Boosting Vaccine Response in Autoimmune Rheumatic Disease Patients With Inadequate Seroconversion: An Analysis of the Immunogenicity of Vector-Based and Inactivated Vaccines.

Background: An additional dose of COVID-19 vaccine is being offered to vaccinated people, especially those immunocompromised. The most widely available vaccines in India are the adenoviral vector-based AZD1222 (ChAdOx1 nCoV-19) and the heat-inactivated (BBV152). This study investigated the efficacy of both vaccines in patients with autoimmune rheumatic diseases (AIRD).

The burden of dengue and force of infection among children in Kerala, India; seroprevalence estimates from Government of Kerala-WHO Dengue study.

Background: Dengue shows high geographic heterogeneity within and across endemic countries. In the context of increasing burden and predicted outbreaks due to climate change, understanding the heterogeneity will enable us to develop region specific targeted interventions, including vaccination. World Health Organisation (WHO) suggests standard methodologies to study the burden and heterogeneity at national and subnational levels.

Fingolimod (FTY720), an FDA-approved sphingosine 1-phosphate (S1P) receptor agonist, restores endothelial hyperpermeability in cellular and animal models of dengue virus serotype 2 infection.

Extensive vascular leakage and shock is a major cause of dengue-associated mortality. At present, there are no specific treatments available. Sphingolipid pathway is a key player in the endothelial barrier integrity; and is mediated through the five sphingosine-1-phosphate receptors (S1PR1-S1PR5).

Targeted Sanger Sequencing of a Cluster of COVID-19 Cases in the Surgical ICU of a Non-COVID Hospital: Lessons Learned.

Small clusters of infection due to SARS-CoV-2 in a non-COVID-19 healthcare facility can disrupt services. Here, we investigated a cluster of SARS-CoV-2 cases by targeted Sanger sequencing and clinical epidemiological methods in a non-COVID-19 super-specialty hospital. Epidemiological data were collected in a blinded manner using a proforma to find the risk factors associated with infection.

A high-throughput screening system for SARS-CoV-2 entry inhibition, syncytia formation and cell toxicity.

Background: The entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the host cell is mediated through the binding of the SARS-CoV-2 Spike protein via the receptor binding domain (RBD) to human angiotensin-converting enzyme 2 (hACE2). Identifying compounds that inhibit Spike-ACE2 binding would be a promising and safe antiviral approach against COVID-19.

Methods: In this study, we used a BSL-2 compatible replication-competent vesicular stomatitis virus (VSV) expressing Spike protein of SARS-CoV-2 with eGFP reporter system (VSV-eGFP-SARS-CoV-2) in a recombinant permissive cell system for high-throughput screening of viral entry blockers.

Host Factor Nucleophosmin 1 (NPM1/B23) Exerts Antiviral Effects against Chikungunya Virus by Its Interaction with Viral Nonstructural Protein 3.

Chikungunya virus (CHIKV) hijacks host cell machinery to support its replication. Nucleophosmin 1 (NPM1/B23), a nucleolar phosphoprotein, is one of the host proteins known to restrict CHIKV infection; however, the mechanistic details of the antiviral role of NPM1 are not elucidated. It was seen in our experiments that the level of NPM1 expression affected the expression levels of interferon-stimulated genes (ISGs) that play antiviral roles in CHIKV infection, such as , , , and , indicating that one of the antiviral mechanisms could be through modulation of interferon-mediated pathways.

Higher-temperature-adapted dengue virus serotype 2 strain exhibits enhanced virulence in AG129 mouse model.

The factors that drive dengue virus (DENV) evolution, and selection of virulent variants are yet not clear. Higher environmental temperature shortens DENV extrinsic incubation period in mosquitoes, increases human transmission, and plays a critical role in outbreak dynamics. In the present study, we looked at the effect of temperature in altering the virus virulence.

Ethyl palmitate, an anti-chikungunya virus principle from Sauropus androgynus, a medicinal plant used to alleviate fever in ethnomedicine.

Ethnopharmacological Relevance: Sauropus androgynus is a medicinal shrub used for the treatment of fever in ethnomedical traditions in various Southeast Asian countries.

Aim Of The Study: This study was aimed to identify antiviral principles from S. androgynus against Chikungunya virus (CHIKV), a major mosquito-borne pathogen that re-emerged in the last decade, and to unravel their mechanism of action.

Generation of a Live-Attenuated Strain of Chikungunya Virus from an Indian Isolate for Vaccine Development.

Chikungunya virus (CHIKV) re-emergence in the last decade has resulted in explosive epidemics. Along with the classical symptoms of fever and debilitating arthralgia, there were occurrences of unusual clinical presentations such as neurovirulence and mortality. These generated a renewed global interest to develop prophylactic vaccines.

Breakthrough infection with SARS-CoV-2 delta variant in old-age homes in a Southern District of Kerala, India.

Background: The incidence of breakthrough infection with the emergence of new variants of concern of SARS-CoV-2 is posing a threat, and it is pertinent to understand the role of vaccines in protecting the elderly and people with comorbidities.

Objective: The present study was undertaken to understand the natural history of SARS-CoV-2 infection in a closed cohort of the elderly population in an old-age home who have received two doses of COVID-19 vaccination. The study has also undertaken genomic sequencing to identify SARS-CoV-2 variants of concern from an academic perspective.

A rapid bead-based assay for screening of SARS-CoV-2 neutralizing antibodies.

Quantitative determination of neutralizing antibodies against Severe Acute Respiratory Syndrome Corona Virus-2 (SARS-CoV-2) is paramount in immunodiagnostics, vaccine efficacy testing, and immune response profiling among the vaccinated population. Cost-effective, rapid, easy-to-perform assays are essential to support the vaccine development process and immunosurveillance studies. We describe a bead-based screening assay for S1-neutralization using recombinant fluorescent proteins of hACE2 and SARS-CoV2-S1, immobilized on solid beads employing nanobodies/metal-affinity tags.

Immune profile and responses of a novel dengue DNA vaccine encoding an EDIII-NS1 consensus design based on Indo-African sequences.

The ongoing COVID-19 pandemic highlights the need to tackle viral variants, expand the number of antigens, and assess diverse delivery systems for vaccines against emerging viruses. In the present study, a DNA vaccine candidate was generated by combining in tandem envelope protein domain III (EDIII) of dengue virus serotypes 1-4 and a dengue virus (DENV)-2 non-structural protein 1 (NS1) protein-coding region. Each domain was designed as a serotype-specific consensus coding sequence derived from different genotypes based on the whole genome sequencing of clinical isolates in India and complemented with data from Africa.

Targeting cap-dependent translation to inhibit Chikungunya virus replication: selectivity of p38 MAPK inhibitors to virus-infected cells due to autophagy-mediated down regulation of phospho-ERK.

The 5' capped, message-sense RNA genome of Chikungunya virus (CHIKV) utilizes the host cell machinery for translation. Translation is regulated by eIF2 alpha at the initiation phase and by eIF4F at cap recognition. Translational suppression by eIF2 alpha phosphorylation occurs as an early event in many alphavirus infections.

Binding of alpha-fodrin to gamma-tubulin accounts for its role in the inhibition of microtubule nucleation.

Non-erythroid spectrin or fodrin is present as part of the γ-tubulin ring complex (γ-TuRC) in brain tissue and brain derived cells. Here, we show that fodrin, which is otherwise known for providing structural support to the cell membrane, interacts directly with γ-tubulin within the γ-TuRC through a GRIP2-like motif. Turbidometric analysis of microtubule polymerization with nucleation-potent γ-TuRC isolated from HEK-293 cells that lack fodrin and the γ-TuRC from goat brain that contains fodrin shows inefficiency of the latter to promote nucleation.

Dengue virus or NS1 protein induces trans-endothelial cell permeability associated with VE-Cadherin and RhoA phosphorylation in HMEC-1 cells preventable by Angiopoietin-1.

A transient increase in trans-endothelial cell permeability in dengue patients leads to vascular leakage and shock syndrome. Here, we analysed the molecular mechanisms that cause permeability changes in human dermal microvascular endothelial cells (HMEC-1) using a direct dengue virus (DENV) infection model or treatment with NS1, a secreted DENV non-structural protein. In HMEC-1 cells, both treatments increase permeability with a concordant increase in the secretion of angiopoietin-2 (Ang-2).

Preparation of Recombinant Alphaviruses for Functional Studies of ADP-Ribosylation.

Recently we characterized the mono(ADP-ribosyl) hydrolase (MAR hydrolase) activity of the macrodomain of nonstructural protein 3 (nsP3) of chikungunya virus. Using recombinant viruses with targeted mutations in the macrodomain, we demonstrated that hydrolase function is important for viral replication in cultured neuronal cells and for neurovirulence in mice. Here, we describe the general cell culture and animal model infection protocols for alphaviruses and the technical details for biochemical characterization of the MAR hydrolase activity of nsP3 mutants and the preparation of recombinant viruses incorporating those mutations through site-directed mutagenesis of an infectious cDNA virus clone.

Sphingolipid signaling modulates trans-endothelial cell permeability in dengue virus infected HMEC-1 cells.

Dengue has emerged as a major mosquito-borne disease in the tropics and subtropics. In severe dengue, enhanced microvascular endothelial permeability leads to plasma leakage. Direct dengue virus (DENV) infection in human microvascular endothelial cells (HMEC-1) can enhance trans-endothelial leakage.

Interferon regulated gene (IRG) expression-signature in a mouse model of chikungunya virus neurovirulence.

Interferon regulated genes (IRGs) are critical in controlling virus infections. Here, we analyzed the expression profile of IRGs in the brain tissue in a mouse model of chikungunya virus (CHIKV) neurovirulence. Neurovirulence is one of the newer complications identified in disease caused by re-emerging strains of CHIKV, an alphavirus with positive-strand RNA in the Togaviridae family.

Nucleophosmin (NPM1)/B23 in the Proteome of Human Astrocytic Cells Restricts Chikungunya Virus Replication.

Chikungunya virus (CHIKV), a positive-stranded RNA virus, can cause neurological complications by infecting the major parenchymal cells of the brain such as neurons and astrocytes. A proteomic analysis of CHIKV-infected human astrocytic cell line U-87 MG revealed tight functional associations among the modulated proteins. The predominant cellular pathways involved were of transcription-translation machinery, cytoskeletol reorganization, apoptosis, ubiquitination, and metabolism.

Comparative whole genome analysis of dengue virus serotype-2 strains differing in trans-endothelial cell leakage induction in vitro.

The role of genetic differences among dengue virus (DENV) in causing increased microvascular permeability is less explored. In the present study, we compared two closely related DENV serotype-2 strains of Cosmopolitan genotype for their in vitro infectivity phenotype and ability to induce trans-endothelial leakage. We found that these laboratory strains differed significantly in infecting human microvascular endothelial cells (HMEC-1) and hepatocytes (Huh7), two major target cells of DENV in in vivo infections.

ADP-ribosylhydrolase activity of Chikungunya virus macrodomain is critical for virus replication and virulence.

Chikungunya virus (CHIKV), an Old World alphavirus, is transmitted to humans by infected mosquitoes and causes acute rash and arthritis, occasionally complicated by neurologic disease and chronic arthritis. One determinant of alphavirus virulence is nonstructural protein 3 (nsP3) that contains a highly conserved MacroD-type macrodomain at the N terminus, but the roles of nsP3 and the macrodomain in virulence have not been defined. Macrodomain is a conserved protein fold found in several plus-strand RNA viruses that binds to the small molecule ADP-ribose.

Re-emergence of dengue virus serotype 2 strains in the 2013 outbreak in Nepal.

Background & Objectives: Epidemiological interventions and mosquito control are the available measures for dengue control. The former approach uses serotype and genetic information on the circulating virus strains. Dengue has been frequently reported from Nepal, but this information is mostly lacking.

Correlation of phylogenetic clade diversification and in vitro infectivity differences among Cosmopolitan genotype strains of Chikungunya virus.

Cosmopolitan genotypes of Chikungunya virus caused the large-scale febrile disease outbreaks in the last decade in Asian and African continents. Molecular analyses of these strains had revealed significant genetic diversification and occurrence of novel mosquito-adaptive mutations. In the present study we looked into whether the genetic diversification has implications in the infectivity phenotype.

Phylogenetic study reveals co-circulation of Asian II and Cosmopolitan genotypes of Dengue virus serotype 2 in Nepal during 2013.

The re-emergence of dengue virus in Nepal and the recent widespread disease epidemics of unprecedented magnitude have raised a great public health concern. There are very few reports on Dengue virus (DENV) strains circulating in the country, especially at the molecular phylogenetics level. In this study, clinical samples from an outbreak in Nepal in 2013, which were positive for DENV serotype 2, were characterized by targeted genome sequencing.

High throughput proteomic analysis and a comparative review identify the nuclear chaperone, Nucleophosmin among the common set of proteins modulated in Chikungunya virus infection.

Unlabelled: Global re-emergence of Chikungunya virus (CHIKV) has renewed the interest in its cellular pathogenesis. We subjected CHIKV-infected Human Embryo Kidney cells (HEK293), a widely used cell-based system for CHIKV infection studies, to a high throughput expression proteomics analysis by Liquid Chromatography-tandem mass spectrometry. A total of 1047 differentially expressed proteins were identified in infected cells, consistently in three biological replicates.