Skip to main content
×
Home
    • Aa
    • Aa

Migration of the schistosomula of Schistosoma mansoni in mice vaccinated with radiation-attenuated cercariae, and normal mice: an attempt to identify the timing and site of parasite death

  • R. A Wilson (a1), Patricia S. Coulson (a1) and B Dixon (a2)
Abstract
SUMMARY

The migration of the schistosomula of Schistosoma mansoni labelled with [75Se] has been followed from the skin to the hepatic portal system. Parasites were detected in all mouse tissues by compressed organ autoradiography. Two separate experiments were performed to track parasites in normal mice, and in mice previously vaccinated with irradiated cercariae. In normal mice, the profile of numbers of autoradiographic foci detected in the skin, lungs, systemic and splanchnic organs was described with time post-infection. The distribution of parasites to systemic organs, following exit from the lungs, paralleled the fractional distribution of cardiac output. Accumulation of schistosomula in the hepatic portal system was complete by day 21 post-infection. Only 2–3 passes of parasites around the vascular system would be required to produce the hepatic portal population. No significant decline in total foci was detected in the first 12 days post-infection. The majority of parasite elimination appeared to occur in the lungs as late as day 21, with lesser proportions in the systemic organs and skin infection site. The pattern of migration in vaccinated mice was similar to that in normal animals. One difference observed was the longer duration of stay in the skin; however, the majority of parasites eventually reached the lungs. The systemic phase of migration occurred on a reduced scale, as did accumulation of parasites in the hepatic portal system. The decline in total foci in vaccinated mice commenced approximately 7 days earlier than in normal mice and proceeded to a lower end-point. Again the majority of parasite elimination appeared to occur in the lungs with lesser proportions in the systemic organs and skin infection site. It is suggested that resistance to reinfection in vaccinated mice has two additive components which combine to retard the migration of schistosomula within the vasculature, preventing them from reaching the hepatic portal system.

Copyright
Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

K. L. Miller & S. R. Smithers (1980). Schistosoma mansoni: the attrition of a challenge infection in mice immunized with highly irradiated live cercariae. Experimental Parasitology 50, 212–2 1.

L. Olivier & M. A. Stirewalt (1952). An efficient method for exposure of mice to cercariae of Schistosoma mansoni. Journal of Parasitology 38, 1923.

M. A. Smith . & J. A. Clegg (1984). Schistosoma mansoni: decay of resistance induced by gamma irradiated cercariae in the mouse. Transactions of the Royal Society of Tropical Medicine and Hygiene 78, 190–2.

R. A. Wilson & P. S. Coulson (1984). The effect of softwood sawdust bedding on the maturation of an infection of Schistosoma mansoni in mice exposed to cercariae via the tail or abdominal skin. Transactions of the Royal Society of Tropical Medicine and Hygiene 78, 411–12.

R. A. Wilson , P. S. Coulson & S. M. McHugh (1983). A significant part of the ‘oncomitant immunity’ of mice to Schistosoma mansoni is the consequence of a leaky hepatic portal system, not immune killing. Parasite Immunology 5, 595601.

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Parasitology
  • ISSN: 0031-1820
  • EISSN: 1469-8161
  • URL: /core/journals/parasitology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×