Detection of Fusobacterium nucleatum in chorionic tissues of high-risk pregnant women

This study was undertaken to investigate the existence of a periodontopathic bacterium, Fusobacterium nucleatum, in chorionic tissues of pregnant women, and the effects of F. nucleatum on human chorion-derived cells.

Oral and chorionic tissue samples were collected from 24 high-risk pregnant women and 15 normal pregnant women. The presence of F. nucleatum in the samples was detected using polymerase chain reaction. Chorion-derived cells and Toll-like receptor (TLR)-2 or TLR-4 gene-silenced chorion-derived cells were stimulated with F. nucleatum lipopolysaccharide (LPS). Interleukin (IL)-6 and corticotrophin-releasing hormone (CRH) levels in the culture supernatants were measured using ELISA.

F. nucleatum was detected in all oral samples and seven chorionic tissues from the high-risk pregnant women, but was not detected in chorionic tissues from the normal pregnant women. F. nucleatum LPS significantly increased IL-6 and CRH secretion by chorion-derived cells. The F. nucleatum LPS-induced IL-6 and CRH levels were significantly reduced in TLR-2 or TLR-4 gene-silenced chorion-derived cells.

We suggest that F. nucleatum is detected in chorionic tissues of high-risk pregnant women, but not in chorionic tissues of normal pregnant women, and that F. nucleatum induces IL-6 and CRH production via both TLR-2 and TLR-4 in chorion-derived cells.