Among pregnant women with bacterial vaginosis, the hydrolytic enzymes sialidase and prolidase are positively associated with interleukin-1beta.
OBJECTIVE
The objective of the study was to explore the mechanisms of local innate immunity induction and modulation in pregnant women with bacterial vaginosis (BV).


METHODS
A total of 200 singleton pregnant women in early gestation (12 +/- 4 weeks) with BV (Nugent 7-10) without concurrent vaginal infections with Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis, and yeast. Concentrations of vaginal interleukin (IL)-1beta and IL-8, the number of neutrophils, and the levels of sialidase and prolidase hydrolytic enzymes were determined in vaginal fluid.


RESULTS
Concentrations of vaginal IL-1beta had a strong positive correlation with levels of sialidase (P < .001) and prolidase (P < .001). Conversely, such enzymes were negatively correlated with the ratio of IL-8/IL-1beta (both P < .001) and were not significantly associated with concentrations of IL-8. Notably, the number of vaginal neutrophils had a negative correlation with sialidase (P = .007).


CONCLUSIONS
The strong induction of IL-1beta in BV-positive women appears to be associated with the production of the hydrolytic enzymes sialidase and prolidase by BV-associated bacteria. However, these 2 enzymes may inhibit the expected amplification of the proinflammatory IL-1beta cascade as evaluated by the down-regulation of the IL-8/IL-1beta ratio. A blunted response to IL-1beta signals may cause the poor rise of neutrophils, which is peculiar to BV. This impairment of local defense may contribute to increased susceptibility to adverse outcomes in BV-positive pregnant women.
Cauci
Sabina
S
Department of Biomedical Sciences and Technologies, University of Udine School of Medicine, Udine, Italy. scauci@mail.dstb.uniud.it
Culhane
Jennifer Flatow
JF
Di Santolo
Manuela
M
McCollum
Kelly
K
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D015415:Biomarkers / Q000378:metabolism; D002690:Chlamydia Infections / Q000201:enzymology / Q000276:immunology; D015331:Cohort Studies; D004150:Dipeptidases / Q000378:metabolism*; D005260:Female; D006069:Gonorrhea / Q000175:diagnosis / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate / Q000502:physiology*; D053583:Interleukin-1beta / Q000378:metabolism*; D009439:Neuraminidase / Q000378:metabolism*; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000201:enzymology / Q000276:immunology* / Q000382:microbiology; D011256:Pregnancy Outcome; D011261:Pregnancy Trimester, First; D011295:Prenatal Care; D011336:Probability; D018570:Risk Assessment; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D014247:Trichomonas Vaginitis / Q000201:enzymology / Q000276:immunology; D016585:Vaginosis, Bacterial / Q000201:enzymology / Q000276:immunology* / Q000382:microbiology
D015415:Biomarkers; D053583:Interleukin-1beta; D009439:Neuraminidase; D004150:Dipeptidases; C022449:proline dipeptidase