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Selection Pressure in the Human Adenovirus Fiber Knob Drives Cell Specificity in Epidemic Keratoconjunctivitis.

UNLABELLED: Human adenoviruses (HAdVs) contain seven species (HAdV-A to -G), each associated with specific disease conditions. Among these, HAdV-D includes those viruses associated with epidemic keratoconjunctivitis (EKC), a severe ocular surface infection. The reasons for corneal tropism for some but not all HAdV-Ds are not known. The fiber protein is a major capsid protein; its C-terminal "knob" mediates binding with host cell receptors to facilitate subsequent viral entry. In a comprehensive phylogenetic analysis of HAdV-D capsid genes, fiber knob gene sequences of HAdV-D types associated w…

Analysis of Cell Populations from Arbovirus-Infected Tissues by Flow Cytometry.

Arboviruses still represent a major challenge to public health in many parts of the world. Despite shared epidemiological characteristics, each arboviral disorder displays distinct cellular tropism and activation patterns, progressing to immunopathological outcomes that remain not fully elucidated. A deeper understanding of these processes requires methodologies capable of characterizing the often-complex cellular responses. In this context, flow cytometry emerges as a valuable tool, enabling the characterization of heterogeneous cell populations, the assessment of activation and proliferation…

Erythroid cells and malaria parasites: it's a match!

PURPOSE OF REVIEW: The current review outlines recent discoveries on the infection of erythroid cells by Plasmodium parasites, focusing on the molecular interactions governing the tropism of parasites for their host cell and the implications of this tropism for parasite biology and erythroid cell maturation. RECENT FINDINGS: Although most studies about the interactions of Plasmodium parasites and their host cell focused on the deadliest human malaria parasite, Plasmodium falciparum, and the erythrocyte, there is increasing evidence that several Plasmodium species, including P. falciparum, als…

Rapid Lymphatic Dissemination of Encapsulated Group A Streptococci via Lymphatic Vessel Endothelial Receptor-1 Interaction.

The host lymphatic network represents an important conduit for pathogen dissemination. Indeed, the lethal human pathogen group A streptococcus has a predilection to induce pathology in the lymphatic system and draining lymph nodes, however the underlying basis and subsequent consequences for disease outcome are currently unknown. Here we report that the hyaluronan capsule of group A streptococci is a crucial virulence determinant for lymphatic tropism in vivo, and further, we identify the lymphatic vessel endothelial receptor-1 as the critical host receptor for capsular hyaluronan in the lymph…

Гуманизированные модели острого комбинированного иммунодостаточного мышьяка для вирусного патогенеза Варицеллы-Зостер.

Вирус Вариселлы-Зостер (VZV) является вирусом, ограничивающим здоровье человека, что создает препятствия для исследований. Строгий тропизм человека ограничивает знания о его патогенезе и создает проблемы для оценки противовирусных препаратов и вакцин. Разработка гуманизированных моделей мыши была обусловлена необходимостью решения этих проблем. Здесь мы резюмируем гуманизированные модели мыши с ксенографами тимуса/ливерных органоидов, кожи, дорсальной корневой ганглии и легких тканей. Эти модели показали, что ОРФ ВЗВ связаны с клеточным тропизмом и патогенезом в различных тканях, и позволили о

Совпадение в аннотации оригинала
Varicella-zoster virus (VZV) is a human-restricted virus, which raises obstacles to research. The strict human tropism limits knowledge about its pathogenesis and creates challenges for evaluating antiviral treatments and vaccines. The development of humanized mouse models was driven by the need to address these challenges. Here, we summarize the humanized m…

Duck circovirus induces a new pathogenetic characteristic, primary sclerosing cholangitis.

Primary sclerosing cholangitis (PSC) is a chronic, cholestatic liver disease of unknown cause. In the study, we found that duck circovirus (DuCV) induces PSC in natural and reproductive cases. PSC in DuCV naturally infected ducks was investigated by PCR and histopathology. A model of PSC was developed in one-day old duck by infection of DuCV. Effects on serum levels of liver enzymes and histology were evaluated, and DuCV tropism for bile duct in liver was analyzed by immuohistochemistry. Pathology observation of natural or reproductive DuCV infected ducks showed that the lesion of liver were c…

Co-receptor usage in distinct phylogenetic clusters of HIV-1 CRF01_AE is associated with differential immune reconstitution after antiretroviral therapy.

HIV-1 CRF01_AE cluster 4 is the predominant strain among men who have sex with men (MSM) in China and comprises two lineages, clusters 4a an … Cox regression models to evaluate determinants of the CD4+ T-cell normalization. HIV-1 co-receptor tropism was inferred using Geno2pheno. We included 604 patients (391 cluster 4a, 213 cluster 4b). Patients with cluster 4a exhibited a significantly slower recovery rate than those with cluster 4b (β: -9.88 cells/μL/year; interaction term P = 0.006). Relati …

Type I IFN signaling limits hemorrhage-like disease after infection with Japanese encephalitis virus through modulating a prerequisite infection of CD11b+Ly-6C+ monocytes.

BACKGROUND: The crucial role of type I interferon (IFN-I, IFN-α/β) is well known to control central nervous system (CNS) neuroinflammation caused by neurotrophic flaviviruses such as Japanese encephalitis virus (JEV) and West Nile virus. However, an in-depth analysis of IFN-I signal-dependent cellular factors that govern CNS-restricted tropism in JEV infection in vivo remains to be elucidated. METHODS: Viral dissemination, tissue tropism, and cytokine production were examined in IFN-I signal-competent and -incompetent mice after JEV inoculation in tissues distal from the CNS such as the footp…

Rethinking COVID-19 seasonality: A summer respiratory virus in the tropics, contrast to influenza.

This opinion challenges the conventional view that coronavirus disease 2019 behaves as a uniformly winter-dominant respiratory infection. Analysis of multi-year surveillance data across hemispheres reveals that severe acute respiratory syndrome coronavirus-2 exhibits seasonal divergence, with consistent summer surges in tropical regions, such as India, and winter peaks in temperate climates. We propose that this pattern arises primarily from human (host) behavioural responses to multi-animal tropism to climatic (environment) extremes, which recreate high-risk indoor transmission settings under…

Arboviruses and Muscle Disorders: From Disease to Cell Biology.

Infections due to arboviruses (arthropod-borne viruses) have dramatically increased worldwide during the last few years. In humans, symptoms … ntified. Animal models provide insights to elucidate pathological mechanisms through studying viral tropism, viral-induced inflammation, or potential viral persistence in the muscle compartment. The tropism of arboviruses for muscle cells as well as the viral-induced cytopathic effect and cellular alterations can be confirmed in vitro using cellular model …

O'nyong-nyong virus adaptive mutations in non-structural protein 1 and 3 enhance RNA replication and overcome FHL1 requirement.

Arthritogenic alphaviruses, like o'nyong-nyong virus (ONNV), cause debilitating musculoskeletal diseases and are geographically expanding. To predict their emergence, we seek to better understand evolutionary mechanisms that enable changes in virus tropism. Here, we identify adaptive mutations in the ONNV non-structural proteins (nsPs) that arose during cellular serial passaging and enabled ONNV to infect non-permissive Lunet cells. Using shotgun proteomics, we show that this human hepatoma cell line lacks the four-and-a-half-LIM domain protein 1 (FHL1), an essential host factor in ONNV RNA re…

Selective transduction of astrocytic and neuronal CNS subpopulations by lentiviral vectors pseudotyped with Chikungunya virus envelope.

Lentiviral vectors are gene delivery vehicles that integrate into the host genome of dividing and non-dividing mammalian cells facilitating long-term transgene expression. Lentiviral vector versatility is greatly increased by incorporating heterologous viral envelope proteins onto the vector particles instead of the native envelope, conferring on these pseudotyped vectors a modified tropism and host range specificity. We investigated the pseudotyping efficiency of HIV-1 based lentiviral vectors with alphaviral envelope proteins from the Chikungunya Virus (CHIKV-G) and Sindbis Virus (SINV-G). F…

Early and late promoters of BK polyomavirus, Merkel cell polyomavirus, Trichodysplasia spinulosa-associated polyomavirus and human polyomavirus 12 are among the strongest of all known human polyomaviruses in 10 different cell lines.

Recently, 11 new human polyomaviruses (HPyVs) have been isolated and named KI, WU, Merkel cell polyomavirus (MCPyV), HPyV6,  -7,  -9,  -10 and  -12, Trichodysplasia spinulosa-associated polyomavirus (TSPyV), STLPyV and NJPyV-2013. Little is known about cell tropism of the novel HPyVs, and cell cultures allowing virus propagation are lacking. Because viral tropism partially depends on the interaction of cellular transcription factors with the viral promoter, we monitored the promoter activity of all known HPyVs. Therefore, we compared the relative early and late promoter activity of the BK poly…

Maraviroc, risks and benefits: a review of the clinical literature.

BACKGROUND: Maraviroc represents the first licensed CCR5 co-receptor antagonist from the new antiretroviral (ARV) drug-class of entry inhibi … mbination partner in ARV therapy. As maraviroc however is only effective against CCR5-tropic HIV-1, tropism testing is required before initiation of treatment. Tropism-testing possibilities are still limited, and presently only possible at high costs. The main constraints to be considered in the clinical use of maraviroc are the declining number of CCR5-t …

In vitro susceptibility to fostemsavir is not affected by long-term exposure to antiviral therapy in MDR HIV-1-infected patients.

OBJECTIVES: Fostemsavir is the prodrug of the HIV-1 attachment inhibitor temsavir and is currently under clinical assessment in heavily treatment-experienced patients with limited therapeutic options. We evaluated the genotypic and phenotypic susceptibility to temsavir in a panel of samples collected from patients harbouring MDR strains enrolled in the Italian PRESTIGIO Registry. METHODS: Plasma samples from 24 patients were used for HIV-1 gp120 sequencing, while viral tropism and susceptibility to temsavir were assessed through a homemade phenotypic assay with pseudotyped viruses expressing …

Correlation between the Trofile test and virological response to a short-term maraviroc exposure in HIV-infected patients.

OBJECTIVES: The current validated assay to determine tropism of HIV variants is Trofile, which has some limitations. The aim of this work was to correlate the virological response to a short-term maraviroc exposure with Trofile. METHODS: From 1 July 2008 to 1 March 2009, 34 consecutive HIV-infected patients with detectable viral load during the last 6 months began an 8 day exposure to maraviroc (MCT group); six HIV-infected patients without antiretroviral therapy received no treatment (control group). Plasma viral load was evaluated on days 0, 2, 5 and 8. Baseline Trofile was performed in MCT…

Exploring Routes of Infection of Severe Fever with Thrombocytopenia Syndrome Virus Using Experimentally Infected Animals.

Reports from endemic regions in Asia indicate that severe fever with thrombocytopenia syndrome virus (SFTSV), a canonically tick-borne virus, can be directly transmitted from infected humans and animals to naïve hosts. To understand this process, using a feline infection model, we observed that both intramuscular inoculation and oral inoculation resulted in adult cats developing viremia, with cats inoculated intramuscularly shedding virus orally. We also observed a potential organ tropism associated with the route of inoculation. Using an immunodeficient murine model, we further demonstrated t…

Role of H7 hemagglutinin in murine infectivity of influenza viruses following ocular inoculation.

H7 subtype influenza viruses have demonstrated an ocular tropism in humans, causing conjunctivitis and not respiratory symptoms in many infected individuals. However, the molecular determinants which confer ocular tropism are still poorly understood. Here, we used a murine model of ocular inoculation to demonstrate that H7 influenza viruses are more likely to cause infection following ocular exposure than are non-H7 subtype viruses. We included investigation regarding the potential role of several properties of influenza viruses with murine infectivity following ocular inoculation, including v…

Combining RNAScope and RCA reveals a novel epitheliotropic bovine xipapillomavirus in udder papillomas.

The diversity of papillomaviruses (PVs) remains largely unexplored, with many viral types still unidentified among mammalian hosts. Data on … cing confirmed the viral presence, enabling genetic characterization and assessment of its cellular tropism. Based on our findings, we propose classifying this novel PV as a new type within the Bovine papillomavirus species, designated BPV45. Results revealed that BPV45 is an epitheliotropic virus closely related to BPV12 and belongs to the species Xipapi …

Selective Accumulation of Poly(Lactic-Co-Glycolic Acid) Nanoparticles in Endotheliocytes and Mesenchymal Stromal Cells Cultured as Mixed-Cell Spheroids.

The use of drug-loaded nanoparticles is an actively developed approach in targeted cancer therapy. Prevascularized spheroids generated from mesenchymal stem cells and endotheliocytes are considered as a model to evaluate the tropism of therapeutic nanoparticles to a specific tissue. Nanoparticles based on co-polymer of lactic and glycolic acids (poly(lactic-co-glycolic acid; PLGA) labeled with cyanine dye (Cy5) were incubated with prevascularized spheroids, and the rate of their penetration and their distribution in the spheroid-forming cells were evaluated. Endotheliocytes more intensively ac…