Project description:Microarray comparative genome hybridization (mCGH) data was collected from one Neisseria cinerea, two Neisseria lactamica, two Neisseria gonorrhoeae, and 48 Neisseria meningitidis isolates. For N. meningitidis, these isolates are from diverse clonal complexes, invasive and carriage strains, and all major serogroups. The microarray platform represented N. meningitidis strains MC58, Z2491, and FAM18 and N. gonorrhoeae FA1090.
Project description:Species of the Neisseria genus harbor close relationships with their mamallian hosts, including humans. The outcome of these interactions can result in commensalism, asymptomatic carriage, or acute inflammatory responses. Little is known of the mechanisms Neisseria use to maintain and shape their host niche in the context of asymptomatic infection or long term commensal colonization and persistence. To identify novel host interaction factors contributing to host persistence, a Tn5 transposon library was created in Neisseria musculi, and inoculated into a permissive strain of laboratory mice (CAST/EiJ). At various time points post inoculation, transposon mutants were recovered from fecal and oral samples, and analyzed to identifiy mutants incapable of maintaining a host niche at either site.
Project description:Secondary bacterial pneumonia following influenza infection is a significant cause of mortality worldwide. Upper respiratory tract pneumococcal carriage is important as both determinants of disease and population transmission. The immunological mechanisms that contain pneumococcal carriage are well-studied in mice but remain unclear in humans. Loss of this control of carriage following influenza infection is associated with secondary bacterial pneumonia during seasonal and pandemic outbreaks. We used a human type 6B pneumococcal challenge model to show that carriage acquisition induces early degranulation of resident neutrophils and recruitment of monocytes to the nose. Monocyte function associated with clearance of pneumococcal carriage. Prior nasal infection with live attenuated influenza virus induced inflammation, impaired innate function and altered genome-wide nasal gene responses to pneumococcal carriage. Levels of the cytokine IP-10 promoted by viral infection at the time of pneumococcal encounter was positively associated with bacterial density. These findings provide novel insights in nasal immunity to pneumococcus and viral-bacterial interactions during co-infection.
