RESUMO
The interaction between each one of Trichomonas vaginalis and Tritrichomonas foetus with their hosts is a complex process in which components associated to the cell surfaces of both parasites and host epithelial cells, and also to soluble components found in vaginal/urethral secretions, are involved. Either cytoadhesion or the cytotoxicity exerted by parasites to host cells can be dictated by virulence factors such as adhesins, cysteine proteinases, laminin-binding proteins, integrins, integrin-like molecules, a cell detachment factor, a pore-forming protein, and glycosidases among others. How trichomonads manipulate informations from the extracellular medium, transduce such informations, and respond to them by stimulating the activities of some surface molecules and/or releasing enzymes are the aspects concerning trichomonal virulence which are here briefly reviewed and discussed.
Assuntos
Humanos , Animais , Masculino , Feminino , Transdução de Sinais/fisiologia , Tricomoníase/diagnóstico , Trichomonas/fisiologia , Células Epiteliais , Matriz Extracelular , Interações Hospedeiro-Parasita/fisiologia , Ferro/fisiologia , Trichomonas vaginalis/citologia , Trichomonas vaginalis/patogenicidade , Trichomonas vaginalis/fisiologia , Trichomonas/citologia , Trichomonas/patogenicidade , Sistema Urogenital/parasitologiaRESUMO
In in vitro assay the hemolytic activity of live isolates and clones of trichomonas gallinae was investigated. The fresh isolates and clones were tested against human erythrocytes of groups A, B, AB and O, and against erythrocytes of six adult animals of different species (rabbit, rat, chicken, horse, bovine and sheep). Results showed that each of the isolates and clones tested lysed all human blood groups, as well as rabbit, rat, chicken, horse, bovine and sheep erythrocytes. No hemolysin released by the parasites could be identified. Parasite culture supernatants of hemolysis assays, tested in the presence of human erythrocytes did not induce any hemolytic activity. Trichomonads culture supernatants from 18, 24, and 48 hr extracts of sonicated parasites or cold killed organisms tested with human erythrocytes did not exhibit hemolysis. Although an hemolytic activity of T. gallinae was clearly demonstrated, a relationship between hemolysis and cell pathogenicity is not yet clearly established
Assuntos
Aves/parasitologia , Técnicas In Vitro , Trichomonas/patogenicidade , Hemólise/fisiologiaRESUMO
Trichomonas gallinae (Rivolta, 1878) is a parasitic protozoan of the upper digestive tract and various organs of different avian groups, being common among the columbids, was isolated described and its prevalence studies in the southern brazilian state, Rio Grande do Sul. The morphology study of the live speciemens done by examinations of fresh and stained specimens, showed that the T. gallinae isolated has the same morphological characteristics as the upper digestive tract trichomonads previously described by other authors