Project description:RSV, a leading cause of severe respiratory illnesses in vulnerable populations, lacks effective, affordable treatments for pediatric use. The potential of traditional Chinese medicine for relieving viral symptoms prompted this investigation into Xuanfei Formula (XFF) as an anti-RSV agent. This study employed H&E staining, cytokine profiling, and RSV titer quantification in BALB/c mice to evaluate the impact of XFF on RSV infection. Strikingly, immediate post-treatment observation showed a precipitous drop in both serum pro-inflammatory cytokine levels and pulmonary RSV-N gene copies in comparison to infected controls, suggesting XFF’s direct anti-RSV action. Transcriptome analyses were used to pinpointed the underlying mechanism behind formula’s immune-independent anti-RSV, a leading cause of severe respiratory illnesses in vulnerable populations, lacks effective, affordable treatments for pediatric use. The potential of traditional Chinese medicine for relieving viral symptoms prompted this investigation into Xuanfei Formula (XFF) as an anti-RSV agent. This study employed H&E staining, cytokine profiling, and RSV titer quantification in BALB/c mice to evaluate the impact of XFF on RSV infection. Strikingly, immediate post-treatment observation showed a precipitous drop in both serum pro-inflammatory cytokine levels and pulmonary RSV-N gene copies in comparison to infected controls, suggesting XFF’s direct anti-RSV action. Transcriptome analyses were used to pinpointed the underlying mechanism behind formula’s immune-independent anti-RSV effects during infection.
Project description:To investigate how human airway epithelial cells respond to Influenza or RSV infection, we harvested airway epithelial cells from the mainstream bronchi of human donors and cultured them as previously described (Pickles et al,1998) in a polarized system that resembles the in vivo mucociliary pseudostratified epithelium. Quadruplicate hAEC cultures were infected with 2X105 PFUs Influenza A (Udorn) or with 1x106 PFUs RSV for 2h or mock inoculated and harvested 24h after Influenza infection and 48h after RSV infection. Quadruplicate polarized airway epithelial cell cultures were mock treated or infected with 2x10^5 PFUs of Influenza A (Udorn) for 2h or infected with 1x10^6 PFUs RSV and harvested 24 h post infection for Influenza or 48h post infection for RSV. Total RNA was harvested and gene expression was studied using Genespring GX v7.3.1.
Project description:To investigate how human airway epithelial cells respond to Influenza or RSV infection, we harvested airway epithelial cells from the mainstream bronchi of human donors and cultured them as previously described (Pickles et al,1998) in a polarized system that resembles the in vivo mucociliary pseudostratified epithelium. Quadruplicate hAEC cultures were infected with 2X105 PFUs Influenza A (Udorn) or with 1x106 PFUs RSV for 2h or mock inoculated and harvested 24h after Influenza infection and 48h after RSV infection. Quadruplicate polarized airway epithelial cell cultures were infected with 2x10^5 PFUs of Influenza A (Udorn) for 2h or infected with 1x10^6 PFUs RSV and harvested 24 h post infection for Influenza or 48h post infection for RSV.Duplicate cultures were used as controls for each condition (Two cultures were mock treated mor 2h and harvested after 24h for the Influenza infection and 2 cultures were mock treated for 2h and harvested after 48 hours for the RSV infection.Total RNA was harvested and gene expression was studied using Genespring GX v7.3.1.
Project description:To study the transcriptional profile of patients with acute RSV or Influenza infection,children of median age 2.4 months (range 1.5-8.6) hospitalized with acute RSV and influenza virus infection were offered study enrollment after microbiologic confirmation of the diagnosis. Blood samples were collected from them within 42-72 hours of hospitalization. We excluded children with suspected or proven polymicrobial infections, with underlying chronic medical conditions (i.e congenital heart disease, renal insufficiency), with immunodeficiency, or those who received systemic steroids or other immunomodulatory therapies. The RSV cohort consisted of 51 patients with median age of 2 months (range 1.5-3.9) and the influenza cohort had 28 patients with median age of 5.5 months (range 1.4-21). Control samples were obtained from healthy children undergoing elective surgical procedures or at outpatient clinic visits. To exclude viral co-infections we performed nasopharyngeal viral cultures of all subjects. We recruited 10 control patients for the RSV cohort with median age of 6.7 months (range 5-10), and 12 control patients for the influenza cohort with median age of18.5 months (range 10.5-26). We used microarrays to obtain the transcriptional profile of PBMCs from patients with acute RSV or Influenza infection and compared these signatures with the transcriptional profile of primary airway epithelial cells infected with RSV or Influenza.
Project description:Rationale: Respiratory syncytial virus (RSV) and Streptococcus pneumoniae are major respiratory pathogens. Co-infection with RSV and S. pneumoniae is associated with severe and often fatal pneumonia but the molecular basis for this remains unclear. Objectives: To determine if interaction between RSV and pneumococci enhances pneumococcal virulence. Methods: We used confocal microscopy and western blot to identify the receptors involved in direct binding of RSV and pneumococci, the effects of which were studied in both in vivo and in vitro models of infection. Human ciliated respiratory epithelial cell cultures were infected with RSV for 72h and then challenged with pneumococci. Pneumococci were collected after 2h exposure and changes in gene expression determined using qRT-PCR. Results: Following incubation with RSV or purified G protein, pneumococci demonstrated a significant increase in the inflammatory response and bacterial adherence to human ciliated epithelial cultures and markedly increased virulence in a pneumonia model in mice. This was associated with extensive changes in the pneumococcal transcriptome and significant upregulation in the expression of key pneumococcal virulence genes, including the gene for the pneumococcal toxin, pneumolysin. We show that mechanistically this is due to RSV G glycoprotein binding penicillin binding protein 1a. Conclusion: The direct interaction between a respiratory virus protein and the pneumococcus resulting in increased bacterial virulence and worsening disease outcome is a new paradigm in respiratory infection. Comparison of the Streptococcus pneumoniae D39 RSV treated compared to BSA Treated in BEBM medium One condition design comparision of two strains including a dye swap
Project description:To investigate how human airway epithelial cells respond to Influenza or RSV infection, we harvested airway epithelial cells from the mainstream bronchi of human donors and cultured them as previously described (Pickles et al,1998) in a polarized system that resembles the in vivo mucociliary pseudostratified epithelium. Quadruplicate hAEC cultures were infected with 2X105 PFUs Influenza A (Udorn) or with 1x106 PFUs RSV for 2h or mock inoculated and harvested 24h after Influenza infection and 48h after RSV infection.
Project description:To investigate how human airway epithelial cells respond to Influenza or RSV infection, we harvested airway epithelial cells from the mainstream bronchi of human donors and cultured them as previously described (Pickles et al,1998) in a polarized system that resembles the in vivo mucociliary pseudostratified epithelium. Quadruplicate hAEC cultures were infected with 2X105 PFUs Influenza A (Udorn) or with 1x106 PFUs RSV for 2h or mock inoculated and harvested 24h after Influenza infection and 48h after RSV infection.
Project description:Viral infection often triggers eukaryotic initiator factor 2α (eIF2α) phosphorylation, leading to global 5’-cap-dependent translation inhibition. RSV encodes messenger RNAs (mRNAs) mimicking 5’-cap structures of host mRNAs and thus inhibition of cap-dependent translation initiation would likely also reduce viral translation. We confirmed that RSV limits widespread translation initiation inhibition and unexpectedly found that the fraction of ribosomes within polysomes increases during infection, indicating higher ribosome loading on mRNAs during infection. We found that AU-rich host transcripts that are less efficiently translated under normal conditions become more efficient at recruiting ribosomes, similar to RSV transcripts. Viral transcripts are transcribed in cytoplasmic inclusion bodies, where the viral AU-rich binding protein M2-1 has been shown to bind viral transcripts and shuttle them into the cytoplasm. We further demonstrated that M2-1 is found on polysomes, and that M2-1 might deliver host AU-rich transcripts for translation.
Project description:Rationale: Respiratory syncytial virus (RSV) and Streptococcus pneumoniae are major respiratory pathogens. Co-infection with RSV and S. pneumoniae is associated with severe and often fatal pneumonia but the molecular basis for this remains unclear. Objectives: To determine if interaction between RSV and pneumococci enhances pneumococcal virulence. Methods: We used confocal microscopy and western blot to identify the receptors involved in direct binding of RSV and pneumococci, the effects of which were studied in both in vivo and in vitro models of infection. Human ciliated respiratory epithelial cell cultures were infected with RSV for 72h and then challenged with pneumococci. Pneumococci were collected after 2h exposure and changes in gene expression determined using qRT-PCR. Results: Following incubation with RSV or purified G protein, pneumococci demonstrated a significant increase in the inflammatory response and bacterial adherence to human ciliated epithelial cultures and markedly increased virulence in a pneumonia model in mice. This was associated with extensive changes in the pneumococcal transcriptome and significant upregulation in the expression of key pneumococcal virulence genes, including the gene for the pneumococcal toxin, pneumolysin. We show that mechanistically this is due to RSV G glycoprotein binding penicillin binding protein 1a. Conclusion: The direct interaction between a respiratory virus protein and the pneumococcus resulting in increased bacterial virulence and worsening disease outcome is a new paradigm in respiratory infection.
Project description:We studied RSV infection in an appropriate in vitro model of respiratory epithelium, a pseudostratified and fully differentiated mucociliary epithelium of normal human bronchial epithelial (NHBE) cells. RSV infection increased actin cytoskeleton without compromising adherent-, tight-, and tricellular-junctions as well as ciliary functions and epithelial tissue barrier integrity. This increased cytoskeleton depends on actin polymerization and the induction of proinflammatory cytokines and chemokines. Thus, we observed a novel signature “increased cytoskeleton” termed “cytoskeletal inflammation” in RSV-infected respiratory epithelium that presumably lacks classical antigen presenting cells, such as resident dendritic cells and macrophages. Our results suggest that RSV-induced cytoskeletal inflammation is a noncanonical earliest host response to the pathogen and contributes to airway inflammation.