The recruitment of neutrophils to the infected airway occurs early following respiratory syncytial virus (RSV) infection, and high numbers of activated neutrophils in the airway and blood are associated with the development of severe disease. The aim of this study was to investigate whether trans-epithelial migration is sufficient and necessary for neutrophil activation during RSV infection. Here, we used flow cytometry and novel live-cell fluorescent microscopy to track neutrophil movement during trans-epithelial migration and measure the expression of key activation markers in a human model of RSV infection.
View Article and Find Full Text PDFThe novel coronavirus SARS-CoV2 causes COVID-19, a pandemic threatening millions. As protective immunity does not exist in humans and the virus is capable of escaping innate immune responses, it can proliferate, unhindered, in primarily infected tissues. Subsequent cell death results in the release of virus particles and intracellular components to the extracellular space, which result in immune cell recruitment, the generation of immune complexes and associated damage.
View Article and Find Full Text PDFRespiratory syncytial virus (RSV) is a major cause of pediatric respiratory disease. Large numbers of neutrophils are recruited into the airways of children with severe RSV disease. It is not clear whether or how neutrophils enhance recovery from disease or contribute to its pathology.
View Article and Find Full Text PDFRespiratory syncytial virus (RSV) bronchiolitis is the most common cause of infant hospital admissions, but there is limited understanding of the mechanisms of disease, and no specific antiviral treatment. Using a novel primary transepithelial neutrophil migration model and innovative imaging methods, we show that RSV infection of nasal airway epithelium increased neutrophil transepithelial migration and adhesion to infected epithelial cells, which is associated with epithelial cell damage and reduced ciliary beat frequency, but also with a reduction in infectious viral load.Following migration, RSV infection results in greater neutrophil activation, degranulation and release of neutrophil elastase into the airway surface media compared to neutrophils that migrated across mock-infected nasal epithelial cells.
View Article and Find Full Text PDFStreptococcus pneumoniae is the leading cause of bacterial pneumonia. Although this is a vaccine preventable disease, S. pneumoniae still causes over 1 million deaths per year, mainly in children under the age of five.
View Article and Find Full Text PDFLarge numbers of neutrophils migrate into the lungs of children with severe Respiratory Syncytial Virus (RSV) disease. It is unclear how these cells contribute to viral clearance and recovery from infection or whether they contribute to disease pathology. We have developed a novel in vitro model to study neutrophil migration through airway epithelial cells (AECs), the main cellular target of RSV infection.
View Article and Find Full Text PDFThe pneumococcal serine threonine protein kinase (StkP) acts as a global regulator in the pneumococcus. Bacterial mutants deficient in StkP are less virulent in animal models of infection. The gene for this regulator is located adjacent to the gene for its cognate phosphatase in the pneumococcal genome.
View Article and Find Full Text PDFPrim Health Care Res Dev
March 2016
The formation of a local joint professional network (LJPN) in Northamptonshire has led to a joint Continuing professional development initiative and an audit project to determine the take up of annual health checks by patients with diabetes mellitus with dentists, optometrists, pharmacists as well as the usual check with the General Medical Practice team. The findings showed that a significant number of patients (29-50%) do not access available dental, optometry and pharmacy advice. Better collaboration between the professions has the potential to improve health outcomes in diabetes mellitus and other areas where lifestyle modification reduces adverse health risks.
View Article and Find Full Text PDFStreptococcus agalactiae (group B streptococcus [GBS]) is the leading cause of neonatal sepsis and meningitis. In this study, we determined antibody-mediated deposition of complement C3b/iC3b onto the bacterial cell surface of GBS serotypes Ia, Ib, II, III, and V. This was determined for 520 mother and umbilical cord serum sample pairs obtained at the time of birth from a population on the Thailand-Myanmar border.
View Article and Find Full Text PDFAlterations in whole genome expression profiles following exposure of the pneumococcus (strain 172, serotype 23F) to cigarette smoke condensate (160 μg/mL) for 15 and 60 min have been determined using the TIGR4 DNA microarray chip. Exposure to CSC resulted in the significant (P<0.014-0.
View Article and Find Full Text PDFFlagellar gene expression is temporally regulated in response to the assembly state of the growing flagellum. The key mechanism for enforcing this temporal hierarchy in Salmonella enterica serovar Typhimurium is the sigma(28)-FlgM checkpoint, which couples the expression of the late flagellar (P(class3)) genes to the completion of the hook-basal body. This checkpoint is triggered when FlgM is secreted from the cell.
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