Publications by authors named "Hae Ji Kang"

Protective efficacy assessment of toxoplasmosis vaccines, at least at the preclinical level, frequently involves lethal dose challenge infection. Nonetheless, their efficacies remain largely unexplored against low infection doses which better reflects how humans become infected in the real world. In this study, we compared the immunity elicited in mice that were heterologously immunized with recombinant baculovirus and virus-like particles expressing either the cyst wall protein (CST1) or microneme protein 8 (MIC8) of Toxoplasma gondii (T.

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Lactic acid bacteria (LAB) are probiotic microorganisms widely used for their health benefits in the food industry. However, recent concerns regarding their safety have highlighted the need for comprehensive safety assessments. In this study, we aimed to evaluate the safety of IDCC 3601, isolated from homemade plain yogurt, via genomic, phenotypic, and toxicity-based analyses.

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To evaluate the protective efficacy induced by heterologous immunization with recombinant baculoviruses or virus-like particles targeting the CST1 and ROP18 antigens of .: Recombinant baculovirus and virus-like particle vaccines expressing CST1 or ROP18 antigens were developed to evaluate protective immunity in mice upon challenge infection with 450 (ME49). Immunization with CST1 or ROP18 vaccines induced similar levels of -specific IgG and IgA responses.

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Article Synopsis
  • Immunocompromised individuals face a higher risk of prolonged SARS-CoV-2 infections and severe COVID-19, raising concerns about the effectiveness of late-onset antiviral treatments.
  • In a study using an immunocompromised mouse model, it was found that early treatments like nirmatrelvir/ritonavir (paxlovid) or molnupiravir were only moderately effective, while the experimental drug 4'-fluorouridine (4'-FlU) showed significant benefits in reducing viral load.
  • Late-onset direct-acting antiviral (DAA) therapies were shown to effectively shorten the duration of viral replication in immunocompromised hosts, suggesting potential clinical applications to reduce severe disease risks in vulnerable
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Dengue virus (DENV) infection is a public health concern in several countries and is associated with severe diseases, such as dengue hemorrhagic fever and dengue shock syndrome. DENVs are transmitted to humans via the bites of infected Aedes mosquitoes, and no antiviral therapeutics are currently available. In this work, we aimed to identify antiviral drugs against DENV type 2 (DENV2) infections and selected pimecrolimus as a potential antiviral drug candidate.

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Malaria is a global disease affecting a large portion of the world's population. Although vaccines have recently become available, their efficacies are suboptimal. We generated virus-like particles (VLPs) that expressed either apical membrane antigen 1 (AMA1) or microneme-associated antigen (MIC) of Plasmodium berghei and compared their efficacy in BALB/c mice.

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Unlabelled: The immunocompromised are at high risk of prolonged SARS-CoV-2 infection and progression to severe COVID-19. However, efficacy of late-onset direct-acting antiviral (DAA) therapy with therapeutics in clinical use and experimental drugs to mitigate persistent viral replication is unclear. In this study, we employed an immunocompromised mouse model, which supports prolonged replication of SARS-CoV-2 to explore late-onset treatment options.

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To develop an effective universal vaccine against antigenically different influenza viruses. We generated influenza virus-like particles (VLPs) expressing the H1 and H3 antigens with or without M2e5x. VLP-induced immune responses and crossprotection against H1N1, H3N2 or H5N1 viruses were assessed to evaluate their protective efficacy.

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Measles cases have surged pre-COVID-19 and the pandemic has aggravated the problem. Most measles-associated morbidity and mortality arises from destruction of pre-existing immune memory by measles virus (MeV), a paramyxovirus of the morbillivirus genus. Therapeutic measles vaccination lacks efficacy, but little is known about preserving immune memory through antivirals and the effect of respiratory disease history on measles severity.

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Pre-existing or rapidly emerging resistance of influenza viruses to approved antivirals makes the development of novel therapeutics to mitigate seasonal influenza and improve preparedness against future influenza pandemics an urgent priority. We have recently identified the chain-terminating broad-spectrum nucleoside analog clinical candidate 4'-fluorouridine (4'-FlU) and demonstrated oral efficacy against seasonal, pandemic, and highly pathogenic avian influenza viruses in the mouse and ferret model. Here, we have resistance-profiled 4'-FlU against a pandemic A/CA/07/2009 (H1N1) (CA09).

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Susceptibility to respiratory virus infections (RVIs) varies widely across individuals. Because the gut microbiome impacts immune function, we investigated the influence of intestinal microbiota composition on RVI and determined that segmented filamentous bacteria (SFB), naturally acquired or exogenously administered, protected mice against influenza virus (IAV) infection. Such protection, which also applied to respiratory syncytial virus and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was independent of interferon and adaptive immunity but required basally resident alveolar macrophages (AMs).

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Toxoplasma gondii infections are primarily diagnosed by serological assays, whereas molecular and fluorescence-based techniques are garnering attention for their high sensitivity in detecting these infections. Nevertheless, each detection method has its limitations. The toxoplasmosis detection capabilities of most of the currently available methods have not been evaluated under identical experimental conditions.

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Unlabelled: Pre-existing or rapidly emerging resistance of influenza viruses to approved antivirals makes the development of novel therapeutics to mitigate seasonal influenza and improve preparedness against future influenza pandemics an urgent priority. We have recently identified the chain-terminating broad-spectrum nucleoside analog clinical candidate 4'-fluorouridine (4'-FlU) and demonstrated oral efficacy against seasonal, pandemic, and highly pathogenic avian influenza viruses in the mouse and ferret model. Here, we have resistance-profiled 4'-FlU against a pandemic A/CA/07/2009 (H1N1) (CA09).

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Unlabelled: Susceptibility to respiratory virus infections (RVIs) varies widely across individuals. Because the gut microbiome impacts immune function, we investigated the influence of intestinal microbiota composition on RVI and determined that segmented filamentous bacteria (SFB), naturally acquired or exogenously administered, protected mice against influenza virus (IAV) infection. Such protection, which also applied to respiratory syncytial virus and SARS-CoV-2, was independent of interferon and adaptive immunity but required basally resident alveolar macrophages (AM).

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Toxoplasma gondii host cellular invasion factors such as the rhoptry proteins, micronemal antigens, or other subcellular compartment proteins have shown limited vaccine efficacies. T. gondii cyst wall protein (CST1) as a cyst persistence factor is critical for cyst wall integrity and bradyzoite persistence.

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Article Synopsis
  • Influenza outbreaks cause significant health issues and economic challenges, highlighting the need for new antiviral treatments to combat both seasonal infections and potential pandemics from avian influenza viruses.
  • The study investigates the effectiveness of the nucleoside analog 4'-Fluorouridine (4'-FlU) against various influenza A and B viruses, demonstrating its strong inhibitory action and unique mechanism of targeting the influenza virus polymerase.
  • Administering 4'-FlU orally in animal models showed promising results, with rapid cessation of virus spread in ferrets and complete survival in mice after lethal infections, indicating its potential as a candidate for treating seasonal and pandemic influenza.
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Toxoplasmosis diagnosis predominantly relies on serology testing via enzyme-linked immunosorbent assay (ELISA), but these results are highly variable. Consequently, various antigens are being evaluated to improve the sensitivity and specificity of toxoplasmosis serological diagnosis. Here, we generated virus-like particles displaying AMA1 of and evaluated their diagnostic potential.

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Recombinant vaccinia viruses (rVV) are effective antigen delivery vectors and are researched widely as vaccine platforms against numerous diseases. Apical membrane antigen 1 (AMA1) is one of the candidate antigens for malaria vaccines but rising concerns regarding its genetic diversity and polymorphism have necessitated the need to search for an alternative antigen. Here, we compare the efficacies of the rVV vaccines expressing either AMA1 or microneme protein (MIC) of in mice.

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Heterologous immunization is garnering attention as a promising strategy to improve vaccine efficacy. Vaccines based on recombinant baculovirus (rBV) and virus-like particle (VLP) are safe for use, but heterologous immunization studies incorporating these two vaccine platforms remain unreported to date. Oral immunization is the simplest, most convenient, and safest means for mass immunization.

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Heterologous prime-boost immunization regimens using various vaccine platforms demonstrated promising results against infectious diseases. Here, mice were sequentially immunized with the recombinant baculovirus (rBV), virus-like particle (VLP), and recombinant vaccinia virus (rVV) vaccines expressing the apical membrane antigen 1 (AMA1) for protective efficacy evaluation. The rBV_V_rVV heterologous immunization regimen elicited high levels of parasite-specific IgG, IgG2a, and IgG2b antibody responses in sera.

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Both sublingual (SL) and oral vaccine administration modalities are convenient, easy, and safe. Here, we have investigated the differences in vaccine efficacy that are induced by oral and sublingual immunization with live influenza virus (A/Hong Kong/1/1968, H3N2) in mice. Intranasally administering a lethal dose of the influenza virus resulted in the deaths of the mice, whereas viral replication in the lungs did not occur upon SL or oral administration.

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The mismatch between the circulating influenza B virus (IBV) and the vaccine strain contributes to the rapid emergence of IBV infection cases throughout the globe, which necessitates the development of effective vaccines conferring broad protection. Here, we generated influenza B virus-like particle (VLP) vaccines expressing hemagglutinin, neuraminidase, or both antigens derived from the influenza B virus (B/Washington/02/2019 (B/Victoria lineage)-like virus, B/Phuket/3073/2013 (B/Yamagata lineage)-like virus. We found that irrespective of the derived antigen lineage, immunizing mice with the IBV VLPs significantly reduced lung viral loads, minimized bodyweight loss, and ensured 100% survival upon Victoria lineage virus B/Colorado/06/2017 challenge infection.

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