Genetic variation in the interleukin-8 gene promoter and vaginal concentrations of interleukin-8 are not associated with bacterial vaginosis during pregnancy

Interleukin-8 (IL-8) may play a role in the activation of the vaginal immune system during bacterial vaginosis. However, contradictory results were obtained regarding the involvement of IL-8 in the immunological response during bacteria vaginosis. These apparently contradictory results could be due to different genetic variations of the study groups. Since some gene polymorphisms may affect the level of IL-8 production, the aim of this study was to determine whether the frequency IL-8 promoter alleles and levels of IL-8 in vaginal fluid are associated with bacterial vaginosis during pregnancy. Genotyping for IL-8 polymorphisms in the promoter region of the gene was performed in 34 pregnant women with asymptomatic bacterial vaginosis matched for gestational age with 38 pregnant women without vaginosis. Additionally, vaginal IL-8 levels were assayed by the dual monoclonal antibody sandwich enzyme-linked immunosorbent assay technique. The frequencies of the three polymorphisms were not significantly different between control women and women with bacterial vaginosis. In addition, there was no linkage disequilibrium between the polymorphisms. Furthermore, there was no statistical difference in median vaginal levels of IL-8 between both groups. Neither the frequencies of IL-8 polymorphic alleles nor levels of IL-8 in vaginal fluid were associated with bacterial vaginosis.