Publications by authors named "Ritika Khatri"

Effective antiviral drugs are essential to combat COVID-19 and future pandemics. Although many compounds show antiviral activity, only a few retain effectiveness against SARS-CoV-2. Here, we show that berbamine (Berb) is effective against SARS-CoV, MER-CoV, SARS-CoV-2 and its variants, including the XBB.

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Middle East respiratory syndrome coronavirus (MERS-CoV) is a lethal beta-coronavirus that emerged in 2012. The virus is part of the WHO blueprint priority list with a concerning fatality rate of 35%. Scientific efforts are ongoing for the development of vaccines, anti-viral and biotherapeutics, which are majorly directed toward the structural spike protein.

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Pathogenic infections cause thymic atrophy, perturb thymic T-cell development, and alter immunological response. Previous studies reported dysregulated T-cell function and lymphopenia in coronavirus disease-19 (COVID-19). However, immunopathological changes in the thymus associated with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection have not been elucidated.

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Dengue virus infection in humans ranges from asymptomatic infection to severe infection, with ∼2.5 % overall disease fatality rate. Evidence of neurological manifestations is seen in the severe form of the disease, which might be due to the direct invasion of the viruses into the CNS system but is poorly understood.

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The COVID-19 pandemic caused by SARS-CoV-2, lead to mild to severe respiratory illness and resulted in 6.9 million deaths worldwide. Although vaccines are effective in preventing COVID-19, they may not be sufficient to protect immunocompromised individuals from this respiratory illness.

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A recently emerged sub-lineage of Omicron, BA.5, together with BA.4, caused a fifth wave of coronavirus disease (COVID-19) in South Africa and subsequently emerged as a predominant strain globally due to its high transmissibility.

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Unlabelled: The spike (S) glycoprotein of the SARS-CoV-2 virus binds to the host cell receptor and promotes the virus's entry into the target host cell. This interaction is primed by host cell proteases like furin and TMPRSS2, which act at the S1/S2 and S2´ cleavage sites, respectively. Both cleavage sites have serine or proline residues flanking either the single or polybasic region and were found to be conserved in coronaviruses.

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Immunogens mimicking the native-like structure of surface-exposed viral antigens are considered promising vaccine candidates. Influenza viruses are important zoonotic respiratory viruses with high pandemic potential. Recombinant soluble hemagglutinin (HA) glycoprotein-based protein subunit vaccines against Influenza have been shown to induce protective efficacy when administered intramuscularly.

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The SARS-CoV-2 virus has been rapidly evolving over the time and the genetic variation has led to the generation of Variants of Concerns (VoC), which have shown increased fitness. These VoC viruses contain the key mutations in the spike protein which have allowed better survival and evasion of host defense mechanisms. The D614G mutation in the spike domain is found in the majority of VoC; additionally, the P681R/H mutation at the S1/S2 furin cleavage site junction is also found to be highly conserved in major VoCs; Alpha, Delta, Omicron, and its' current variants.

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The newly emerging SARS-CoV-2 variants are potential threat and posing new challenges for medical intervention due to high transmissibility and escaping neutralizing antibody (NAb) responses. Many of these variants have mutations in the receptor binding domain (RBD) of SARS-CoV-2 spike protein that interacts with the host cell receptor. Rapid mutation in the RBD through natural selection to improve affinity for host receptor and antibody pressure from vaccinated or infected individual will greatly impact the presently adopted strategies for developing interventions.

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Japanese encephalitis virus (JEV) is a single-stranded positive-sense RNA virus belonging to the Flaviviridae family. The JEV is the leading cause of viral encephalitis in children and the elderly which is spread by mosquitoes. JEV infection has been established in different animal models such as mouse, hamster, guinea pig, swine, rat, monkey, rabbit by using the different routes of inoculations.

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Nanoparticles-based multivalent antigen display has the capability of mimicking natural virus infection characteristics, making it useful for eliciting potent long-lasting immune response. Several vaccines are developed against global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However these subunit vaccines use mammalian expression system, hence mass production with rapid pace is a bigger challenge.

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The COVID-19 pandemic caused by SARS-CoV-2 has a significant burden on the economy and healthcare around the world. Vaccines are the most effective tools to fight infectious diseases by containing the spread of the disease. The current vaccines against SARS-CoV-2 are mostly based on the spike protein of SARS-CoV-2, which is large and has many immune-dominant non-neutralizing epitopes that may effectively skew the antibody response towards non-neutralizing antibodies.

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The spike protein of the SARS-CoV-2 virus is the foremost target for the designing of vaccines and therapeutic antibodies and also acts as a crucial antigen in the assessment of COVID-19 immune responses. The enveloped viruses; such as SARS-CoV-2, Human Immunodeficiency Virus-1 (HIV-1) and influenza, often hijack host-cell glycosylation pathways and influence pathobiology and immune selection. These glycan motifs can lead to either immune evasion or viral neutralization by the production of cross-reactive antibodies that can lead to antibody-dependent enhancement (ADE) of infection.

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The route of administration of a therapeutic agent has a substantial impact on its success. Therapeutic antibodies are usually administered systemically, either directly by intravenous route, or indirectly by intramuscular or subcutaneous injection. However, treatment of diseases contained within a specific tissue necessitates a better alternate route of administration for targeting localised infections.

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COVID-19 pandemic has caused severe disruption of global health and devastated the socio-economic conditions all over the world. The disease is caused by SARS-CoV-2 virus that belongs to the family of Coronaviruses which are known to cause a wide spectrum of diseases both in humans and animals. One of the characteristic features of the SARS-CoV-2 virus is the high reproductive rate (R) that results in high transmissibility of the virus among humans.

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Natural variation separates Epstein-Barr virus (EBV) into type 1 and type 2 strains. Type 2 EBV is less transforming in vitro due to sequence differences in the EBV transcription factor EBNA2. This correlates with reduced activation of the EBV oncogene LMP1 and some cell genes.

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