Hostname: page-component-8448b6f56d-c47g7 Total loading time: 0 Render date: 2024-04-19T23:39:58.541Z Has data issue: false hasContentIssue false
  • English
  • Français

A comparison of fluorescein diacetate and propidium iodide staining and in vitro excystation for determining Giardia intestinalis cyst viability

Published online by Cambridge University Press:  06 April 2009

A. L. Smith  and
H. V. Smith
A. L. Smith
Affiliation:
Scottish Parasite Diagnostic Laboratory, Department of Bacteriology, Stobhill General Hospital, Glasgow G21 3UW
H. V. Smith
Affiliation:
Scottish Parasite Diagnostic Laboratory, Department of Bacteriology, Stobhill General Hospital, Glasgow G21 3UW
Get access Rights & Permissions [Opens in a new window]

Summary

The viability of 4 human isolates of Giardia intestinalis cysts using either the fluorogenic vital dyes fluorescein diacetate (FDA) and propidium iodide (PI) or in vitro excystation was assessed. Whereas viable cysts, as defined by in vitro excystation were present in each of the 4 isolates, cysts from only 3 of the 4 isolates took up the vital dyes. FDA consistently over-estimated cyst viability whilst PI under-estimated non-viable cysts when compared with in vitro excystation. Following in vitro excystation, both FDA and PI stained a proportion of unexcysted cysts indicating that FDA stained cysts which were incapable of excystation, whereas PI did not stain all cysts which were incapable of excystation. One human cyst isolate, which underwent in vitro excystation, could not be stained with either FDA or PI. In the absence of currently more specific fluorescent indicators of viability, PI alone could be used to determine the lower limit of nonviability in positive water-related samples, where small numbers of cysts are to be expected.

Keywords

Giardia intestinaliscyst viabilityexcystationstainingfluorogenic vital dyes.
Type
Research Article
Information
Parasitology , Volume 99 , Issue 3 , December 1989 , pp. 329 - 331
Copyright
Copyright © Cambridge University Press 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Akin, E. W. & Jakubowski, W. (1986). Drinking water transmission of giardiasis in the United States. Water Science and Technology 18, 219–26.CrossRefGoogle Scholar
Bhatia, V. N. & Warhurst, D. C. (1981). Hatching and subsequent cultivation of cysts of Giardia intestinalis in Diamond's medium. Journal of Tropical Medicine and Hygiene 84, 45.Google ScholarPubMed
Bingham, A. K., Jarroll, E. L., Meyer, E. A. & Radulescu, S. (1979). Giardia sp.: Physical factors of excystation in vitro and excystation vs eosin exclusion as determinants of viability. Experimental Parasitology 47, 281–91.CrossRefGoogle ScholarPubMed
Horan, P. K. & Kappler, J. W. (1977). Automated fluorescent analysis for cytotoxicity assays. Journal of Immunological Methods 18, 309–16.CrossRefGoogle ScholarPubMed
Hudson, S. J., Sauch, J. F. & Lindmark, D. G. (1988). Fluorescent dye exclusion as a method for determining Giardia cyst viability. In Advances in Giardia Research (ed. Wallis, P. M. & Hammond, B. R.), University of Calgary Press, Calgary, Canada. pp. 255–9.Google Scholar
Jones, K. H. & Senft, J. A., (1985). An improved method to determine cell viability by simultaneous staining with Fluorescein diacetate and Propidium iodide. Journal of Histochemistry and Cytochemistry 331, 77–9.CrossRefGoogle Scholar
Kasprzak, W. & Majewska, A. C. (1983). Infectivity of Giardia sp. cysts in relation to eosin exclusion and excystation in vitro. Tropenmedizin und Parasitologie 34, 70–2.Google ScholarPubMed
Schupp, D. G. & Erlandsen, S. L. (1987). A new method to determine Giardia cyst viability: Correlation of Fluorescein diacetate and Propidium iodide staining with animal infectivity. Applied and Environmental Microbiology 53, 704–7.CrossRefGoogle ScholarPubMed