic throughout the world, with a seroprevalence of 40 to 100% depending on geographic location. HCMV infection is generally asymptomatic, but can cause severe inflammatory organ diseases in immunocompromised individuals. The broad array of organ diseases caused by HCMV is directly linked to the systematic spread of the virus mediated by monocytes. Monocytes are naturally programmed to undergo apoptosis, which is rapidly blocked by HCMV to ensure the survival and dissemination of infected monocytes to different organ sites. In this work, we demonstrate infected monocytes also initiate necroptosis as a "trap door" death pathway in response to HCMV subversion of apoptosis. HCMV then activates cellular autophagy as a countermeasure to prevent the execution of necroptosis, thereby promoting the continued survival of infected monocytes. Elucidating the mechanisms by which HCMV stimulates monocyte survival is an important step to the development of novel anti-HCMV drugs that prevent the spread of infected monocytes.
Subject(s)
Autophagy/physiology , Cytomegalovirus Infections/virology , Cytomegalovirus/physiology , Monocytes/metabolism , Apoptosis , Caspase 8/metabolism , Cell Survival , Cytomegalovirus/pathogenicity , Host-Pathogen Interactions , Humans , Monocytes/virology , Necroptosis , Phosphorylation , Receptor-Interacting Protein Serine-Threonine Kinases , Seroepidemiologic StudiesABSTRACT
The herpesviruses varicella-zoster virus (VZV) and human cytomegalovirus (HCMV) are endemic to humans. VZV causes varicella (chicken pox) and herpes zoster (shingles), while HCMV causes serious disease in immunocompromised patients and neonates. More effective, less toxic antivirals are needed, necessitating better models to study these viruses and evaluate antivirals. Previously, VZV and HCMV models used fetal tissue; here, we developed an adult human skin model to study VZV and HCMV in culture and in vivo While VZV is known to grow in skin, it was unknown whether skin could support an HCMV infection. We used TB40/E HCMV and POka VZV strains to evaluate virus tropism in skin organ culture (SOC) and skin xenograft mouse models. Adult human skin from reduction mammoplasties was prepared for culture on NetWells or mouse implantation. In SOC, VZV infected the epidermis and HCMV infected the dermis. Specifically, HCMV infected fibroblasts, endothelial cells, and hematopoietic cells, with some infected cells able to transfer infection. VZV and HCMV mouse models were developed by subcutaneous transplantation of skin into SCID/beige or athymic nude mice at 2 independent sites. Viruses were inoculated directly into one xenograft, and widespread infection was observed for VZV and HCMV. Notably, we detected VZV- and HCMV-infected cells in the contralateral, uninoculated xenografts, suggesting dissemination from infected xenografts occurred. For the first time, we showed HCMV successfully grows in adult human skin, as does VZV. Thus, this novel system may provide a much-needed preclinical small-animal model for HCMV and VZV and, potentially, other human-restricted viruses.IMPORTANCE Varicella-zoster virus and human cytomegalovirus infect a majority of the global population. While they often cause mild disease, serious illness and complications can arise. Unfortunately, there are few effective drugs to treat these viruses, and many are toxic. To complicate this, these viruses are restricted to replication in human cells and tissues, making them difficult to study in traditional animal models. Current models rely heavily on fetal tissues, can be prohibitively expensive, and are often complicated to generate. While fetal tissue models provide helpful insights, it is necessary to study human viruses in human tissue systems to fully understand these viruses and adequately evaluate novel antivirals. Adult human skin is an appropriate model for these viruses because many target cells are present, including basal keratinocytes, fibroblasts, dendritic cells, and lymphocytes. Skin models, in culture and xenografts in immunodeficient mice, have potential for research on viral pathogenesis, tissue tropism, dissemination, and therapy.
Subject(s)
Chickenpox/virology , Cytomegalovirus/physiology , Herpes Zoster/virology , Herpesvirus 3, Human/physiology , Skin/virology , Animals , Antiviral Agents/pharmacology , Chickenpox/pathology , Cytomegalovirus/drug effects , Disease Models, Animal , Endothelial Cells , Fibroblasts/pathology , Fibroblasts/virology , Herpes Zoster/pathology , Herpesvirus 3, Human/drug effects , Heterografts , Humans , Male , Mice , Mice, Nude , Mice, SCID , Organ Culture Techniques , Skin/pathologyABSTRACT
BACKGROUND: Human cytomegalovirus (HCMV) resides latently in cells of the myeloid compartment, including CD34+ hematopoietic progenitor cells and circulating monocytes. Healthy hosts maintain the virus latently, and this infection is, for the most part, asymptomatic. However, given the proper external cues, HCMV reactivates from latency, at which point the virus disseminates, causing disease. The viral and cellular factors dictating the balance between these phases of infection are incompletely understood, though a large body of literature support a role for viral-mediated manipulation of host cell signaling. MAIN BODY: To establish and maintain latency, HCMV has evolved various means by which it usurps host cell factors to alter the cellular environment to its own advantage, including altering host cell signaling cascades. As early as virus entry into myeloid cells, HCMV usurps cellular signaling to change the cellular milieu, and this regulation includes upregulation, as well as downregulation, of different signaling cascades. Indeed, given proper reactivation cues, this signaling is again altered to allow for transactivation of viral lytic genes. CONCLUSIONS: HCMV modulation of host cell signaling is not binary, and many of the cellular pathways altered are finely regulated, wherein the slightest modification imparts profound changes to the cellular milieu. It is also evident that viral-mediated cell signaling differs not only between these phases of infection, but also is myeloid cell type specific. Nonetheless, understanding the exact pathways and the means by which HCMV mediates them will undoubtedly provide novel targets for therapeutic intervention.
Subject(s)
Cytomegalovirus , Virus Latency , Cells, Cultured , Cytomegalovirus/genetics , Host-Pathogen Interactions , Signal Transduction , Virus Latency/geneticsABSTRACT
BACKGROUND: The potential long-term safety and efficacy of aliskiren in nondiabetic chronic kidney disease (CKD) are unknown. We sought to investigate the renoprotective effect of aliskiren on nondiabetic CKD patients. METHODS: In this open-label, parallel, randomized controlled trial, nondiabetic CKD Stages 3-4 patients were randomized to receive aliskiren added to an angiotensin II receptor blocker (ARB) at the maximal tolerated dose, or ARB alone. Primary outcome was the rate of change in estimated glomerular filtration rate (eGFR). Secondary endpoints included rate of change in urine protein-to-creatinine ratio (UPCR), cardiovascular events and hyperkalemia. Composite renal outcomes of doubling of baseline serum creatinine or a 40% reduction in eGFR or incident end-stage renal disease or death were analyzed as post hoc analysis. RESULTS: Seventy-six patients were randomized: 37 to aliskiren (mean age 55.1 ± 11.1 years) and 39 to control (mean age 55.0 ± 9.4 years). Their baseline demographics were comparable to eGFR (31.9 ± 9.0 versus 27.7 ± 9.0 mL/min/1.73 m2, P = 0.05) and UPCR (30.7 ± 12.6 versus 47.8 ± 2.8 mg/mmol, P = 0.33) for treatment versus control subjects. After 144 weeks of follow-up, there was no difference in the rate of eGFR change between groups. Six patients in the aliskiren group and seven in the control group reached the renal composite endpoint (16.2% versus 17.9%, P = 0.84). The cardiovascular event rate was 10.8% versus 2.6% (P = 0.217). The hyperkalemia rate was 18.9% versus 5.1% with an adjusted hazard ratio of 7.71 (95% confidence interval 1.14 to 52.3, P = 0.04) for the aliskiren arm. CONCLUSION: Aliskiren neither conferred additional renoprotective benefit nor increased adverse events, except for more hyperkalemia in nondiabetic CKD patients.
Subject(s)
Renal Insufficiency, Chronic , Renin , Adult , Aged , Angiotensin Receptor Antagonists , Angiotensin-Converting Enzyme Inhibitors , Glomerular Filtration Rate , Humans , Middle Aged , Prospective Studies , Renal Insufficiency, Chronic/complications , Renal Insufficiency, Chronic/drug therapyABSTRACT
BACKGROUND: Different forms of alcohol-related harm (e.g., hangovers, fighting) may confer differential risk of clinically relevant alcohol problems. We examine: (i) patterns of transition in experiencing alcohol-related harms across adolescence; (ii) whether factors in early adolescence predict transition patterns; and (iii) whether transition patterns predict later alcohol use disorder (AUD) symptoms. METHODS: We used a longitudinal Australian cohort (n = 1828) to model latent class transition patterns of alcohol-related harms across three timepoints (Mage = 13.9, 16.8, 18.8 years). Regression models assessed whether child, peer, and parent factors in early adolescence (Mage = 12.9) predicted harms transition patterns and whether these patterns predicted AUD symptoms in early adulthood (Mage = 19.8). RESULTS: Five transition patterns characterized most of the cohort (n ≈ 1609, 88.0%): (i) minimal harms (n ≈ 381, 20.8%); (ii) late physiological harms (n ≈ 702, 38.4%); (iii) early physiological harms (n ≈ 226, 12.4%); (iv) late all harms (n ≈ 131, 7.2%); and (v) gradual all harms (n ≈ 169, 9.2%). With late physiological harms as the reference, females had increased risk of experiencing early physiological harms (relative risk [RR]: 2.15; 99.5% CI: 1.19, 3.90). Late all harms (RR: 1.71; CI: 1.19, 2.47) and gradual all harms (RR: 1.84; CI: 1.37, 2.47) were each associated with increased odds of meeting criteria for AUD, even when patterns of alcohol consumption are considered. CONCLUSIONS: Adolescents display heterogeneous transition patterns across physiological and psychosocial alcohol-related harms. Females are at greater risk of experiencing early physiological harms. Experience of both physiological and psychosocial harms in late adolescence is an important and potentially modifiable precursor to clinically relevant alcohol problems in early adulthood.
Subject(s)
Alcohol Drinking/adverse effects , Alcohol-Related Disorders/diagnosis , Severity of Illness Index , Underage Drinking/statistics & numerical data , Adolescent , Adult , Australia , Female , Humans , Longitudinal Studies , Male , Peer Group , Prospective Studies , Risk Factors , Sex Factors , Young AdultABSTRACT
AIM: Darbepoetin alpha is available as Aranesp® and NESP®, which differ in the inactive component and maximum dose-strength of prefilled syringes. We conducted an observational cohort study to investigate optimal conversion strategies and the feasibility of extending dosing intervals with higher-dose preparations in dialysis patients converting from Aranesp® to NESP®. METHODS: Adult dialysis patients on Aranesp® with stable haemoglobin of 9-12 g/dL were converted to NESP® at the same monthly total dose according to one of three conversion regimens. Group A included patients on ≤80 mcg/month of Aranesp® who converted with dosing regimen unchanged. Group B patients converted to NESP® with extended dosing intervals using higher individual dose preparations. Group C were patients on 100 mcg Aranesp® who converted to NESP® 120 mcg with extended dosing intervals. Patients were observed for 6 months. RESULTS: Fifty patients were included. All 24 Group A patients maintained stable haemoglobin. In Group B, 10 patients (50%) maintained stable haemoglobin with extension of dosing interval from 1.04 ± 0.14 to 3.03 ± 1.28 weeks. Factors associated with success in extending dosing interval included a lower prevalence of cardiovascular disease and a higher Kt/Vurea in peritoneal dialysis patients. Four patients (80%) in Group C maintained stable haemoglobin after conversion to NESP® 120 mcg with extended dosing interval. The use of NESP® 120 mcg was well tolerated, and was associated with reduced patient-reported pain score and 38% reduction of drug cost. CONCLUSION: Dialysis patients on Aranesp® can be successfully converted to NESP® and the dosing interval can be extended successfully in a significant proportion of patients, which could reduce discomfort and drug cost.