Sensibility of different larval stages of Schistosoma mansoni to the Larvae Disappearing Reaction (LDR) in murine schistosomiasis

Sensibilidade de diferentes estadios larvares de Schistosoma mansoni à Reação de Desaparecimento de Larvas (LDR) na esquistossomose murina

Abstracts

The delay produced by drug, in the process of cercaria-schistosomulum transformation, was used to verify the sensibility of different larval stages to the host cell immune responses, in vivo. The peritoneal cavity of mice, a model used for in vivo observations, was choiced for the experiments. As well characterized schistosomules, cercariae and larvae in the process of transformation were coated and arrested by host cells, and could not be recovered by simple saline washings. After 10-²M EDTA saline washings, they were released alive, with good vitality and movements. Thus, different kind of larvae in the process of adaptation of the cercaria to the host are strongly coated by immune cells, but these fail to kill the invading organisms, at least during a few hours after invasion.

Murine schistosomiasis — S. mansoni; Larval stages — Larvae disappearing reaction

ORIGINAL ARTICLES

Sensibility of different larval stages of Schistosoma mansoni to the Larvae Disappearing Reaction (LDR) in murine schistosomiasis(¹)

Sensibilidade de diferentes estadios larvares de Schistosoma mansoni à Reação de Desaparecimento de Larvas (LDR) na esquistossomose murina

Alan Lane de Melo^I; Leógenes Horácio Pereira^II; Munir Chamone^III

^IGrupo Interdepartamental de Estudos sobre Esquistossomose e Departamento de Parasitologia, ICB/UFMG

^IIDepartamento de Bioquímica-Imunologia, ICB/UFMG

SUMMARY

The delay produced by drug, in the process of cercaria-schistosomulum transformation, was used to verify the sensibility of different larval stages to the host cell immune responses, in vivo. The peritoneal cavity of mice, a model used for in vivo observations, was choiced for the experiments. As well characterized schistosomules, cercariae and larvae in the process of transformation were coated and arrested by host cells, and could not be recovered by simple saline washings. After 10-²M EDTA saline washings, they were released alive, with good vitality and movements. Thus, different kind of larvae in the process of adaptation of the cercaria to the host are strongly coated by immune cells, but these fail to kill the invading organisms, at least during a few hours after invasion.

Key words: Murine schistosomiasis — S. mansoni; Larval stages — Larvae disappearing reaction.

RESUMO

O retardo, induzido pela oxamniquine, no processo de transformação da cercária-esquistossômulo, foi utilizado, para verificar a sensibilidade de diferentes estádios larvares à resposta celular do hospedero, in vivo. A cavidade peritoneal do camundongo, um modelo utilizado para observações in vivo, foi escolhida para estes experimentos. Esquistossômulos, cercárias e larvas no processo de transformação foram seqüestrados pelas células do hospedeiro, não sendo recuperados através de perfusão da cavidade peritoneal com salina. As larvas somente foram liberadas vivas e com movimentos aptís o uso de 10^-2 M de EDTA em salina. Os diferentes estádios larvares, no processo de adaptação ao hospedeiro, são intensamente recobertos por células que, entretanto, não conseguem matar os organismos invasores, pelo menos nas primeiras horas após a invasão.

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Address for reprints:

Prof. Alan Lane de Melo

GIDE — ICB/UPMG

Caixa Postal 2486, 30000 Belo Horizonte, MG, Brasil

Recebido para publicação em 2/12/1985.

• 1. CLEGG, J. A. & SMITHERS, S. B. Death of schistosome cercariae during penetration of the skin. II Penetration of mammalian skin by Schisosoma mansoni. Parasitology, 58: 111-128, 1968.
• 2. EVELAND, L. K. Schistosoma mansoni: conversion of cercaria to schistosomula. Exp. Parasit., 32: 261-264, 1972.
• 3. GORDON, R. M. & GRIFFITHS, R. B. Observations on the means by which the cercariae to Schistosoma mansoni penetrate mammalian skin together with an account to certain morphological changes observed in the newly penetrated larvae. Ann. trop. Med. Parasti., 45: 227-243, 1951.
• 4. KASSIS, A. E.; WARREN, K. S. & MAHMOUD, A. A. F. Antibody dependent complement mediated killing of schistosomule in peritoneal diffusion chambers in mice. J. Immunol., 123: 1659-1662, 1979.
• 5. MELO, A. L.; PEREIRA, L. H. & CORRÊA, M. O. R. In vivo cercaria-schistosomulum transformation: inhibitory effect of oxamniquine. Trans. roy. Soc. trop. Med. Hyg., 72: 158-159, 1978.
• 6. MELO, A. L. & PEREIRA, L. H. Inhibitory effect of oxamniquine on the detachment of the tail of Schistosoma mansoni cercariae. J. Parasit., 66: 1067-1068, 1980.
• 7. MELO, A. L.; PEREIRA, L. H. & CHAMONE, M. -The effeet of a previous Schistosoma mansoni infection on schistosomulum recovery from the peritoneal cavity of laboratory mice. Trans. roy. Soc. trop. Med Hyg., 74; 827, 1980.
• 8. PELLEGRINO, J. & SIQUEIRA, A. P. Técnica para perfusão para colheita de Schistosoma mansoni em cobaias experimentalmente infestadas. Rev. Bras. Malar., 8: 589-597, 1956.
• 9. PEREIRA, L. H.; COELHO, P. M. Z.; FONSECA, J. J. A.; BREDT, A. & PELLEGRINO, J. Migration of Schistosoma mansoni larvae in the albino mouse. Rev. Inst. Med. trop. S. Paulo, 14: 306-309, 1972.
• 10. PEREIRA, L. H.; PELLEGRINO, J.; VALADARES, T. E.; MELLO, R. T. & COELHO, P. M. Z. A new approach for screening prophylactic agents in schistosomiasis. Rev. Inst. Med. trop. S. Paulo, 16: 123-126, 1974.
• 11. PEREIRA, L. H.; PELLEGRINO, J. & MELLO, R. T. Activity ol known antischistosomal agents on early developing forms of S. mansoni. J. Parasit., 61: 249-252, 1975.
• 12. SMITHERS, S. R. & TERRY, R .J. The Immunology of Schistosomiasis. Advanc. Parasit., 7: 41-93, 1969.
• 13. SMITHERS, S. R. & TERRY, R. J. The Immunology of Schistosomiasis. Advanc. Parasit., 14: 399-422, 1976.
• 14. SMITHERS, S. R. & GAMMAGE, K. Recovery of Schistosoma mansoni from the skin, lungs and hepatic portal system of naive mice and mice previously exposed to S. mansoni evidence for two phases of parasite attrition in immune mice. Parasitology, 80: 289-300, 1980.
• 15. STIREWALT, M. A. Schistosoma mansoni: cercaria to schistosomule. Advanc. Parasit., 12: 115-182, 1974.

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This study was supported by CNPq-Brazil, and by the World Health Organization — Switzerland

Publication Dates

• Publication in this collection
  10 Oct 2012
• Date of issue
  Dec 1986