Genetic diversity inTrichomonas vaginalis

Abstract

Recent advances in genetic characterisation of Trichomonas vaginalis isolates show that the extensive clinical variability in trichomoniasis and its disease sequelae are matched by significant genetic diversity in the organism itself, suggesting a connection between the genetic identity of isolates and their clinical manifestations. Indeed, a high degree of genetic heterogeneity in T vaginalis isolates has been observed using multiple genotyping techniques. A unique two-type population structure that is both local and global in distribution has been identified, and there is evidence of recombination within each group, although sexual recombination between the groups appears to be constrained. There is conflicting evidence in these studies for correlations between T vaginalis genetic identity and clinical presentation, metronidazole susceptibility, and the presence of T vaginalis virus, underscoring the need for adoption of a common standard for genotyping the parasite. Moving forward, microsatellite genotyping and multilocus sequence typing are the most robust techniques for future investigations of T vaginalis genotype-phenotype associations.

Humoral and T cell–mediated immune response against trichomoniasis

“…The presence of TVV in clinical isolates of T. vaginalis led to higher levels of in vitro adherence of parasite to the VECs, and more severe clinical disease than TVV‐negative isolates. Also, TVV‐2‐positive isolates were more pathogenic than TVV‐1‐positive ones . However, in another study, all the fresh parasite isolates from 15 symptomatic and 15 asymptomatic women were found to harbour TVV, while it was observed only in 7 isolates following long‐term culture.…”

“…The study suggested that it might not be the only virulence marker . In simultaneous trichomoniasis and bacterial vaginosis, the presence of TVV enhances the pro‐inflammatory response . Previous studies have shown that the presence of TVV is associated with variable expression of T .…”

“…91,92 TVV may enhance the pathogenicity of T. vaginalis via upregulation of the CP expression, which enhances cytoadherence, cytotoxicity and degradation of basement membrane. 91,92 The presence of TVV in clinical isolates of T. vaginalis led to higher levels of in vitro adherence of parasite to the VECs, and more severe clinical disease than TVVnegative isolates. Also, TVV-2-positive isolates were more pathogenic than TVV-1-positive ones.…”

The biology of Trichomonas vaginalis in the light of urogenital tract infection

“…Maybe these multinuclear cells, which are rarely observed in routine lab culture, undergo some kind of meiotic division after two cells fused. Tentative evidence comes from a large scale analysis that analysed the genetic diversity in T. vaginalis [68]. The complexity and repetitive nature of the Trichomonas genome generally raises the question of how the parasite survives in the wild without chromosomal recombination.…”

Neglected Parasitic Infections in the United States: Trichomoniasis

“…This finding could lead to identification of genetic markers for resistance and the ability to develop molecular tests for isolates from persons who experience treatment failure, which could expedite results on drug susceptibility and improve patient care. Further research on the association of genetic markers with parasite virulence and persistence is also needed, including the effects of parasite infection with the T. vaginalis virus 60,61…”