Herpesviridae Family Research Articles

The frequency of detected pathogen genomes in children with acute respiratory infections

Due to the high prevalence of acute respiratory infections in children, it was of interest to determine the composition of bacterial and viral-bacterial associations for respiratory tract inhabiting microorganisms. To identify respiratory tract pathogens, especially viruses and unculturable bacteria, it is advisable to use molecular genetic research methods particularly PCR. The work was aimed at comparatively analyzing rate of genome detection for respiratory tract pathogens in children with acute respiratory infections and apparently healthy controls. Materials and methods. Children (97 people) were examined, of which 35 people — with acute respiratory infections of the upper respiratory tract (nasopharyngitis, pharyngitis, laryngitis) (ARI URT), 32 people — with acute respiratory infections of the lower respiratory tract (acute bronchitis, acute obstructive bronchitis) (ARI NDP) and 30 people — apparently healthy control at the time of examination. RNA and DNA of viral and bacterial pathogens were assessed in the oropharyngeal smears using PCR. Test systems produced by the Federal Budgetary Institution Central Research Institute of Epidemiology of Rospotrebnadzor and JSC Vector-Best were used. Results. An analysis of detection rate for DNA and RNA of bacterial and viral pathogens showed the presence of a wide range of them (20 different species/strains out of 27 identified) in oropharyngeal biomaterial from all examined children. The peak diversity and detection rate of pathogen genomes were found in apparently healthy subjects and children with ARI UDP (DNA of members from Herpesviridae family, S. pneumoniae, H. influaenzae, MSSA, MRCoNS). Associations of 4–6 pathogens prevailed in the microflora, and the “core” of both bacterial and viral-bacterial associations was the combination of S. pneumoniae and H. influenzae (in 93.3% and 60.0% of cases, respectively). In bacterial associations, staphylococci (MRSA and MRCoNS) and P. aeruginosa were also detected in healthy children, MSSA and other very rarely bacterial types were detected in children with ARI UDP. In children with NPD infections, the majority of whom (75.0±7.7%) were classified as long-term ill and had a complicated disease course, a noticeable depletion (decrease in taxonomic diversity) of the nasopharyngeal microbiota was found. Conclusion. The presented data indicate the presence in the biomaterial of the examined children of molecular genetic markers of a wide range of pathogens presented as viral-bacterial and bacterial associations, with varying composition being related to patient clinical status. Detection of pathogen genomes is important for choosing proper etiotropic therapy at early disease stages as well as prescribing probiotic drugs that can restore a balance in respiratory tract microflora.

Development of a reporter feline herpesvirus-1 for antiviral screening assays

Feline herpesvirus type 1 (FHV-1), a member of the Herpesviridae family, is one of the most important pathogens that causes upper respiratory tract disease in felines. Following infection, FHV-1 can spread retrogradely to the trigeminal ganglia, establishing a life-long latency. Although vaccines are available for routine feline vaccination, FHV-1 is still an agent that poses a serious threat to feline health. There are currently no specific drugs for the treatment of FHV-1. To facilitate the screening of antiviral drugs, we constructed a reporter FHV-1 virus, which expresses a secreted Gaussia luciferase (GLuc) and a bright green fluorescent protein, mNeonGreen. The reporter virus shows slower growth than does the wild-type FHV-1. The expression of the two reporter genes, Gluc and mNeonGreen, was consistent with viral propagation and remained stable during continuous passage in CRFK cells, even after twenty rounds. In addition, the known inhibitor ganciclovir was used to confirm the characteristics of the reporter virus for drug screening. We found that the reporter FHV-1 is suitable for antiviral screening assays. Overall, our work provides a useful tool for screening drugs to combat FHV-1.

Determination of antimicrobial resistance genes in patients with infected miscarriage. A rapid identification and optimized empirical therapy

BACKGROUND: The infectious factor during pregnancy remains the leading cause not only of maternal mortality, but also of premature pregnancy loss and subsequent reproductive function impairment. Patients with infected miscarriage represent a special cohort in terms of complexity of clinical decision-making, while the choice of antimicrobial chemotherapy is particularly difficult in conditions of accumulation of scientific knowledge about the main microbial agents. For adequate treatment, it is essential to use all modern methods of microbiota diagnosis and conduct regular monitoring of microorganism resistance in order to update empirical schemes of antibacterial therapy. AIM: The aim of this study was to evaluate the correlation relationship between antimicrobial resistance genes and identified microbial agents in patients with infected miscarriage in order to optimize empirical antimicrobial chemotherapy. MATERIALS AND METHODS: We prospectively studied 42 samples of genital tract discharge in patients with infected miscarriage. The classical culture method was used to determine microorganism sensitivity to standard antibacterial drugs by the disc diffusion test. A molecular genetic study of the species composition of clinically significant microbial agents and genes of resistance to β-lactam and glycopeptide antibiotics was performed using Femoflor Screen and BakRezista GLA test systems (“DNA-Technology” LLC., Russia), respectively. RESULTS: In the cultural study, one microbial agent was identified in 59.5% of cases, two in 40.0% of cases, and three in 7.1% of cases. The following microorganisms were most frequently identified: Enterococcus spp. in 25.0% of cases, Esherichia coli in 16.7% of cases, and Candida spp. in 11.7% of cases. During the molecular genetic study, Lactobacillus spp. were identified in 64.3% of the samples, the microorganisms associated with bacterial vaginosis in 45.3% of the samples, Candida spp. in 23.8% of the samples, and Herpesviridae family viruses in 14.3% of the samples. In 45.2% of the samples, one to 14 genes of resistance to β-lactam and glycopeptide antibiotics were identified, while Tem (19.0%), Oxa-40-like (19.0%), Stx-M1 (14.3%), Ges (14.3%), Oxa-51-like (11.9%), and Van A/B (9.5%) were most frequently determined in the samples positive for resistance genes. Comparison between phenotypic susceptibility testing and genetic prediction for antibiotics resistance demonstrated that the specificity varied from 96.4 to 100%, and the sensitivity from 40.0 to 85.7%. CONCLUSIONS: The use of molecular genetic diagnostic methods allows for the identification of clinically significant urogenital tract infections and the detection of markers of their resistance to β-lactam antibiotics and glycopeptides in the shortest possible time. The data obtained make it possible to optimize the initial antimicrobial chemotherapy.

The antiviral activity of myricetin against pseudorabies virus through regulation of the type I interferon signaling pathway.

PRV, belonging to the Herpesviridae family, is an easily overlooked zoonotic pathogen that can threaten human health. The immunoprotective efficacy of conventional vaccines is significantly reduced due to the continuous mutation of the PRV genome, which constantly generates new viral strains. Therefore, there is a need to develop potent therapeutic drugs. PRV is capable of evading the host's natural immunity by suppressing the host's type I interferon signaling pathway, and the search for drugs that activate natural immunity can induce the body to produce type I IFN interferon and exert antiviral effects. Accordingly, the present study sought to identify active compounds from flavonoids that modulate the type I IFN interferon signaling pathway and thus inhibit the proliferation of PRV, which provides a new idea for the development of anti-PRV drugs from flavonoids that modulate the type I IFN interferon signaling pathway to enhance the body's antiviral immunity.

Molecular mimicry as a mechanism of viral immune evasion and autoimmunity

Mimicry of host protein structures, or ‘molecular mimicry’, is a common mechanism employed by viruses to evade the host’s immune system. Short linear amino acid (AA) molecular mimics can elicit cross-reactive antibodies and T cells from the host, but the prevalence of such mimics throughout the human virome has not been fully explored. Here we evaluate 134 human-infecting viruses and find significant usage of linear mimicry across the virome, particularly those in the Herpesviridae and Poxviridae families. Furthermore, host proteins related to cellular replication and inflammation, autosomes, the X chromosome, and thymic cells are enriched as viral mimicry targets. Finally, we find that short linear mimicry from Epstein-Barr virus (EBV) is higher in auto-antibodies found in patients with multiple sclerosis than previously appreciated. Our results thus hint that human-infecting viruses leverage mimicry in the course of their infection, and that such mimicry may contribute to autoimmunity, thereby prompting potential targets for therapies.

CURRENT PERSPECTIVES OF VIROTHERAPY AS A CANCER TREATMENT STRATEGY

Abstract Analysis of scientific literature presented in the main databases (PubMed, CyberLeninka, Google Scholar, Scopus) evidence that after cardiovascular diseases malignant tumors hold the second place among the most common causes of mortality in both developed and developing countries, with therapy of oncological diseases requiring to seek out for new approaches, since many types of malignant tumors are resistant to traditional treatment methods. The review was aimed at assessing a potential of virotherapy application for treatment of oncologic diseases in modern conditions. The review evaluates one of treatment methods for oncologic diseases based on using oncolytic viruses, including 9 families (Herpesviridae, Adenoviridae, Picornaviridae, Parvoviridae, Reoviridae, Poxviridae, Paramyxoviridae, Togaviridae, Rhabdoviridae) – a virotherapy, and briefly outlines its development, including Russia. The described mechanisms of action for oncolytic viruses are divided into two groups: i) recognition by oncolytic viruses of specific receptors on tumor cells, their infection and destruction via autophagy, necrosis, apoptosis, pyroptosis or blast pathway; ii) activation of antitumor immunity. Molecular basement of oncolytic virus action is discussed including types of virotherapy application, opportunity to combine oncolytic virus therapy with other means of oncologic diseases treatment. Some drugs based on such approaches are described, particularly talimogene laherparepvec (TVEC) that was approved in 2015 by the U.S. Food and Drug Administration (FDA). Clinical trials with oncolytic virus-based drugs and their results are presented. It is concluded that virotherapy is a promising direction in treatment of oncologic diseases, which has a number of advantages over traditional methods of treatment, but at the same time has a number of disadvantages and requires further investigation.

Unveiling the Impact of Human Herpesviruses-Associated on CNS Infections: An Observational Study.

This retrospective cohort study included 895 patients suspected of viral CNS infections, utilizing molecular diagnosis via qPCR to identify HHVs in cerebrospinal fluid (CSF) samples. This was conducted at a reference tertiary care hospital for infectious diseases in the western Brazilian Amazon from January 2015 to December 2022, focusing on the Herpesviridae family's clinical repercussions and of Cytomegalovirus in CNS infections. The findings revealed that 7.5% of the analyzed samples tested positive for HHVs, with Human Cytomegalovirus (HCMV) and Epstein-Barr Virus (EBV) being the most prevalent. A significant association was found between HHVs and neurological diseases such as encephalitis and meningitis, especially among people living with HIV/AIDS (PLWHA), highlighting the opportunistic nature of these viruses. The study underscores the critical role of CSF analysis in diagnosing CNS infections and the complexity of managing these infections in HIV patients due to their immunocompromised status. The results emphasize the need for comprehensive diagnostic approaches and tailored treatment strategies for CNS infections in immunocompromised individuals. The study calls for ongoing research and advancements in clinical practice to improve patient outcomes facing CNS infections, particularly those caused by HHVs.

Bacteriophages Phi 8 and Phi 12 host infection are inhibited by OMVs and LPS purified from P. pseudoalcaligenes strain: East River Isolate A.

Most phage families studied to date use a tailed appendage, composed of a multitude of proteins, for cellular recognition, membrane penetration, and genome injection. This contrasts with members of the Cystoviridae family which possess a phospholipid membrane bilayer with embedded proteins responsible for cellular recognition and membrane fusion. Thus, the Cystoviridae are akin to enveloped viruses which also use protein complexes embedded into their membrane for cellular recognition and membrane fusion. Examples of such viruses include the Retroviridae, Coronoviridae, Herpesviridae , and Orthomyxoviridae families. The binding specifics of Cystoviridae to the host outer membrane are unknown. Using Cystoviridae -OMV interaction we began to uncover the host requirements for binding Cystoviridae . The results presented determine that only lipid A and the core polysaccharide of LPS are required for Cystoviridae outer membrane binding.

Salvianolic acid A inhibits pseudorabies virus infection by directly inactivating the virus particle

BackgroundPseudorabies virus (PRV), a member of the family Herpesviridae, is responsible for significant economic losses in the pig industry and has recently been associated with human viral encephalitis, leading to severe neurological symptoms post-recovery. Despite the widespread impact of PRV, there are currently no approved effective drugs for treating PRV-related diseases in humans or pigs. Therefore, the exploration and discovery of safe and effective drugs for the prevention and treatment of PRV infection is of paramount importance. PurposeThe objective of this study is to screen and identify natural compounds with antiviral activity against PRV. MethodsFirst, we used a strain of PRV with green fluorescent protein (PRV-GFP) to screen a natural product chemical library to identify potential antiviral drugs. Next, we assessed the antiviral abilities of salvianolic acid A (SAA) in vitro using virus titer assay, qPCR, and IFA. We investigated the mechanisms of SAA's antiviral activity through viral attachment, internalization, inactivation, and nuclease digestion assay. Finally, we evaluated the efficacy of SAA in inactivating PRV using mice as the experimental subjects. ResultsThis study screened 206 natural compounds for anti-PRV activity in vitro, resulting in the identification of seven potential antiviral agents. Notably, SAA emerged as a promising candidate with significant anti-PRV activity. The mechanism of action may be that SAA can directly inactivate the virus by disrupting viral envelope. In vivo experiments have shown that pre-incubation of SAA and PRV can effectively inhibit the infectivity and pathogenicity of PRV in mice. ConclusionThis study offers valuable insights into the antiviral properties of SAA, potentially informing strategies for controlling PRV epidemics and treating related diseases in both humans and animals.

Transplacental Infections Associated with Macavirus in Aborted Bovine Fetuses.

The Macavirus genus, Gammaherpesvirinae subfamily, Herpesviridae family, contains ovine gammaherpesvirus 2 (OvGHV2), the cause of sheep-associated malignant catarrhal fever (SA-MCF). Members of the Macavirus genus associated with the development of malignant catarrhal fever (MCF) in their respective hosts share the 15A antigenic epitope, are conserved within the DNA polymerase gene and are collectively referred to as the malignant catarrhal fever virus (MCFV) complex. The ability of MCFV and/or OvGHV2 to produce abortions in ruminants is currently unknown, with little documentation of infections by these agents in bovine fetuses. This report presents the findings observed due to the detection of OvGHV2 DNA and MCFV tissue antigens in aborted bovine fetuses from southern Brazil. Four aborted bovine fetuses from three farms, located in a geographical region of Paraná State with elevated immunohistochemical (IHC) prevalence of MCFV tissue antigens, with gestational ages varying between 78 to 208 days were investigated. Significant gross and histopathological alterations were not observed in any of these fetuses. An IHC assay using the 15A-monoclonal antibody (15A-MAb), which is based on the 15A antigenic epitope of Macavirus, identified MCFV tissue antigens in multiple organs from two fetuses (#1 and #4); however, positive immunoreactivity to the 15A-MAb IHC assay was not detected in Fetus #2 and #3. Molecular testing amplified OvGHV2 DNA only from the myocardium and lungs of Fetus #1 that had positive intracytoplasmic immunoreactivity to the 15A-MAb IHC assay in these tissues. Furthermore, infections by Leptospira spp. were confirmed by molecular assays in fetuses #1, #3, and #4, while PCR detected Neospora caninum in the myocardium of Fetus #2. Additionally, molecular assays to identify well-known fetopathy agents of cattle, including bovine viral diarrhea virus, bovine alphaherpesvirus 1, Histophilus somni, and Listeria monocytogenes, did not amplify the nucleic acids of these pathogens. PCR assays to identify bovine gammaherpesvirus 6 (BoGHV6), another Macavirus known to infect cattle in Brazil, were unsuccessful. These findings confirmed that the 15A-MAb IHC assay can be efficiently used to detect MCFV antigens in organs of aborted bovine fetuses. The identification of MCFV antigens with the simultaneous detection of OvGHV2 DNA confirmed that Fetus #1 was infected by OvGHV2 and added to the few descriptions of this infection in aborted fetuses of ruminants worldwide. Moreover, the IHC detection of MCFV in multiple organs of Fetus #4, without the molecular detection of OvGHV2 or BoGHV6, may suggest that this fetus was infected by a Macavirus that was not previously diagnosed in cattle herds from Brazil. These findings strongly suggest that OvGHV2 and MCFV can produce transplacental infections in cattle.

Human herpesvirus 6 as the underestimated causative agent of seizure disorders in febrile children

Introduction and objective: The aim of the study was to analyse the clinical symptoms and laboratory abnormalities of seizure disorders in febrile children infected with pathogens from the Herpesviridae family – human herpesvirus 6 (HHV-6), human cytomegalovirus (HCMV), and Epstein–Barr virus (EBV). Materials and methods: A total of 75 children were included in the study, including 64 patients after a febrile seizure and 11 patients after an epileptic seizure triggered by infection. The control group consisted of 36 children with developmental delay. Routine inflammatory markers were analysed including C-reactive protein (CRP), procalcitonin (PCT), erythrocyte sedimentation rate (ESR), and white blood count (WBC). Pathogens were detected using standard diagnostic methods. Results: Compared to control group, median CRP and PCT were significantly higher in children with all types of febrile seizures, and ESR was significantly higher in children with simple and complex seizures. Most children with WBC below and above the normal range were children with simple febrile seizures plus and those with complex seizures, respectively. HHV-6 was detected in 33% of children. HCMV was found in 5%, and EBV in 4% of children. There was no significant correlation between children with and without primary HHV-6 infection regarding age, gender, febrile seizures type and first-time seizures, nor significant differences in inflammatory markers except for WBC. The difference between the number of children with three-day fever and those without rash was borderline significant (p = 0.06); children with primary HHV-6 infection without rash had more frequent first-time seizures (p = 0.04). Conclusions: The clinical course of seizure disorders and the intensity of the inflammatory reaction in children were mild. HHV-6 was the most common causative agent of fever and seizure disorders.

Management of Cytomegalovirus Infection in Allogeneic Hematopoietic Stem Cell Transplant Recipients

Cytomegalovirus (CMV) is a type of double-stranded deoxyribonucleic acid virus belonging to the herpesviridae family. Following a primary infection, the virus becomes latent in various types of white blood cells. Cytomegalovirus infection can remain latent or become active, especially in immunocompromised individuals, such as those undergoing hematopoietic stem cell transplantation (HSCT), where CMV reactivation can occur. In this context, CMV infection is common and associated with high rates of morbidity and mortality. Pneumonia is one of the most serious complications, with mortality rates exceeding 50%. Additionally, even in the absence of organ-specific disease, CMV infection is related to increased mortality unrelated to hematologic neoplasm recurrence. Given the frequency and severity of this infection in HSCT patients, it is crucial to implement effective strategies for monitoring, prevention, and treatment. This guideline was developed to identify patient groups that benefit from a systematic approach to CMV infection and to define the most appropriate strategy for each group. Monitoring CMV viral load in peripheral blood is crucial, especially in patients at moderate to high risk of active infection. Primary prophylaxis with letermovir (an antiviral drug) is recommended to reduce the incidence of active infection, especially in high-risk patients. Secondary prophylaxis with valganciclovir (antiviral drug) is recommended after an episode of active infection, while preemptive and disease treatment is based on monitoring viral load and clinical response. The aim of this guideline is to improve the approach to CMV infection in HSCT patients, ensuring an effective and safe preventive and therapeutic approach.

The antiherpetic and anti-inflammatory activity of the frog-derived peptide Hylin-a1.

The high incidence of virus-related infections and the large diffusion of drug-resistant pathogens stimulate the search and identification of new antiviral agents with a broad spectrum of action. Antivirals can be designed to act on a single target by interfering with a specific step in the viral lifecycle. On the contrary, antiviral peptides (AVPs) are known for acting on a wide range of viruses, with a diversified mechanism of action targeting virus and/or host cell. In the present study, we evaluated the antiviral potential of the peptide Hylin-a1 secreted by the frog Hypsiobas albopunctatus against members of the Herpesviridae family. The inhibitory capacity of the peptide was evaluated in vitro by plaque assays in order to understand the possible mechanism of action. The results were also confirmed by real-time PCR and Western blot evaluating the expression of viral genes. Hylin-a1 acts to block the herpetic infection interfering at the early stages of both herpes simplex virus type 1 (HSV-1) and type 2 infection. Its mechanism is mainly directed on the membrane, probably by damaging the viral envelope. The same effect was also observed against HSV-1 strains resistant to acyclovir. The data presented in this study, such as the increased activity of the peptide when combined to acyclovir, a weak hemolytic profile, an anti-inflammatory effect, and a tolerable half-life in serum, indicates Hylin-a1 as a novel antiherpetic molecule with promising potential in the clinical setting.

Characterization of Herpesviridae Family Members, BK Virus, and Adenovirus in Children and Adolescents with Nephrotic Syndrome.

A prospective study was conducted to determine the genome identification of the viruses Epstein-Barr (EBV), human cytomegalovirus (HCMV), human herpesvirus 6 (HHV-6 type A and type B) and 7 (HHV-7), polyomavirus (BKV), and human adenovirus (HAdV) in plasma and urine samples of pediatric patients with NS. A total of 35 patients aged 1 to 18 years with NS and under immunosuppressant drugs participated in the study. Plasma and urine samples were collected at regular intervals during a median follow-up of 266 days (range 133-595), and DNA was analyzed to detect the selected DNA viruses. Eleven patients (31.4%) had active virus infections, and patterns were classified as coinfection, recurrent, and consecutive. Of these, six patients (54.5%) presented viral coinfection, six (54.5%) viral recurrence, and seven patients (63.3%) had viral consecutive infection. Ten of the eleven patients with active infection had a proteinuria relapse (91%) and eight (72.7%) were hospitalized (p = 0.0022). Active HCMV infection was the most frequent infection and was observed in six patients (54.5%), three of the eleven patients (27.2%) had suspected HCMV disease in the gastrointestinal tract, and one had HHV-7 coinfection. The frequency of other infections was: 9% for HHV-6, 45.5% for BKV, 27.3% for HHV-7, 18.2% for EBV, and 18.2% for HAdV. viral infections, especially HCMV, can be an important cause of morbidity and nephrotic syndrome relapse in children.

Advancing Green Chemistry in Antiviral Therapeutics: A Comprehensive Review.

Cytomegalovirus (CMV) is a prevalent virus across the world that belongs to the family Herpesviridae but remains dormant in the body unless the immune system is compromised. In addition, when the bacterium is compromised without any health risks, the infection spreads from one person to another person through body fluids, such as saliva, blood, etc. Ganciclovir is an anti- viral medication used in treating viral infections, especially in the treatment of CMV in people with acquired immune deficiency syndrome and immunity at risk. The quality control of ganciclovir in industries is carried out by using anti-green solvents in large volumes; these solvents are not safe in consideration of environmental factors and analysts. Also, the waste generation by these solvents causes hazardous effects on the environment. Further, using 12 green analytical chemistry principles promotes the awareness of analytical judgments among the research groups. It is a revolutionary step in the analytical field to enhance the safety of the environment, and analysts, apart from safety, help to control waste production and conserve energy-reducing occupational hazards. Many works have been carried out for the quality control of ganciclovir using different solvents, such as acetonitrile, methanol, etc. Despite this, there are no existing methods with green solvents or procedures to reduce energy and waste generation. Therefore, the purpose of this review is to understand the drug profile of ganciclovir and the methods developed.

MARCH1 and MARCH2 inhibit pseudorabies virus replication by trapping the viral cell-to-cell fusion complex in trans-Golgi network

The membrane-associated RING-CH (MARCH) family of proteins are members of the E3 ubiquitin ligase family and are essential for a variety of biological functions. Currently, MARCH proteins are discovered to execute antiviral functions by directly triggering viral protein degradation or blocking the furin cleavage of viral class I fusion proteins. Here, we report a novel antiviral mechanism of MARCH1 and MARCH2 (MARCH1/2) in the replication of Pseudorabies virus (PRV), a member of the Herpesviridae family. We discovered MARCH1/2 restrict PRV replication at the cell-to-cell fusion step. Furthermore, MARCH1/2 block gB cleavage, and this is dependent on their E3 ligase activity. Interestingly, the blocking of gB cleavage by MARCH1/2 does not contribute to their antiviral activity in vitro. We discovered that MARCH1/2 are associated with the cell-to-cell fusion complex of gB, gD, gH, and gL and trap these viral proteins in the trans-Golgi network (TGN) rather than degrading them. Overall, we conclude that MARCH1/2 inhibit PRV by trapping the viral cell-to-cell fusion complex in TGN.

Varicella-zoster virus-related neurological complications: From infection to immunomodulatory therapies.

The Varicella-zoster virus (VZV), classified as a neurotropic member of the Herpesviridae family, exhibits a characteristic pathogenicity, predominantly inducing varicella, commonly known as chickenpox, during the initial infectious phase, and triggering the reactivation of herpes zoster, more commonly recognized as shingles, following its emergence from a latent state. The pathogenesis of VZV-associated neuroinflammation involves a complex interplay between viral replication within sensory ganglia and immune-mediated responses that contribute to tissue damage and dysfunction. Upon primary infection, VZV gains access to sensory ganglia, establishing latent infection within neurons. During reactivation, the virus can spread along sensory nerves, triggering a cascade of inflammatory mediators, chemokines, and immune cell infiltration in the affected neural tissues. The role of both adaptive and innate immune reactions, including the contributions of T and B cells, macrophages, and dendritic cells, in orchestrating the immune-mediated damage in the central nervous system is elucidated. Furthermore, the aberrant activation of the natural defence mechanism, characterised by the dysregulated production of immunomodulatory proteins and chemokines, has been implicated in the pathogenesis of VZV-induced neurological disorders, such as encephalitis, myelitis, and vasculopathy. The intricate balance between protective and detrimental immune responses in the context of VZV infection emphasises the necessity for an exhaustive comprehension of the immunopathogenic mechanisms propelling neuroinflammatory processes. Despite the availability of vaccines and antiviral therapies, VZV-related neurological complications remain a significant concern, particularly in immunocompromised individuals and the elderly. Elucidating these mechanisms might facilitate the emergence of innovative immunomodulatory strategies and targeted therapies aimed at mitigating VZV-induced neuroinflammatory damage and improving clinical outcomes. This comprehensive understanding enhances our grasp of viral pathogenesis and holds promise for pioneering therapeutic strategies designed to mitigate the neurological ramifications of VZV infections.

Production and characterization of biologicals for disease diagnosis and pathological evaluation of elephant endotheliotropic herpesvirus (EEHV)

Elephant endotheliotropic herpesviruses (EEHV) belong to the family Herpesviridae and cause a highly fatal hemorrhagic infection in elephants. EEHV poses a global threat to the already endangered elephant population. Since EEHV is a non-cultivable virus, there is a scarcity of specific diagnostics, therapeutics, and vaccines. In this study, our objective was to develop biologicals for diagnosis and pathological studies against the most prevalent EEHV1A/1B. We expressed two truncated fragments of the DNA polymerase, glycoprotein B (gB), and glycoprotein (gL) of EEHV in the prokaryotic system. Hyperimmune serum against the purified antigens was raised in rabbits and guinea pigs. We validated the reactivity of this hyperimmune serum using western blotting, ELISA, and immune-histochemistry on known positive infected tissues. Samples collected from 270 animals across various states in India were evaluated with these biologicals. The raised antibodies successfully demonstrated virus in immune-cytochemistry. Additionally, all known positive samples consistently exhibited significant inhibition in the OD values when used in the competitive format of ELISA across all four antigens when compared to the serum collected from known negative animals. An apparent sero-prevalence of 10 % was observed in the randomly collected samples. In summary, our study successfully developed and validated biologicals that will be invaluable for EEHV diagnosis and control.

The Effects of Endosomal Toll-like Receptor Inhibitors in an EBV DNA-Exacerbated Inflammatory Bowel Disease Mouse Model.

Epstein-Barr virus (EBV), a Herpesviridae family member, is associated with an increased risk of autoimmune disease development in the host. We previously demonstrated that EBV DNA elevates levels of the pro-inflammatory cytokine IL-17A and that inhibiting Toll-like receptor (TLR) 3, 7, or 9 reduces its levels. Moreover, this DNA exacerbated colitis in a mouse model of inflammatory bowel disease (IBD). In the study at hand, we examined whether inhibition of TLR3, 7, or 9 alleviates this exacerbation. Mice were fed 1.5% dextran sulfate sodium (DSS) water and administered EBV DNA. Then, they were treated with a TLR3, 7, or 9 inhibitor or left untreated. We also assessed the additive impact of combined inhibition of all three receptors. Mice that received DSS, EBV DNA, and each inhibitor alone, or a combination of inhibitors, showed significant improvement. They also had a decrease in the numbers of the pathogenic colonic IL-17A+IFN-γ+ foci. Inhibition of all three endosomal TLR receptors offered no additive benefit over administering a single inhibitor. Therefore, inhibition of endosomal TLRs reduces EBV DNA exacerbation of mouse colitis, offering a potential approach for managing IBD patients infected with EBV.

Association between cytomegalovirus infection and neurological disorders: A systematic review.

Cytomegalovirus (CMV) belongs to the Herpesviridae family and is also known as human herpesvirus type 5. It is a common virus that usually doesn't cause any symptoms in healthy individuals. However, once infected, the virus remains in the host's body for life and can reactivate when the host's immune system weakens. This virus has been linked to several neurological disorders, including Alzheimer's disease, Parkinson's disease, Autism spectrum disorder, Huntington's disease (HD), ataxia, Bell's palsy (BP), and brain tumours, which can cause a wide range of symptoms and challenges for those affected. CMV may influence inflammation, contribute to brain tissue damage, and elevate the risk of moderate-to-severe dementia. Multiple studies suggest a potential association between CMV and ataxia in various conditions, including Guillain-Barré syndrome, chronic inflammatory demyelinating polyneuropathy, acute cerebellitis, etc. On the other hand, the evidence regarding CMV involvement in BP is conflicting, and also early indications of a link between CMV and HD were challenged by subsequent research disproving CMV's presence. This systematic review aims to comprehensively investigate any link between the pathogenesis of CMV and its potential role in neurological disorders and follows the preferred reporting items for systematic review and meta-analysis checklist. Despite significant research into the potential links between CMV infection and various neurological disorders, the direct cause-effect relationship is not fully understood and several gaps in knowledge persist. Therefore, continued research is necessary to gain a better understanding of the role of CMV in neurological disorders and potential treatment avenues.