Publications by authors named "Hongtae Park"

The nature of the effector and memory T cell response in the lungs following acute SARS-CoV-2 infections remains largely unknown. To define the pulmonary T-cell response to COVID-19, we compared effector and memory T-cell responses to SARS-CoV-2 and influenza A virus (IAV) in mice. Both viruses elicited potent effector T cell responses in lungs, but memory T cells showed exaggerated contraction in SARS-CoV-2-infected mice.

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Unlabelled: Pre-existing T-cell responses have been linked to reduced disease severity and better clinical outcomes during the 2009 influenza pandemic and the recent COVID-19 pandemic. We hypothesized that diversifying T-cell responses, particularly targeting conserved viral proteins such as the influenza A virus (IAV) nucleoprotein (NP), could protect against both epidemic and pandemic IAV strains. To test this, we created a mosaic nucleoprotein (MNP) by synthesizing a sequence that maximized the representation of 9-mer epitopes from 7422 NP sequences across human, swine, and avian IAVs.

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Background: subspecies (MAP) causes a chronic and progressive granulomatous enteritis and economic losses in dairy cattle in subclinical stages. Subclinical infection in cattle can be detected using serum MAP antibody enzyme-linked immunosorbent assay (ELISA) and fecal polymerase chain reaction (PCR) tests.

Objectives: To investigate the differences in blood parameters, according to the detection of MAP using serum antibody ELISA and fecal PCR tests.

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Although SARS-CoV-2 evolution seeds a continuous stream of antibody-evasive viral variants, COVID-19 mRNA vaccines provide robust protection against severe disease and hospitalization. Here, we asked whether mRNA vaccine-induced memory T cells limit lung SARS-CoV-2 replication and severe disease. We show that mice and humans receiving booster BioNTech mRNA vaccine developed potent CD8 T cell responses and showed similar kinetics of expansion and contraction of granzyme B/perforin-expressing effector CD8 T cells.

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Article Synopsis
  • Mycobacterium avium subspecies paratuberculosis (MAP) causes Johne's disease in ruminants, leading to significant economic losses in the bovine industry, and there are still unanswered questions regarding its diagnosis and pathogenesis.
  • In a study using a murine model, mice infected with MAP via intraperitoneal (IP) injection exhibited more severe responses in the spleen and liver compared to those infected orally, showing increased organ size and significant histopathological changes at 12 weeks post-infection.
  • The research also highlighted an immune response shift from Th1 to Th17 during early MAP infection, with notable increases in proinflammatory cytokines and metabolism alterations, including reduced glucose availability and cholesterol production, which contributes
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Although Mycobacterium avium subsp. (MAP) has threatened public health and the livestock industry, the current diagnostic tools (e.g.

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Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease, a chronic debilitating disease in ruminants. To control this disease, it is crucial to understand immune evasion and the mechanism of persistence by analyzing the early phase interplays of the intracellular pathogens and their hosts.

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Mycobacterium avium-intracellulare complex (MAC) is one of the most prevalent pathogenic nontuberculous mycobacteria that cause chronic pulmonary disease. The prevalence of MAC infection has been rising globally in a wide range of hosts, including companion animals. MAC infection has been reported in dogs; however, little is known about interaction between MAC and dogs, especially in immune response.

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Paratuberculosis (PTB) is a chronic contagious granulomatous enteritis of wild and domestic ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). PTB causes considerable economic losses to the dairy industry through decreased milk production and premature culling.

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Mycobacterium avium subsp. paratuberculosis (MAP) is the causative agent of Johne's disease (JD), and it causes diarrhea and weakness in cattle. During a long subclinical stage, infected animals without clinical signs shed pathogens through feces.

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Mycobacterium avium subsp. paratuberculosis (MAP) is a causative agent of Johne's disease, which is a chronic and debilitating disease in ruminants. MAP is also considered to be a possible cause of Crohn's disease in humans.

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Johne's disease (JD) is a chronic granulomatous enteritis of ruminants caused by subsp. (MAP), which induces persistent diarrhea and cachexia. JD causes huge economic losses to the dairy industry due to reduced milk production and premature culling.

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Article Synopsis
  • Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease in ruminants, making its genetic diversity crucial for understanding how it spreads and how to control it.
  • The study analyzed 40 MAP genomes, including new isolates, to identify new genomic structures and categorize MAP into two main types (C- and S-type), also noting a distinct B-type.
  • A new real-time PCR technique was developed based on the pangenome analysis to differentiate between S-, B-, and C-type strains, highlighting how genetic differences explain variations in the traits of MAP.
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, an opportunistic intracellular pathogen, is a member of the non-tuberculous mycobacteria species. causes respiratory disease in immunosuppressed individuals and a wide range of animals, including companion dogs and cats. In particular, the number of infected companion dogs has increased, although the underlying mechanism of pathogenesis in dogs has not been studied.

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Johne's disease (JD) caused by Mycobacterium avium subsp. paratuberculosis (MAP) is a chronic, wasting infectious disease in ruminants that causes enormous economic losses to the dairy and beef cattle industries. Understanding the mechanism of persistency of MAP is key to produce novel ideas for the development of new diagnostic methods or prevention techniques.

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Non-tuberculous mycobacteria (NTM) are ubiquitous microorganisms that have the potential to cause disease in both humans and animals. Recently, NTM infections have rapidly increased in South Korea, especially in urbanized areas. However, the distribution of species and the antibiotic resistance profile of NTM in environmental sources have not yet been investigated.

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Infection with Brucella abortus causes contagious zoonosis, brucellosis, and leads to abortion in animals and chronic illness in humans. Chitosan nanoparticles (CNs), biocompatible and nontoxic polymers, acts as a mucosal adjuvant. In our previous study, B.

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The aim of this study was to investigate the induction of mucosal immune responses by an important Brucella abortus antigen, malate dehydrogenase (Mdh), loaded in mucoadhesive chitosan nanoparticles (CNs) and immunized intranasally in a BALB/c mouse model. The production of cytokines was investigated in human leukemic monocyte cells (THP-1 cells) after stimulation with the nanoparticles. Mdh-loaded CNs (CNs-Mdh) induced higher interleukin (IL)-6 production than unloaded antigens and TF loaded CNs (CNs-TF).

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The aim of this study was to describe the genetic diversity of subsp. (MAP) obtained from individual cows in Korea. Twelve MAP-positive fecal DNA samples and 19 MAP isolates were obtained from 10 cattle herds located in 5 provinces in Korea.

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Johne's disease is a chronic wasting disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP), resulting in inflammation of intestines and persistent diarrhea. The initial host response against MAP infections is mainly regulated by the Th1 response, which is characterized by the production of IFN-γ.

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Article Synopsis
  • Mycobacterium avium subsp. paratuberculosis (MAP) causes Johne's disease, a chronic illness in ruminants characterized by enteritis and diarrhea.
  • The study found that non-MAP mycobacteria, specifically M. virginiense and M. nonchromogenicum, tested positive for ISMap02 targeting PCR, indicating a potential cross-reactivity issue in diagnostics.
  • The research highlighted that ISMap02 shares similarities with other insertion sequences, suggesting the need to reassess its specificity and reliability as a diagnostic tool.
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This study investigated 247 Escherichia coli isolates collected from four cattle farms to characterize aminoglycoside-modifying enzyme (AME) genes, their plasmid replicons and transferability. Out of 247 isolates a high number of isolates (total 202; 81.78%) were found to be resistant to various antibiotics by disc diffusion.

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Bovine paratuberculosis (PTB) is a chronic enteric inflammatory disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP) that causes large economic losses in the dairy industry. Spread of PTB is mainly provoked by a long subclinical stage during which MAP is shed into the environment with feces; accordingly, detection of subclinical animals is very important to its control.

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Paratuberculosis (PTB) is caused by subsp. (MAP) and is one of the most widespread and economically important diseases in cattle. After birth, calves are raised with natural breast feeding without separation from their mothers in most Korean native cattle (Hanwoo breed) farms.

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Johne's disease or paratuberculosis is a chronic debilitating disease in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). The disease causes significant economic losses in livestock industries worldwide.

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