Hostname: page-component-78c5997874-lj6df Total loading time: 0 Render date: 2024-11-06T11:06:31.614Z Has data issue: false hasContentIssue false

Studies on the cryopreservation of eggs of Angiostrongylus cantonensis

Published online by Cambridge University Press:  05 June 2009

Shoji Uga
Affiliation:
Department of Medical Zoology, Kobe University School of Medicine, Kobe 650, Japan
Kazuyoshi Araki
Affiliation:
Department of Medical Zoology, Kobe University School of Medicine, Kobe 650, Japan
Takeo Matsumura
Affiliation:
Department of Medical Zoology, Kobe University School of Medicine, Kobe 650, Japan
Noboru Iwamura
Affiliation:
International Center for Medical Research, Kobe 650, Japan

Abstract

The possibility of cryopreserving the eggs of Angiostrongylus cantonensis collected from the uterus of female worms was investigated. Eggs were cultured in NCTC 109 medium containing 50% rat serum, and various growth stages, from one-cell eggs to embryonated eggs, were used in this study.

As a cryoprotective agent, dimethylsulphoxide (Me2SO) was added to the medium at a final concentration of 1 M. Eggs suspended in 0·2 ml of the medium at 37°C were cooled to 0°C at a rate of l°C min−1, then an equal volume of 2M-Me2SO solution was added. After equilibration for 15min, the freezing procedures were started. In the freezing procedures, the effectiveness of (i) a seeding process, (ii) different cooling and warming rates and (iii) the relationship between the growth stages of the eggs and their tolerance to freezing at −20°C were investigated.

It was found the highest level of survival could be obtained with 32-cell eggs cooled at a rate of 0·3° C min−1 or more slowly with seeding at −4°C and warming at a rate of 5°C min−1. Survival was influenced more by cooling rate than by warming rate.

Using these optimum conditions, the survival of eggs was then investigated following cooling to various temperatures. While more than 50% of eggs were found to survive cooling to −30–C, extremely low survival was noted from lower temperatures.

Type
Research Papers
Copyright
Copyright © Cambridge University Press 1983

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

REFERENCES

Boray, J. C. & Enigk, K. (1964) Laboratory studies on the survival and infectivity of Fasciola hepatica and F. gigantica metacercariae. Zeitschrift fur Tropenmedizin und Parasitologie, 15, 324331.Google ScholarPubMed
Campbell, W. C, Blair, L. S. & Egerton, J. R. (1972) Motility and infectivity of Haemonchus contortus larvae after freezing. Veterinary Record, 91, 13.CrossRefGoogle ScholarPubMed
Campbell, W. C. & Thomson, B. M. (1973) Survival of nematode larvae after freezing over liquid nitrogen. Australian Veterinary Journal, 49, 110111.CrossRefGoogle ScholarPubMed
Cruthers, L. R., Weise, R. W. & Hansen, M. F. (1974) Topography of Ascaridia galli eggs exposed to low temperatures or cryoprotectants as shown by scanning electron microscopy. Journal of Parasitology, 60, 632635.CrossRefGoogle ScholarPubMed
Ham, P. J., James, E. R. & Bianco, A. E. (1979) Onchocerca spp.: Cryopreservation of microfilariae and subsequent development in the insect host. Experimental Parasitology, 47, 384391.CrossRefGoogle ScholarPubMed
Ham, P. J., Townson, S., James, E. R. & Bianco, A. E. (1981) An improved technique for the cryopreservation of Onchocerca microfilariae. Parasitology, 83, 139146.CrossRefGoogle ScholarPubMed
James, E. R. & Farrant, J. (1977) Recovery of infective Schistosoma mansoni schistosomula from liquid nitrogen: A step towards storage of a live schistosomiasis vaccine. Transactions of the Royal Society of Tropical Medicine and Hygiene, 71, 498500.CrossRefGoogle ScholarPubMed
James, E. R. (1981) Schistosoma mansoni: Cryopreservation of schistosomula by two-step addition of ethanediol and rapid cooling. Experimental Parasitology, 52, 105116.CrossRefGoogle ScholarPubMed
Lok, J. B., Cupp, E. W., Braide, E. I. & Bernardo, M. J. (1980) Aedes aegypti as a surrogate host for Onchocerca spp. American Journal of Tropical Medicine and Hygiene, 29, 382388.CrossRefGoogle ScholarPubMed
Schiller, E. L, Turner, V. M., Marroquin, H. F. & D'antonio, R. (1979) The cryopreservation and in vitro cultivation of larval Onchocerca volvulus. American Journal of Tropical Medicine and Hygiene, 28, 9971009.CrossRefGoogle ScholarPubMed
Taylor, E. L. (1949) The epidemiology of fascioliasis in Britain. Proceedings XlVth International Veterinary Congress.Google Scholar
Toyoda, Y. & Takeshima, T. (1978) Cryopreservation of mouse embryos fertilized in vitro. Kachikuhanshokushi, 24, 3435. [In Japanese.]Google Scholar
Uga, S. & Matsumura, T. (1979) Studies in the cryopreservation of Trichomonas vaginalis. Effects of cryoprotective agent and “seeding” of ice. Japanese Journal of Parasitology, 28, 421426.[In Japanese.]Google Scholar
Uga, S. & Matsumura, T. (1982) In vitro cultivation of Angiostrongylus cantonensis eggs. Japanese Journal of Parasitology, 31, 5966.Google Scholar
Van Wyk, J. A., Gerber, H. M. & Van Aardt, W. P. (1977) Cryopreservation of the infective larvae of the common nematodes of ruminants. Onderstepoort Journal of Veterinary Research, 44, 173194.Google ScholarPubMed
Whittingham, D. G. (1971) Survival of mouse embryos after freezing and thawing. Nature, 233, 125126.CrossRefGoogle ScholarPubMed
Whittingham, D. G., Leibo, S. P.Mazur, P. (1972) Survival of mouse embryos frozen to –196 and –269°C. Science, 178, 411–114.CrossRefGoogle Scholar