• Pediatric Infection and Vaccine
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• v.6 no.1
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• pp.131-135
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• 1999

Respiratory Syncytial Virus(RSV) causes acute respiratory tract infections in young infancy such as bronchiolitis, pneumonia. RSV infections are uncommon in the first month of life. Clinical manifestations of neonatal RSV infection are respiratory symptoms, apnea and bacterial sepsis like illness such as lethargy, poor feeding, fever, rash. We report a case of neonatal pneumonia caused by RSV and accompanied by transient apnea and favorable clinical outcome.

• BMB Reports
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• v.44 no.4
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• pp.232-237
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• 2011

Human respiratory syncytial virus (HRSV) is a major cause of upper and lower respiratory tract illness in infants and young children worldwide. Despite its importance as a respiratory pathogen, there is currently no licensed vaccine for prophylaxis of HRSV infection. There are several hurdles complicating the development of a RSV vaccine: 1) incomplete immunity to natural RSV infection leading to frequent re-infection, 2) immature immune system and maternal antibodies of newborn infants who are the primary subject population, and 3) imbalanced Th2-biased immune responses to certain vaccine candidates leading to exacerbated pulmonary disease. After the failure of an initial trial featuring formalin-inactivated virus as a RSV vaccine, more careful and deliberate efforts have been made towards the development of safe and effective RSV vaccines without vaccine-enhanced disease. A wide array of RSV vaccine strategies is being developed, including live-attenuated viruses, protein subunit-based, and vector-based candidates. Though licensed vaccines remain to be developed, our great efforts will lead us to reach the goal of attaining safe and effective RSV vaccines in the near future.

• IMMUNE NETWORK
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• v.12 no.1
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• pp.8-17
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• 2012

Background: Respiratory syncytial virus (RSV) is a major cause of severe lower respiratory tract diseases in infancy and early childhood. Despite its importance as a pathogen, there is no licensed vaccine against RSV yet. The attachment glycoprotein (G) of RSV is a potentially important target for protective antiviral immune responses. Recombinant baculovirus has been recently emerged as a new vaccine vector, since it has intrinsic immunostimulatory properties and good bio-safety profile. Methods: We have constructed a recombinant baculovirus-based RSV vaccine, Bac-RSV/G, displaying G glycoprotein, and evaluated immunogenicity and protective efficacy by intranasal immunization of BALB/c mice with Bac-RSV/G. Results: Bac-RSV/G efficiently provides protective immunity against RSV challenge. Strong serum IgG and mucosal IgA responses were induced by intranasal immunization with Bac-RSV/G. In addition to humoral immunity, G-specific Th17- as well as Th1-type T-cell responses were detected in the lungs of Bac-RSV/G-immune mice upon RSV challenge. Neither lung eosinophilia nor vaccine-induced weight loss was observed upon Bac-RSV/G immunization and subsequent RSV infection. Conclusion: Our data demonstrate that intranasal administration of baculovirus-based Bac-RSV/G vaccine is efficient for the induction of protection against RSV and represents a promising prophylactic vaccination regimen.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.261-268
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• 2012

Respiratory syncytial virus (RSV) and influenza virus are the most significant pathogens causing respiratory tract diseases. Composite vaccines are useful in reducing the number of vaccination and confer protection against multiple infectious agents. In this study, we generated fusion of RSV G protein core fragment (amino acid residues 131 to 230) and influenza HA1 globular head domain (amino acid residues 62 to 284) as a dual vaccine candidate. This fusion protein, Gcf-HA1, was bacterially expressed, purified by metal resin affinity chromatography, and refolded in PBS. BALB/c mice were intranasally immunized with Gcf-HA1 in combination with a mucosal adjuvant, cholera toxin (CT). Both serum IgG and mucosal IgA responses specific to Gcf and HA1 were significantly increased in Gcf-HA1/CT-vaccinated mice. To determine the protective efficacy of Gcf-HA1/CT vaccine, immunized mice were challenged with RSV (A2 strain) or influenza virus (A/PR/8/34). Neither detectable viral replication nor pathology was observed in the lungs of the immune mice. These results demonstrate that immunity induced by intranasal Gcf-HA1/CT immunization confers complete protection against both RSV and homologous influenza virus infection, suggesting our Gcf-HA1 vaccine candidate could be further developed as a dual subunit vaccine against RSV and influenza virus.

• BMB Reports
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• v.47 no.4
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• pp.184-191
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• 2014

Respiratory syncytial virus (RSV) is the leading cause of respiratory infection in infants and young children. Severe clinical manifestation of RSV infection is a bronchiolitis, which is common in infants under six months of age. Recently, RSV has been recognized as an important cause of respiratory infection in older populations with cardiovascular morbidity or immunocompromised patients. However, neither a vaccine nor an effective antiviral therapy is currently available. Moreover, the interaction between the host immune system and the RSV pathogen during an infection is not well understood. The innate immune system recognizes RSV through multiple mechanisms. The first innate immune RSV detectors are the pattern recognition receptors (PRRs), including toll-like receptors (TLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), and nucleotide-biding oligomerization domain (NOD)-like receptors (NLRs). The following is a review of studies associated with various PRRs that are responsible for RSV virion recognition and subsequent induction of the antiviral immune response during RSV infection.

• Clinical and Experimental Pediatrics
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• v.54 no.5
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• pp.197-200
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• 2011

Respiratory syncytial virus (RSV) is a major cause of respiratory infection in children. Most of the pediatric population have RSV infection before the age of 2, and recurrent infections are common even within one season. Chronic lung disease, prematurity, along with congenital heart disease (CHD) are major risk factors in severe lower respiratory infection. In hemo-dynamically significant CHD patients with RSV infection, hospitalization is usually needed and the possibility of treatment in intensive care unit and the use of mechanical ventilator support are known to increase. Therefore the prevention of RSV infection in CHD patients is mandatory. The current standard for RSV prevention is immunoprophylaxis by palivizumab. Immunoprophylaxis is recommended monthly in hemodynamically significant CHD patients, up to 5 months. Motabizumab, a second generation drug and newly developing RSV vaccines are also expected to play a key role in RSV prevention in the future. The prophylaxis of RSV infection in CHD patients is cost-effective in both the medical aspect of the patients as well as the socio-economic aspect. Therefore an effort to promote prevention should be made by not only the family of the patients but also by the government.

• Clinical and Experimental Pediatrics
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• v.54 no.5
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• pp.192-196
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• 2011

Respiratory syncytial virus (RSV) is a main cause of hospitalization for bronchiolitis and pneumonia in infants worldwide. Children with hemodynamically significant congenital heart disease (HS-CHD), as well as premature infants are at high risk for severe RSV diseases. Mortality rates for CHD patients hospitalized with RSV have been reported as about 24 times higher compared with those without RSV infection. Recently with advances in intensive care, mortality rates in CHD patients combined with RSV have decreased below 2%. The requirements of intensive care and mechanical ventilation for CHD patients with RSV infection were still higher than those without RSV infection or with non-CHD children. RSV infection has frequently threatened CHD infants with congestive heart failure, cyanosis, or with pulmonary hypertension. As a progressive RSV pneumonitis in those infants develops, the impairment of oxygen uptake, the breathing workload gradually increases and eventually causes to significant pulmonary hypertension, even after the operation. Preventing RSV infection as much as possible is very important, especially in infants with HS-CHD. A humanized monoclonal antibody, palivizumab, has effective in preventing severe RSV disease in high-risk infants, and progressive advances in supportive care including pulmonary vasodilator have dramatically decreased the mortality (<1%). Depending on the global trend, Korean Health Insurance guidelines have approved the use of palivizumab in children <1 year of age with HS-CHD since 2009. Korean data are collected for RSV prophylaxis in infants with CHD.

• IMMUNE NETWORK
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• v.13 no.5
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• pp.163-167
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• 2013

The dynamics of the virus-host interface in the response to respiratory virus infection is not well-understood; however, it is at this juncture that host immunity to infection evolves. Respiratory viruses have been shown to modulate the host response to gain a replication advantage through a variety of mechanisms. Viruses are parasites and must co-opt host genes for replication, and must interface with host cellular machinery to achieve an optimal balance between viral and cellular gene expression. Host cells have numerous strategies to resist infection, replication and virus spread, and only recently are we beginning to understand the network and pathways affected. The following is a short review article covering some of the studies associated with the Tripp laboratory that have addressed how respiratory syncytial virus (RSV) operates at the virus-host interface to affects immune outcome and disease pathogenesis.

• BMB Reports
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• v.48 no.10
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• pp.565-570
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• 2015

In several reports, the respiratory syncytial virus (RSV) was identified as an oncolytic virus in cancer cells (e.g., lung and prostate cancer). However, the effects of RSV in hepatocellular carcinoma (HCC) cells have not yet been investigated. Here, we observed the inhibitory effects of RSV infection in HCC cell-lines. Cell growth was significantly decreased by RSV infection in BNL-HCC, Hep3B, Huh-7 and SNU-739 cells. After RSV infection, plaque formation and syncytial formation were observed in affected Hep3B and Huh-7 cells. RSV protein-expression was also detected in Hep3B and Huh-7 cells; however, only Huh-7 cells showed apoptosis after RSV infection. Furthermore, inhibition of cell migration by RSV infection was observed in BNL-HCC, Hep3B, Huh-7 and SNU-739 cells. Therefore, further investigation is required to clarify the molecular mechanism of RSV-mediated inhibition of HCC cell growth, and to develop potential RSV oncolytic viro-therapeutics.

• Neonatal Medicine
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• v.25 no.4
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• pp.144-152
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• 2018

Purpose: The aim of this study was to investigate the clinical characteristics of Respiratory syncytial virus (RSV) infection during the neonatal period to provide information that is useful in clinical practice and suggest extension of the palivizumab administration. Methods: Neonates admitted to the National Health Insurance Service Ilsan Hospital neonatal intensive care unit due to respiratory symptoms and for whom multiplex reverse transcription-polymerase chain reaction and multiplex real time-polymerase chain reaction tests were performed between October 2011 and May 2016 were included in this study. Medical records were retrospectively reviewed, and data was collected for 156 neonates. Results: Among the 156 neonates, RSV was detected in 114 (73.1%), non-RSV in 25 (16%), and no virus in 17 (10.9%). The majority were full term infants (92.4%) and peak incidence of RSV infection was in January. Post-natal care center infection was more common in the RSV group (46.6%) than that in the other virus groups (24%, P=0.0243). Clinical symptoms were severe in the RSV group in contrast to that in the non-RSV or others groups. The RSV group frequently needed oxygen therapy (P=0.0001) and the duration of hospital stays were longer (P=0.0001). Conclusion: RSV is a significant cause of respiratory infection in neonates and the severity is higher in contrast to that with other viral causes of infection. Infants in post-natal care centers have a high-risk of developing RSV infections; therefore, palivizumab administration may be considered in this group to prevent hospitalization and reduce the duration of hospital stay.