Prevotella bivia as a source of lipopolysaccharide in the vagina.
OBJECTIVE
To compare vaginal lipopolysaccharides (LPS) concentrations between patients with and without bacterial vaginosis (BV), to evaluate the correlation between Prevotella bivia colonization density and LPS concentration, and to determine the impact of LPS on loss of dopamine neurons (DA).


METHODS
Vaginal washes obtained from patients with (n=43) and without (n=59) BV were tested for quantity of P. bivia cells using quantitative PCR and for concentrations of LPS using the Limulus Amebocyte Lysate gel clot method. Prevotella bivia, Gardnerella vaginalis and Escherichia coli sonicated cell extracts were also tested for LPS production. DA neuron cells obtained from embryonic day (E) 14.5 pregnant rats were exposed to fluid from eight vaginal washes; tyrosine hydrolase immunoreactive staining was applied for visualization and cell counts.


RESULTS
The median LPS concentrations were dramatically higher among patients who had symptoms of BV compared to those who did not have symptoms (3235.0 vs 46.4 EU/ml, respectively, P<0.001); patients who had BV also had much higher colonization densities of P. bivia (0.06+/-0.36 vs 5.4+/-2.2 log(10) CFU/ml, respectively, P<0.001). Prevotella bivia cell lysates resulted in a higher LPS concentration (10,713.0+/-306.6 EU/ml) than either E. coli (4679.0+/-585.3 EU/ml) or G. vaginalis (0.07+/-0.01 EU/ml of LPS). The loss of DA neuron was 20-27% in cultures treated with vaginal washes from BV-negative patients and 58-97% in cultures treated with vaginal washes from patients with BV.


CONCLUSIONS
P. bivia produces high LPS concentration, which may create a toxic vaginal environment that damages DA neurons.
Rush University Medical School/Stroger Hospital of Cook County, Division of Infectious Diseases, Chicago, IL, USA. aaroutch@rush.edu
Alla
A
Aroutcheva
Zaodung
Z
Ling
Sebastian
S
Faro
D000818:Animals; D001427:Bacterial Toxins / Q000633:toxicity; D002478:Cells, Cultured; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000302:isolation & purification / Q000378:metabolism; D005260:Female; D006194:Gardnerella vaginalis / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D008033:Limulus Test; D008070:Lipopolysaccharides / Q000032:analysis*; D009474:Neurons / Q000187:drug effects; D016133:Polymerase Chain Reaction / Q000379:methods; D018720:Prevotella / Q000302:isolation & purification* / Q000378:metabolism*; D051381:Rats; D014621:Vagina / Q000737:chemistry* / Q000382:microbiology*; D016585:Vaginosis, Bacterial / Q000382:microbiology* / Q000473:pathology*
D001427:Bacterial Toxins; D008070:Lipopolysaccharides