OBJECTIVES: To investigate the effect of interferon-λ1 (IFN-λ1) on glucocorticoid (GC) resistance in human bronchial epithelial cells (HBECs) stimulated by respiratory syncytial virus (RSV). METHODS: HBECs were divided into five groups: control, dexamethasone, IFN-λ1, RSV, and RSV+IFN-λ1. CCK-8 assay was used to measure the effect of different concentrations of IFN-λ1 on the viability of HBECs, and the sensitivity of HBECs to dexamethasone was measured in each group. Quantitative real-time PCR was used to measure the mRNA expression levels of p38 mitogen-activated protein kinase (p38 MAPK), glucocorticoid receptor (GR), and MAPK phosphatase-1 (MKP-1). Western blot was used to measure the protein expression level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic ratio of GR was calculated. RESULTS: At 24 and 72 hours, the proliferation activity of HBECs increased with the increase in IFN-λ1 concentration in a dose- and time-dependent manner (P˂0.05). Compared with the RSV group, the RSV+IFN-λ1 group had significant reductions in the half-maximal inhibitory concentration of dexamethasone and the mRNA expression level of p38 MAPK (P<0.05), as well as significant increases in the mRNA expression levels of GR and MKP-1, the level of GR in cell nucleus and cytoplasm, and the nuclear/cytoplasmic GR ratio (P<0.05). CONCLUSIONS IFN-λ1 can inhibit the p38 MAPK pathway by upregulating MKP-1, promote the nuclear translocation of GR, and thus ameliorate GC resistance in HBECs.
Humans ; p38 Mitogen-Activated Protein Kinases/genetics* ; Glucocorticoids/pharmacology* ; Receptors, Glucocorticoid/analysis* ; Dual Specificity Phosphatase 1/physiology* ; Dexamethasone/pharmacology* ; Drug Resistance/drug effects* ; Respiratory Syncytial Viruses ; Interferons/pharmacology* ; MAP Kinase Signaling System/drug effects* ; Epithelial Cells/drug effects* ; Signal Transduction/drug effects* ; Cells, Cultured

Seven novel acylphloroglucinol-sesquiterpenoid adducts, designated as dryatraols J-P (1-7), were isolated from the rhizomes of Dryopteris atrata (Wall. ex Kunze) Ching. The structures, including absolute configurations, were elucidated using comprehensive spectroscopic data, calculated ¹³C Nuclear Magnetic Resonance-Diastereotopic Probability Assignment Plus (¹³C NMR-DP4+) probability analysis, and ECD calculations. These structures represent a rare subclass of carbon skeleton of acylphloroglucinol-sesquiterpenoid adducts with a furan ring connecting the acylphloroglucinol and sesquiterpenoid moieties. Notably, compounds 1-6 are the first reported examples of acylphloroglucinol-sesquiterpenoid adducts with dimeric acylphloroglucinol incorporated into the aristolane- or rulepidanol-type sesquiterpene, while compound 7 features a hydroxylated monomeric acylphloroglucinol motif. A preliminary evaluation of their antiviral activities revealed that compounds 1-6 exhibited more potent activities against respiratory syncytial virus (RSV) with IC₅₀ values ranging from 0.75 to 3.12 μmol·L^-1 compared to the positive control (ribavirin).
Antiviral Agents/isolation & purification* ; Phloroglucinol/isolation & purification* ; Sesquiterpenes/isolation & purification* ; Molecular Structure ; Dryopteris/chemistry* ; Respiratory Syncytial Viruses/drug effects* ; Humans ; Rhizome/chemistry* ; Drugs, Chinese Herbal/pharmacology*

Peganum harmala L. (P. harmala) is a significant economic and medicinal plant. The seeds of P. harmala have been extensively utilized in traditional Chinese medicine, Uighur medicine, and Mongolian medicine, as documented in the Drug Standard of the Ministry of Health of China. Twelve novel tryptamine-derived alkaloids (1-12) and eight known compounds (13-20) were isolated from P. harmala seeds. Compounds 1 and 2 represent the first reported instances of tryptamine-derived heteromers, comprising tryptamine and aniline fragments with previously undocumented C-3-N-1' linkage and C-3-C-4' connection, respectively. Compounds 3-5 were identified as indole-quinazoline heteromers, exhibiting a novel C-3 and NH-1' linkage between indole and quinazoline-derived fragments. Compound 6 demonstrates the dimerization pattern of C-C linked tryptamine-quinazoline dimer. Compound 8 represents a tryptamine-derived heterodimer with a distinctive carbon skeleton, featuring an unusual spiro-tricyclic ring (7) and conventional bicyclic tryptamine. Compounds 9-11 constitute novel 6/5/5/5 spiro-tetracyclic tryptamine-derived alkaloids presenting a unique ring system of tryptamine-spiro-pyrrolizine. Compounds 1-3 and 6-11 were identified as racemates. Compounds 2, 7, 9, 10, and 12 were confirmed via X-ray crystallographic analysis. All isolated compounds (1-20) exhibited varying degrees of antiviral efficacy against respiratory syncytial virus (RSV). Notably, the anti-RSV activity of compound 12 (IC₅₀ 5.01 ± 0.14 μmol·L^-1) surpassed that of the positive control (ribavirin, IC₅₀ 6.23 ± 0.95 μmol·L^-1), as validated through plaque reduction and immunofluorescence assays. The identification of anti-RSV compounds from P. harmala seeds may enhance the development and application of this plant in antiviral therapeutic products.
Antiviral Agents/isolation & purification* ; Tryptamines/isolation & purification* ; Peganum/chemistry* ; Seeds/chemistry* ; Alkaloids/isolation & purification* ; Molecular Structure ; Humans ; Respiratory Syncytial Viruses/drug effects* ; Plant Extracts/pharmacology* ; Drugs, Chinese Herbal/pharmacology*

Respiratory syncytial virus (RSV) is an enveloped, negative-sense, single-stranded RNA virus of the Orthopneumovirus  genus of the Pneumoviridae family in the order Mononegavirales. RSV can cause acute upper and lower respiratory tract infections, sometimes with extrapulmonary complications. The disease burden of RSV infection is enormous, mainly affecting infants and older adults aged 75 years or above. Currently, treatment options for RSV are largely supportive. Prevention strategies remain a critical focus, with efforts centered on vaccine development and the use of prophylactic monoclonal antibodies. To date, three RSV vaccines have been approved for active immunization among individuals aged 60 years and above. For children who are not eligible for these vaccines, passive immunization is recommended. A newly approved prophylactic monoclonal antibody, Nirsevimab, which offers enhanced neutralizing activity and an extended half-life, provides exceptional protection for high-risk infants and young children. This review provides a comprehensive and detailed exploration of RSV's virology, immunology, pathogenesis, epidemiology, clinical manifestations, treatment options, and prevention strategies.
Humans ; Respiratory Syncytial Virus Infections/prevention & control* ; Respiratory Syncytial Viruses/pathogenicity* ; Respiratory Syncytial Virus, Human/pathogenicity* ; Antiviral Agents/therapeutic use*

Lower respiratory tract infection (LRTI) induced by respiratory syncytial virus (RSV) is an important cause of hospitalization for infants. Compared with adults, infants are more likely to cause serious respiratory diseases after RSV infection due to the specific immature airway structure and immune system. The balance of immune resistance and immune tolerance of the host is critical to effective virus clearance and disease control. This paper reviews the relationship between RSV infection and respiratory diseases in infancy, the influence factors of the high pathogenicity of RSV infection in early life, as well as the research progress of anti-RSV therapy, and expands the specific molecular events regulating immune resistance and immune tolerance. We expect to present new ideas for the prevention and treatment of RSV-related respiratory diseases in clinical practice.
Humans ; Infant ; Respiration Disorders ; Respiratory Syncytial Virus Infections ; Respiratory Syncytial Viruses ; Respiratory Tract Infections

BACKGROUND: This study investigated the effect of fine dust concentrations in the air on the incidence of viral respiratory infections in the Republic of Korea.METHODS: A time series analysis using R statistics was performed to determine the relationship between weekly concentrations of fine dust in the air and the incidences of acute respiratory tract infections caused by the respiratory syncytial virus (RSV), adenovirus (HAdV), rhinovirus (HRV), human metapneumovirus (HMPV), human coronavirus (HCoV), human bocavirus (HBoV), human parainfluenza virus (HPIV), and influenza virus (IFV), from the beginning of 2016 to the end of 2017. Correlations between various meteorological factors and the amount of fine dust were analyzed using the Spearman's rank correlation coefficient. To analyze the relationship between viral infections and fine dust, a quasi-poisson analysis was performed.RESULTS: The incidence of the HAdV was proportional to fine dust and air temperature. The IFV was proportional to fine dust and relative humidity and was inversely proportional to temperature. The HMPV was proportional to fine dust, wind speed, and inversely proportional to relative humidity. The HCoV was proportional to micro dust, relative humidity, and inversely proportional to temperature. Both the HBoV and HPIV were directly proportional to fine dust, temperature, wind speed, and inversely proportional to relative humidity. The RSV was inversely proportional to fine dust, temperature, wind speed. A lag effect was observed for the influenza virus, in that its incidence increased 2–3 weeks later on the cumulative lag model.CONCLUSION: As the weekly average concentration of fine dust increases, the incidence of HAdV, HMPV, HCoV, HBoV, HPIV, and influenza increase.
Adenoviridae ; Air Pollution ; Coronavirus ; Dust ; Human bocavirus ; Humans ; Humidity ; Incidence ; Influenza, Human ; Metapneumovirus ; Meteorological Concepts ; Orthomyxoviridae ; Paramyxoviridae Infections ; Particulate Matter ; Republic of Korea ; Respiration Disorders ; Respiratory Syncytial Viruses ; Respiratory Tract Infections ; Rhinovirus ; Wind

PURPOSE: Respiratory syncytial virus (RSV) can cause serious respiratory illnesses such as pneumonia, asthma, and bronchiolitis in infants and elderly or immunocompromised individuals. An RSV vaccine has yet to be developed; only prophylactic anti-RSV antibody is commercially available. So, we investigated whether our vaccine candidate is able to induce type 1 CD4+ T helper (Th1), CD8+ T-cell responses, and protective immunity without vaccine-enhanced disease (VED) against RSV. MATERIALS AND METHODS: We used RSV G protein fragment (Gcf A) with recombinant baculovirus capable of expressing the RSV M2 protein (Bac M2) as a vaccine candidate, and injected this vaccine (Gcf A/Bac M2) intramuscularly, and challenged with RSV intranasally into mice. Enzyme-linked immunosorbent assay, flow cytometry, plaque assay, and weight measurement were performed to confirm humoral immunity, cellular immunity, and protective immunity. RESULTS: The Gcf A/Bac M2 formulation induced a stronger IgG response to Gcf A than Gcf A inoculation alone, and the ratio of IgG1/IgG2a indicated that the responses shifted predominantly to Th1. In addition, both RSV G-specific Th1 responses and RSV M2-specific CD8+ T-cell responses were induced, and G protein-associated eosinophilic infiltration was suppressed compared to the control group. Moreover, the Gcf A/Bac M2 group showed effective protection after an RSV challenge. CONCLUSION: Bac M2 could serve as a vaccine with intrinsic adjuvant activity, and the Gcf A/Bac M2 shows promise as a vaccine candidate for inducing protective immunity without inciting VED.
Aged ; Animals ; Asthma ; Baculoviridae* ; Bronchiolitis ; Enzyme-Linked Immunosorbent Assay ; Eosinophils ; Flow Cytometry ; GTP-Binding Proteins* ; Humans ; Immunity, Cellular ; Immunity, Humoral ; Immunoglobulin G ; Infant ; Mice ; Pneumonia ; Respiratory Syncytial Viruses* ; T-Lymphocytes

PURPOSE: Multiple virus infections may affect clinical severity. We investigated the effect of coinfection of respiratory syncytial virus (RSV) and influenza virus with other respiratory viruses on clinical severity. METHODS: Data from 634 samples of a single tertiary hospital between September 2014 and April 2015 were analyzed for clinical characteristics (fever duration and O2 need, steroid use, and ICU care) between single infection and coinfection of RSV (n=290) and influenza virus (n=74) with 16 common respiratory viruses from hospitalized children. RESULTS: The RSV coinfection group (n=109) (3.1±2.7 days) showed significantly longer fever duration than the RSV single infection group (n=181) (2.6±2.6 days) (P=0.04), while there was no difference in O2 need, steroid use or ICU care in the 2 groups. The influenza coinfection group (n=38) showed significantly higher O2 need than the influenza single infection group (n=36) (21.1% vs. 5.6%, P=0.05), while there was no difference in fever duration between the 2 groups. CONCLUSION: The results indicate that RSV and Influenza coinfections can increase clinical severity and that the severity may be influenced by the nature of coinfecting viruses.
Child ; Child, Hospitalized ; Coinfection ; Dyspnea ; Fever ; Humans ; Influenza, Human ; Orthomyxoviridae ; Respiratory Syncytial Viruses ; Tertiary Care Centers

PURPOSE: Croup is known to have epidemics in seasonal and biennial trends, and to be strongly associated with epidemics of parainfluenza virus. However, seasonal and annual epidemics of croup have not been clearly reported in Korea. This study aimed to examine the seasonal/annual patterns and etiologies of childhood croup in Korea during a consecutive 6-year period. METHODS: Pediatric croup data were collected from 23 centers in Korea from 1 January 2010 to 31 December 2015. Electronic medical records, including multiplex reverse transcription polymerase chain reaction (RT-PCR) results, demographics and clinical information were cross-sectionally reviewed and analyzed. RESULTS: Overall, 2,598 childhood croup patients requiring hospitalization were identified during the study period. Among them, a total of 927 who underwent RT-PCR were included in the analysis. Males (61.5%) predominated, and most (63.0%) of them were younger than 2 years of age (median, 19 months; interquartile range, 11–31 months). Peak hospitalization occurred in 2010 and 2012 in even-numbered years, and parainfluenza virus (PIV, 39.7%) was the most common cause of childhood croup requiring hospitalization, followed by respiratory syncytial virus (14.9%), human rhinovirus (12.5%), Mycoplasma pneumonaie (10.6%), and human coronavirus (7.3%). CONCLUSION: It is concluded that croup hospitalization has a biennial pattern in even-numbered years. PIV may be the most common cause of childhood croup; however, croup epidemics could be attributed to other viruses.
Child ; Coronavirus ; Croup ; Demography ; Electronic Health Records ; Hospitalization ; Humans ; Korea ; Male ; Mycoplasma ; Paramyxoviridae Infections ; Polymerase Chain Reaction ; Respiratory Syncytial Viruses ; Retrospective Studies ; Reverse Transcription ; Rhinovirus ; Seasons

Formalin-inactivated respiratory syncytial virus (RSV) vaccination causes vaccine-enhanced disease (VED) after RSV infection. It is considered that vaccine platforms enabling endogenous synthesis of RSV immunogens would induce favorable immune responses than non-replicating subunit vaccines in avoiding VED. Here, we investigated the immunogenicity, protection, and disease in mice after vaccination with RSV fusion protein (F) encoding plasmid DNA (F-DNA) or virus-like particles presenting RSV F (F-VLP). F-DNA vaccination induced CD8 T cells and RSV neutralizing Abs, whereas F-VLP elicited higher levels of IgG2a isotype and neutralizing Abs, and germinal center B cells, contributing to protection by controlling lung viral loads after RSV challenge. However, mice that were immunized with F-DNA displayed weight loss and pulmonary histopathology, and induced F specific CD8 T cell responses and recruitment of monocytes and plasmacytoid dendritic cells into the lungs. These innate immune parameters, RSV disease, and pulmonary histopathology were lower in mice that were immunized with F-VLP after challenge. This study provides important insight into developing effective and safe RSV vaccines.
Animals ; B-Lymphocytes ; Dendritic Cells ; DNA ; Germinal Center ; Immunoglobulin G ; Lung ; Mice ; Monocytes ; Plasmids ; Respiratory Syncytial Virus Vaccines ; Respiratory Syncytial Viruses ; T-Lymphocytes ; Vaccination ; Vaccines, Subunit ; Viral Load ; Weight Loss