Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia
Thrombocytopenia is a common feature in severe infection and the extent of the thrombocytopenia has been correlated to the clinical prognosis. However the pathophysiology behind this phenomenon is not completely understood. Research in the last decade has shown that thrombocytes possess several anti...
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| Formato: | Otro |
| Lenguaje: | sueco Inglés |
| Publicado: |
2008
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| Acceso en línea: | https://stud.epsilon.slu.se/13004/ |
| _version_ | 1855572170352099328 |
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| author | Dreimanis, Kristoffer |
| author_browse | Dreimanis, Kristoffer |
| author_facet | Dreimanis, Kristoffer |
| author_sort | Dreimanis, Kristoffer |
| collection | Epsilon Archive for Student Projects |
| description | Thrombocytopenia is a common feature in severe infection and the extent of the thrombocytopenia has been correlated to the clinical prognosis. However the pathophysiology behind this phenomenon is not completely understood. Research in the last decade has shown that thrombocytes possess several antimicrobial properties, suggesting that they might play a still unknown role in innate immunity. Moreover platelets are known to sequestrate out into lung tissue in response to stimuli like lipopolysaccharide (LPS) and septicaemia. Streptococcus pneumoniae is a common cause of severe community aquired pneumonia and septicaemia. In this project I show that platelets in vitro are activated by S. pneumoniae and can release antimicrobial peptides in response to thrombin. This occurs independent of interactions with other cells. In vivo, I show that platelet deficiency results in increased bacterial numbers within the lungs in a mouse model of S. pneumoniae pneumonia. Histopathological examination of the lungs indicates that platelets co-localise with the bacteria –and may "trap" them within lung tissue. I conclude that platelets contribute to innate immunity to S. pneumoniae pneumonia identifying a potential therapeutic target for patients with severe infection. |
| format | Otro |
| id | RepoSLU13004 |
| institution | Swedish University of Agricultural Sciences |
| language | Swedish Inglés |
| publishDate | 2008 |
| publishDateSort | 2008 |
| record_format | eprints |
| spelling | RepoSLU130042017-11-22T09:29:38Z https://stud.epsilon.slu.se/13004/ Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia Dreimanis, Kristoffer Veterinary science and hygiene - General aspects Thrombocytopenia is a common feature in severe infection and the extent of the thrombocytopenia has been correlated to the clinical prognosis. However the pathophysiology behind this phenomenon is not completely understood. Research in the last decade has shown that thrombocytes possess several antimicrobial properties, suggesting that they might play a still unknown role in innate immunity. Moreover platelets are known to sequestrate out into lung tissue in response to stimuli like lipopolysaccharide (LPS) and septicaemia. Streptococcus pneumoniae is a common cause of severe community aquired pneumonia and septicaemia. In this project I show that platelets in vitro are activated by S. pneumoniae and can release antimicrobial peptides in response to thrombin. This occurs independent of interactions with other cells. In vivo, I show that platelet deficiency results in increased bacterial numbers within the lungs in a mouse model of S. pneumoniae pneumonia. Histopathological examination of the lungs indicates that platelets co-localise with the bacteria –and may "trap" them within lung tissue. I conclude that platelets contribute to innate immunity to S. pneumoniae pneumonia identifying a potential therapeutic target for patients with severe infection. Trombocytopeni är en vanlig företeelse i samband med svår infektion och graden av trombocytopeni hos akut sjuka patienter har visats vara korrelerad till klinisk prognos. Detta till trots är patofysiologin till detta fenomen ännu inte helt kartlagd. Det senaste årtiondets forskning har visat att trombocyter utöver sina uppgifter i koagulationen även äger flera antimikrobiska egenskaper vilket väckt frågan om trombocyter också spelar en ännu okänd roll i det cellmedierade immunförsvaret. Det har även visats att trombocyter som utsätts för stimuli som lipopolysaccharider (LPS) och septikemi sequestrerar ut i lungvävnad in vivo. Streptococcus pneumoniae är en vanlig etiologisk orsak till förvärvad pneumoni och septikemi. I detta arbete visar jag att trombocyter in vitro blir aktiverade av S. pneumoniae och frigör antimikrobiska substanser mot S. pneumoniae efter trombin stimulering, detta utan interaktioner från andra celler. In vivo visar jag att trombocytopeni under infektion leder till en snabbare bakteriell tillväxt i lungorna på möss i en modell av S. pneumoniae infektion. Histopatologisk undersökning av dessa lungor indikerar att trombocyter samlokaliserar med bakterier –och därmed eventuellt fångar bakterier i lungvävnad innan kolonisation av vävnad hinner ske. Slutsatsen är att trombocyter medverkar i det cellmedierade immunförsvaret mot S. pneumoniae pneumoni vilket potentiellt kan utgöra ett terapeutiskt mål för patienter med svår infektion. 2008-06-03 Other NonPeerReviewed application/pdf sv https://stud.epsilon.slu.se/13004/1/dreimanis_k_171122.pdf Dreimanis, Kristoffer, 2008. Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia. UNSPECIFIED, Uppsala. Uppsala: (VH) > Dept. of Biomedical Sciences and Veterinary Public Health (until 231231) <https://stud.epsilon.slu.se/view/divisions/OID-713.html> urn:nbn:se:slu:epsilon-s-9020 eng |
| spellingShingle | Veterinary science and hygiene - General aspects Dreimanis, Kristoffer Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title | Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title_full | Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title_fullStr | Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title_full_unstemmed | Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title_short | Role of platelets during innate immunity to Streptococcus pneumoniae pneumonia |
| title_sort | role of platelets during innate immunity to streptococcus pneumoniae pneumonia |
| topic | Veterinary science and hygiene - General aspects |
| url | https://stud.epsilon.slu.se/13004/ https://stud.epsilon.slu.se/13004/ |