Neisseria gonorrhoeae downregulates expression of the human antimicrobial peptide LL-37.
Neisseria gonorrhoeae is a human pathogen causing the sexually transmitted disease gonorrhoeae. The bacteria preferentially attach to and invade epithelial cells of the genital tract. As these cells previously have been shown to express the human cathelicidin LL-37, we wanted to investigate the role of LL-37 during N. gonorrhoeae infection. The cervical epithelial cell line ME180 was utilized and the expression of LL-37 was confirmed on both peptide and transcriptional levels. Moreover, LL-37 exhibited potent in vitro activity against N. gonorrhoeae. Interestingly, the transcript and peptide levels of LL-37 were downregulated during infection, according to quantitative real-time polymerase chain reaction (PCR) and immunocyto-chemistry. The downregulation was most prominent with pathogenic strains of Neisseria, while non-pathogenic strains such as Neisseria lactamica and Escherichia coli only exhibited moderate effects. Heat-killed N. gonorrhoeae had no impact on the downregulation, emphasizing the importance of live bacteria. The results in this study suggest that pathogenic Neisseria may gain a survival advantage in the female genital tract by downregulating LL-37 expression.
Bergman
Peter
P
Department of Medical Biochemistry and Biophysics (MBB), Karolinska Institutet, Stockholm, Sweden.
Johansson
Linda
L
Asp
Vendela
V
Plant
Laura
L
Gudmundsson
Gudmundur H
GH
Jonsson
Ann-Beth
AB
Agerberth
Birgitta
B
D000900:Anti-Bacterial Agents / Q000096:biosynthesis / Q000494:pharmacology; D023181:Antimicrobial Cationic Peptides / Q000096:biosynthesis* / Q000494:pharmacology; D002460:Cell Line; D015536:Down-Regulation; D004847:Epithelial Cells / Q000382:microbiology; D004926:Escherichia coli / Q000472:pathogenicity; D005260:Female; D006801:Humans; D009344:Neisseria gonorrhoeae / Q000472:pathogenicity*; D042806:Neisseria lactamica / Q000472:pathogenicity; D012333:RNA, Messenger / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D054804:Cathelicidins
D000900:Anti-Bacterial Agents; D023181:Antimicrobial Cationic Peptides; D012333:RNA, Messenger; D054804:Cathelicidins