Impact of T. vaginalis infection on innate immune responses and reproductive outcome

J Reprod Immunol. 2009 Dec;83(1-2):185-9. doi: 10.1016/j.jri.2009.08.007. Epub 2009 Oct 21.


Trichomonas vaginalis is the most common non-viral sexually transmitted pathogen. The infection is prevalent in reproductive age women and is associated with vaginitis, endometritis, adnexitis, pyosalpinx, infertility, preterm birth, low birth weight, bacterial vaginosis, and increased risk of cervical cancer, HPV, and HIV infection. In men, its complications include urethritis, prostatitis, epididymitis, and infertility through inflammatory damage or interference with the sperm function. The infection is often asymptomatic and recurrent despite the presence of specific antibodies, suggesting the importance of the innate immune defense. T. vaginalis adhesion proteins, cysteine proteases, and the major parasite lipophosphoglycan (LPG) play distinct roles in the pathogenesis and evasion of host immunity. LPG plays a key role in the parasite adherence and signaling to human vaginal and cervical epithelial cells, which is at least in part mediated by galectins. The epithelial cells respond to T. vaginalis infection and purified LPG by selective upregulation of proinflammatory mediators. At the same time, T. vaginalis triggers an immunosuppressive response in monocytes, macrophages, and dendritic cells. The molecular mechanisms underlying reproductive complications and epidemiologic risks associated with T. vaginalis infection remain to be elucidated.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Comorbidity
  • Endometritis / etiology
  • Female
  • Humans
  • Immunity, Innate*
  • Pregnancy
  • Pregnancy Complications, Infectious / etiology
  • Reproduction
  • Sexually Transmitted Diseases, Bacterial / complications
  • Sexually Transmitted Diseases, Bacterial / immunology*
  • Sexually Transmitted Diseases, Bacterial / physiopathology
  • Trichomonas Infections / complications
  • Trichomonas Infections / immunology*
  • Trichomonas Infections / physiopathology
  • Trichomonas vaginalis / immunology*
  • Trichomonas vaginalis / pathogenicity
  • Uterine Cervical Neoplasms / etiology