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In vitro excystation of Cryptosporidium parvum

Published online by Cambridge University Press:  06 April 2009

L. J. Robertson
Affiliation:
Scottish Parasite Diagnostic Laboratory, Stobhill General Hospital, Springburn, Glasgow G21 3UW, Scotland
A. T. Campbell
Affiliation:
Scottish Parasite Diagnostic Laboratory, Stobhill General Hospital, Springburn, Glasgow G21 3UW, Scotland
H. V. Smith*
Affiliation:
Scottish Parasite Diagnostic Laboratory, Stobhill General Hospital, Springburn, Glasgow G21 3UW, Scotland
*
*Reprint requests to Dr H. V. Smith.

Summary

Protocols for in vitro excystation of oocysts of Cryptosporidium parvum, including different chemical pre-incubation steps, were compared to examine some of the biochemical triggers involved in excystation and to define an in vitro excystation protocol of a reproducibly high efficiency. Pre-incubation steps which increased the permeability of the oocysts were found to enhance excystation dynamics and pre-treatment of oocysts with saliva was found to decrease the permeability and reduce excystation. Although excystation was maximal after incubation for 4 h, sporozoites tended to lyse over this period, and maximum sporozoite recovery occurred after 30 min. The results obtained are discussed in relation to excystation protocols adopted by different research groups and a number of recommendations are given for in vitro excystation of C. parvum oocysts.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1993

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References

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