Chlamydia trachomatis är en obligat intracellulär bakterie som orsakar kla-mydiainfektioner, lymphogranuloma venereum (LGV) och trakom. Klamy-dia är en av de vanligaste sexuellt överförbara infektionerna världen över och kan leda till infertilitet.
I de fyra första studierna som ingår i den här avhandlingen har vi använt ett högupplösande multilokus sekvenstypningssystem (MLST) för att under-söka klamydiabakteriens epidemiologi och vi visar att MLST ger mycket högre upplösning än konventionell ompA genotypning. I den femte studien förenklade vi metodiken genom att utveckla en multilokus typnings (MLT) mikroarray baserat på MLST systemet.
Mer detaljerat så MLST-typades konsekutiva prover insamlade i Örebro 2006 och jämfördes med prover insamlade 1999-2000, vilket visade att den nya C. trachomatis varianten (nvCT) har klonal spridning och började san-nolikt spridas i större omfattning först på senare år.
MLST-typning av LGV-prover från män som har sex med män (MSM) visade att utbrottet i Europa faktiskt var just ett monoklonalt utbrott, medan LGV tvärtom kan ha varit endemisk i USA under en längre tid.
I den tredje studien undersöktes om patienters kliniska symptom gick att korrelera till MLST-genotypen. Men vi fann ingen signifikant korrelation, vilket ytterligare understödjer den växande insikten att mer fokus måste läg-gas på patientens genetik om man vill förstå varför somliga drabbas av svåra komplikationer, medan andra klarar sig utan.
MLST-typning av prover från ett område med hög klamydiaprevalens i Nordnorge avslöjade intressanta epidemiologiska detaljer angående ovanliga genetiska varianter, nvCT och MSM, men vi fann ingen signifikant skillnad i klamydiastammarnas genetiska diversitet jämfört med andra områden i Nor-ge.
I den femte studien utvecklade vi en MLT array som ger hög upplösning samtidigt som den är snabb och kostnadseffektiv, vilket gör den till ett in-tressant alternativ vid typning av C. trachomatis.
Sammanfattningsvis så har både MLST systemet och MLT arrayen visat sig vara användbara verktyg som nu borde användas i ytterligare studier för att öka vår kunskap om klamydiabakteriens epidemiologi.
Acknowledgements
Above all, I thank Björn Herrmann for the opportunity to do this PhD. I greatly appreciate his enthusiasm and continuous support. I thank Markus Klint for helping me when I was new in the lab and for always answering my questions. I thank Björn Olsen for support when dealing with the university bureaucracy. I also thank co-authors and collaborators, all my colleagues, past as present, as well as everyone else at Mikrobiologen. Thank you for being nice and friendly!
Finally, I thank my pet rats for keeping me company after work: Snork-fröken, Filifjonkan, Isfrun, Lilla Knyttet, Mymlan, Snusmumriken, Svartkat-ten and Mårddjuret. Thank you!
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