Contact-dependent cytopathogenic mechanisms of Trichomonas vaginalis

Journal Article · Sun Dec 01 04:00:00 EST 1985 · Infect. Immun.; (United States)

OSTI ID:5731772

Krieger, J N; Ravdin, J I; Rein, M F

The cytopathogenic mechanisms of Trichomonas vaginalis have been debated since the 1940s. We examined the following three proposed pathogenic mechanisms: contact-dependent extracellular killing, cytophagocytosis, and extracellular cytotoxins. Serial observations of Chinese hamster ovary (CHO) cell monolayers exposed to trichomonads revealed that (i) trichomonads form clumps, (ii) the clumps adhere to cells in culture, and (iii) monolayer destruction occurs only in areas of contact with T. vaginalis. Kinetic analysis of target cell killing by trichomonads revealed that the probability of CHO cell death was related to the probability of contact with T. vaginalis, supporting the observation by microscopy that trichomonads kill cells only by direct contact. Simultaneous studies of /sup 111/indium oxine label release from CHO cells and trypan blue dye exclusion demonstrated that T. vaginalis kills target cells without phagocytosis. Filtrates of trichomonad cultures or from media in which trichomonads were killing CHO cells had no effect on CHO cell monolayers, indicating that trichomonads do not kill cells by a cell-free or secreted cytotoxin. The microfilament inhibitor cytochalasin D (10 micrograms/ml) inhibited trichomonad killing of CHO cell monolayers by 80% (P less than 0.0001). In contrast, the microtubule inhibitor vinblastine (10(-6) M) caused only 17% inhibition of trichomonad destruction of CHO cell monolayers (P less than 0.020), whereas colchicine (10(-6) M) had no effect. T. vaginalis kills target cells by direct contact without phagocytosis. This event requires intact trichomonad microfilament function; microtubule function appears not to be essential.

• OSTI ID: 5731772
• Journal Information: Infect. Immun.; (United States), Journal Name: Infect. Immun.; (United States) Vol. 3; ISSN INFIB
• Country of Publication: United States
• Language: English

Related Subjects

550901* -- Pathology-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
ALKALOIDS
ANIMAL CELLS
ANIMALS
ANTIMITOTIC DRUGS
ANTIPYRETICS
AROMATICS
AZAARENES
AZINES
AZOLES
BETA DECAY RADIOISOTOPES
CELL CONSTITUENTS
CELL KILLING
CENTRAL NERVOUS SYSTEM DEPRESSANTS
CHO CELLS
COLCHICINE
DAYS LIVING RADIOISOTOPES
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
HETEROCYCLIC COMPOUNDS
HYDROXY COMPOUNDS
INDIUM 111
INDIUM ISOTOPES
INDOLES
INFECTIVITY
INTERMEDIATE MASS NUCLEI
INVERTEBRATES
ISOMERIC TRANSITION ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MICROORGANISMS
MICROTUBULES
MINUTES LIVING RADIOISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
ORGANIC NITROGEN COMPOUNDS
OXINE
PHAGOCYTOSIS
PROTOZOA
PYRIDINES
PYRROLES
QUINOLINES
RADIOISOTOPES
TRACER TECHNIQUES
VINBLASTINE