Die Rolle verschiedener Virulenzfaktoren von Streptococcus pneumoniae bei der Meningitis: Untersuchung am Mausmodell
The role of virulence factors of Streptococcus pneumoniae in meningitis: mouse model study
von Tammo Helmut Kunst
Datum der mündl. Prüfung:2015-09-15
Erschienen:2015-09-11
Betreuer:Prof. Dr. Roland Nau
Gutachter:Prof. Dr. Roland Nau
Gutachter:PD Dr. Fred Lühder
Dateien
Name:Virulenzfaktoren Pneumokokkenmeningitis.pdf
Size:1.83Mb
Format:PDF
Zusammenfassung
Englisch
The present study examines virulence factors of S. pneumoniae in mouse model. After intracerebral injection virulence factors of D39-wild-type S. pneumoniae were compared with isogenetic derivates. These infection strains showed deficiency in one virulence factor (Ply, Hyl, NanA or NanB). Target parameters were clinic (vigilance, motor ability, loss of weight), bacteriology (in blood, cerebellum, spleen) as well as the morphological image (meningeal inflammatory score, neuronal damage defect). Ply-/- and D39-infectiongroup were compared in overall survival. The result showed statistically significant differences in clinical apperance in the ply-/- group after 32h/36h of infection as well as in rope-test after 36h post inoculation. The evaluation in bacteriology demonstrated statistically significant lower titer in mouse blood which was infectet with ply-/- S. strains. The morphological image reveals minor meningeal inflammatory reactions as in the comparison groups. These results could also be reproduced in the overall survival. The minor clinical symptoms, a lower bacterial blood count and the reduced meningeal inflammatory reaction suggest pneumolysin as an important virulence factor in S. pneumoniae and consequently might have a high potential as possible target substance for the design of vaccines. It should be object of further clinical research.
Keywords: Streptococcus pneumoniae; virulence factors; mouse model; bacterial titer; meningeal inflammatory score