Specific parasitism of purified vaginal epithelial cells by Trichomonas vaginalis

Abstract

Human vaginal epithelial cells (VECs) from vaginal swabs obtained from normal women or from patients with trichomoniasis were purified, and VEC parasitism by Trichomonas vaginalis was examined. Trichomonads bound equally well to live or dead VECs, and up to 20% of VECs were parasitized. Trichomonal cytadherence of human VECs was time, temperature, and pH dependent. Saturation binding levels of live trichomonads to VECs gave -2 organisms adherent to parasitized VEC. No differences in cytadherence levels were detected by different isolates to VECs from the same patient compared with adherence to VECs from normal individuals. Trypsinized, live T. vaginalis organisms failed to recognize VECs. A ligand assay identified four adhesin candidates, and only organisms without a prominent immunogen on the surface (negative phenotype) cytadhered to VECs and synthesized the adhesins, confirming the results of a recently published report by us on adherence to HeLa cell monolayers (J. F. Alderete and G. E. Garza, Infect. Immun. 56:28-33, 1988). These data show the ability of T. vaginalis to parasitize human vaginal epithelial cells in a specific receptor-ligand manner.Cytadherence assay. Optimization of conditions for mea-2558

Adherence of Tritrichomonas foetus to bovine vaginal epithelial cells

“…Monoclonal antibodies to glycoprotein antigens of T. vaginalis usually reacted with only T. vaginalis in live-cell immunofluorescence experiments and also agglutinated the organism, suggesting surface recognition (5,6,8,35). Alderete et al (1,4) have shown that four surface proteins of T. vaginalis bind to human cells. The putative adhesins ranged in relative molecular mass from 65 to -21 kDa.…”

“…Both Trichomonas vaginalis (7,36) and T. foetus (7) were shown to be cytotoxic to tissue culture cell lines, but T. foetus caused about half as much damage as T. vaginalis (7). A human pathogen, T. vaginalis adheres to tissue culture cell lines (21,36) and recently was shown to also adhere to human vaginal epithelial cells (VECs) (1). Since T. foetus parasitizes the bovine vaginal surface (40), we investigated the interaction of trichomonads with bovine VECs and the ability of bovine antibodies to prevent this interaction.…”

Vaginal leukocyte characteristics in urogenital trichomoniasis

“…The washing technique used for purification of leukocytes from vaginal exudate samples was 398 a modification of the method of Alderete et a1. (2). Epithelial cells and debris were removed by filtration and the lysis of trichomonads by serum complement (9) was utilized for elimination of the parasites from the leukocyte suspension.…”

Relatedness of structures of a major immunogen in Trichomonas vaginalis isolates

“…Several observations were made in these early studies. For example, the discovery of phenotypic variation for the C20A3-reactive molecule and other immunogens of the pathogenic human trichomonads of type II isolates (4,9,10) was important for establishing relationships between specific phenotypes and virulence properties (5,7,9). More recent findings support the notion of alternating expression of groups of proteins on the surface of T. vaginalis (2,3).…”