Holanda, J. E.

Pellegrino, J.

English

Cadernos Espinosanos (E-Journal)

.éRev. Inst. Med. trop. São Paulo 16(3):127-131, maio-junho, 1974 UDG 616.995.122.22 INFECTIVITY OF SCHISTOSOMULA (SCHISTOSOMA MANSONI) RECOVERED FROM THE SKIN AND THE LUNG OF INFECTED MICE J. e. HOLANDA (1 ) and J. PELLEGRINO (2 ) SUMMARY Schistosomula (Schistosoma mansoni) were obtained by exposing the abdo-minal skin of mice to about 3,000 cercariae and by removing the exposed area .( after 30 min) and mincing the tissue in saline. Three groups of 10 mice were then injected (50 larvae per animal) by the subcutaneous, intraperitoneal and intravenous routes. The percentages of worms recovered as adult schistosomes were 25. 4, 29. 2 and 19. 6, respectively. Schistosomula, recovered from the lung of mice (4 days after exposure to 3,000 cercariae) were injected intravenously (50 larvae per animal) into 10 mice. The percentage of worm recovery was 64.8. INTRODUCTION Relatively, little is known about the infec-tive capacity of schistosomula (Schistosoma mansoni) obtained in vit,·o and in vivo. STIREWALT & UY 11 mention that schistoso-mula obtained in vitro produce infections in mice following intravenous, but not intra-cutaneous or intraperitoneal inoculations. PEREIRA 9. and PEREIRA et a!. 10 demonstrated that schistosomula collected from lungs of infected mice ( 4-day-old larvae) and li ver ( 10-day-old larvae) are infective to mice when injected by subcutaneous and intra-peritoneal routes. HOLANDA, PELLEGRINO & GAZZINELLI 4 showed that a high percentage of recovery ( about 40%) is reached when schistosomula obtained in vitro are injected in mice by the subcutaneous and intravenous routes. M-oREIRA et a!. 6 were not able to infect adult hamsters ( cheek pouch) and 11ewly-born hamsters (skin) using schisto-somula obtained from the lung of mice (3 to 5-day-old larvae). The present paper deals with the infective capacity of schistosomula, obtained in vivo, when injected by the subcutaneous, intra-peritoneal and intravenous routes to mice. MATERIAL AND METHODS Cercariae of S. mansoni - ln all experi-ments cercariae (L.E. strain, Belo Horizon-te) of S. mansoni were shed by infected Biomphalaria glabrata, maintained and rear-ed in the laboratory. Recovery of schistosomula from skin -The method used was similar to those des-cribed by STIREWALT 11, CLEGG 2 , and CLEGG & SMITHERS 3 • A standard glass ring with This paper was supported, in part, by the "Conselho Nacional d•e Pesquisas" (MINIPLAN), Bra-zil, and the U .S. Army (Grant DADA 17-73-G-9378) (1) Department of Zoology and Parasitology, Federal University of Minas Gerais. Fellow from the "Conselho Nacional de Pesquisas" {2) Schistosomiasis Research Unit, Federal University of Minas Gerais, Belo Horizonte, Brazi!. Fellow from the "Conselho Nacional de Pesquisas" Contribution no. 50 from the Schistosomiasis Research Unit. Address fOr reprints: Caixa Postal 1404, 30000 - Belo Horizonte, Brazil 127 HOLANDA, J. C. & PELLEGRINO, J. - Infectivity of schistosomula (Schistosorna rnansoni) recover-ed from the skin and the Iung of infected mice. Rev. Inst. Med. trop. São Paulo 16:127-131, 1974. an inside diameter of 2. O cm was placed on the shaved abdominal skin of 5 anesthetized mice. The ring was filled with 2 mi of a heavy cercaria! suspension ( about 3,000 cer-cariae) which was left in contact with the skin for 30 min. The animais were killed and the area of the skin covered by the glass ring was washed with saline and ra-pidly excised. The schistosomula were recover-ed from the pieces of the skin by chopping the skin into small pieces which were incubat-ed in saline for 1 hour at 37°C. Recovery of schistosomula from lungs -Mice were killed 4 days after exposure to about 3,000 cercariae per animal. The ani-mais were opened and 10 ml of saline con-taining O .1 mg heparin per ml was injected into the right venticle to perfuse the lungs. The left ventricle was punctured to allow the perfusate to flow away. The perfused lungs were chopped into small fragment ( 1 mm3 ). The lung fragments were incubated in saline for 1 hour at 37°C. During this time schis-tosomula crowled out from the lung capilla-ries. Finally, lung fragments were separat-ed from the schistosomula by passing the suspension through a stainless steel wire (mesh 60). lnfection of mice - The animais were injected with 50 schistosomula. According to each experiment the larvae were injected by the subcutaneous, intraperitoneal ·and in-travenous routes. ln the last case the larvae were injected via the dorso cervical veins of the tail. Recovery of schistosomes - The method of PELLEGRINO & SIQUEIRA 8, adapted to mice, was used to perfuse the liver and me-senteric vessels, 7 weeks after infection with schistosomula. ln case the animais had been infected intraperitoneally, after the perfusion the peritoneum and intestinal loops were washed carefully, as mentioned by BRENER J, with saline. Oogram - The oogram was performed in ali animais following the technique of PELLEGRINO & FARIA·. 128 RESULTS AND COMMENTS The results obtained after injecting schiE-tosomula recovered from skin, in mice, are summarized in Table 1. As can be seen. the mean worm recoveries were 12. 7 + 4. 7, 14.6 + 6.1 and 9.8 + 3.8 for the sub-cutaneous, intraperitoneal and intravenous routes. The statistical analysis showed that only the comparison between the mean worm recovery from the animais injected by intra-peritoneal and intravenous routes was signi-ficant (p < O. 05). It is important to note that the great majority of the larvae injected ir.to the peritoneal cavity remained there developing to adult but stunted schistosomes. The worms recovered from the peritoneal cavity were considerably smaller than those found in the hepatic-portal system and have no hematin in the intestinal ceca, indicating that they. had not fed on blood (MOORE & MELENEY 5 ) • The oogram was normal in ali mice with exception of 3 animais (no eggs in intestinal fragments) injected with schis-tosomula by the intraperitoneal route. With this route, the ratio male: female schistoso-mes was very high. Our data show that schis-tosomula recovered from the skin are able to infect mice through the conventional routes of infection except the skin. This agree with the data reported by PEREIRA 9 , PEREIRA et al. 10 , and, in part, with those of STIREW ALT & UY 12 • As can be seen in Table II, a high mean of worm recovery was observed ( 32. 4 + 10. 5) in mice injected intravenously with schistosomula ( 4-day-old larvae) recovered from the Jung. The oogram was normal in ali animais. The percentage of recovery was 64.8. RESUMO I nfectividade, para o camundongo, de esquis-tossômulos ( Schistosoma mansoni) obtidos da pele e pulmão de camundongos infectados Esquistossômulos (Schistosoma mansoni 1 foram obtidos expondo-se a pele do abdomen de camundongos a cerca de 3.000 cercárias. Após 30 minutos a pele exposta foi removida e cortada em pequenos fragmentos, em sali-na. Três grupos de. 10 camundongos foram injetados com esquistossômulos (50 larva~ ::r: 1'ABLE i o C1) t-< Inf.ective capacity of schistosomula ( % of worm recovery as adult worms) collected from p. :,. H, z the skin and injected into mice. The animals were sacrificed í weeks after infection ..., ti o :,. s -r+ '-< Routes o f infection 1 ::,-· (!) l.l "'. Subcutaneous Intraperitoneal Intravenous ê- ~ p, 'ü :::, trl p. t-< Mice p ô 'i' T Mice p ô 'i' T Mice p d• 'i' T 1 r; ~ (!) o - ;d <= e-< :::, z 1 4 7 3 18 11 - 3 2 5+ 21 2 4 8 1 i)Q ·º Z, '-< 2 2 2 1 í 12 2 6 3 13 22 4 1 0 ã1 ,ro 3 1 7 2 11 13 4 11 2 21 23 2 1 1 G 1 ~~ p. H, (!) 4 5 3 4 17 14 2 6 10 24 2 2 1 7 s ~ i - ~- <· (!) ~-1 r+ 5 3 6 5 17 15 2 12 7 23+ 25 2 6 10 '< ?:1 Z, 2 10+ 5 rn (\l 6 1 2 1 5 16 1 6 26 5 4 ""' • r., ~ 2'. 7 2 6 2 12 17 4 12 5 25 27 2 3 1 8 ""' e, r+ .,.,. o"' 3 19 18 12 28 2 5 6 15 1 õs:º 8 8 5 2 6 2 (\l s R, <= . pi' 9 2 3 - 7 19 1 8 3 13 29 1 5 3 10 .,.,. .., ~ o vo ' '>3 e, 10 3 3 5 14 20 4 4 2 14 30 2 1 1 G ;::,, C'1 r,;· ::,, .,.,. o o e, 'i:Iº i::, ;l :;:! i::, Total 26 47 38 127 22 74 28 146 24 33 17 98 ã ;l 1-' i::, Mean & s.e. 2.6 4.7 3.8 12.7±4.7 2.2 7.4 2.8 14.G±6.1 2.4 3.3 1.7 9.8±3.8 o, " ~&, t,-:, s Recovery ( % ) 25.4 29.2 19.6 -.J ~ ' ~-... ~ e,.,..., J-L ~ P = Pairs T = Total + = No S. nwnson.i eggs in the liver an<l intestin-e s.e. = stan<lar<l error 1-' o <D < f-' -.J (!) "' ~7 e.o ' HOLANDA, J. C. & PELLEGRINO, J. - Infectivity of schistosomula (Schistosoma mansoni) recover-ed from the skin and lhe lung_ of infected mice. Rev. Inst. Med. trop. São Paulo 16:127-131, 1974. TABLE II V\Torm recovery from mice, 7 weeks after infection, by the intravenous route, with 50 schistosomula obtained from the lung of infected mice Mice 1 2 3 4 5 6 .7 8 9 10 Total Mean & s.e. Recovery ( % ) Pairs 18 19 4 10 15 7 3 8 7 13 104 10.4 6 5 7 3 9 10 5 9 10 6 70 7.0 'i' 2 4 4 4 5 4 2 9 7 5 46 4.6 Total 44 47 19 27 44 28 13 34 31 37 324 32.4±10.5 64.8 s.e. standard errar por animal), pelas vias subcutâneas, intra-peritoneal e endovenosa. As percentages de vermes adultos recuperados foram de 25,4,, 29,2 e 19,6, respectivamente. Esquistossômulos obtidos do pulmão de ca-mundongos infectados ( 4, dias depois da ex-posição a 3.000 cercárias) foram injetados por via endovenosa (50 larvas por animal) em 10 camundongos. A percentagem de re-cuperação de vermes adultos foi de 64,8. REFERENCES 1. BRENER, Z. - Esquistossomose experimen-tal. Rev. Brasil. Malariol. Doenças Trop. 11:473-506, 1959. 2. CLEGG, J. A. - "In vitrÔ" cultivation of Schistosoma mansoni. Exp. Parasitol. 16: 133-147, 1965. 3. CLEGG, J. A. & SMITHERS, S. R. - Death of schistosome cercariae during penetration 130 of the skin. II - Penetration of mamma-lian skin by Schistosoma mansoni. Parasitol. 58:111-128, 1968. 4. HOLANDA, J. C. ; PELLEGRINO, J. & GAZZINELLI, G. - Infection of mice with cercariae and schistosomula of Schistosomci mansoni by _intravenous and subcutaneous routes. Rev. Inst. Med. trop. São Paulo 16: 132-134, 1974. 5. MOORE, D. V. & MELENEY, H. E. Development of Schistosoma mansoni in the peritoneal cavity of mice. J. Parasitol. n: 235-245, 1955. 6. MOREIRA, C.; PEREIRA, L. H.; ARAúJO, e. e. & PELLEGRINO, J. - Attempts to infect hamsters through the cheek pouch and skin using schistosomula (Bchistosom.a mansoni). Trans. Royal Soe. Trop. Mecl. &: Hyg. 67:308, 1973. 7. PELLEGRINO, J. & FARIA, J. - The oogram method for the screening of drugs in Schistosomiasis mansoni. Amer. J. Trop. Med. &: Hyg. 14:363-369, 1965. HOLANDA, J. C. & PELLEGRINO, J. - Infectivity of schistosomula (Sch·istosoma mansoni) recdver-ed from the skin and the lung of infected mice. Rev. Inst. Med. trop. Seio Paulo 16:127-131, 1974. 8. PELLEGRINO, J. & SIQUEIRA, A. F. -Técnica de perfusão para colheita de Schis-tosoma mansoni em cobaias exp-erimental-mente infestadas. Rev. Brasil. Malariol. 8: 589-597, 1956 . 9. PEREIRA, L. H. - Capacidade ele migra-çcio das larvas de Schistosoma mansoni Sam-bon, 1907, no camundongo albino. Thesis. Institute of Biological Sciences, Federal Uni-versity of Minas Gerais, 1971, 38 pp. 10. PEREIRA, L. H.; COELHO, P. M. Z.; FONSECA, J. J. A. ; BREDT, A. & PELLE-GRINO, J. Migratfon of Schistosorna mansoni larvae in the albino mouse. Rev. Inst. Med. trop. Seio Paulo 14:306-309, 1972. 11. STIREWALT, M. A. - Cercaria vs. schis·-tosomule (S. mansoni): absence of the pe-ricercarial envelope in vivo i'lnd the early physiological and histological metamorpho-sis of the parasites. Exp. Parasitol. 13: 395-406, 1963. 12. STIREWALT, M. A. & UY, A. - Schisto-soma mansoni: cercárial penetration and schistosomule collection in an in vivo sys-tem. Exp. Parasitol. 26:17-28, 1969. Recebido para publicação · em 5/11/1973. 131 

Infectivity of schistosomula (Schistosoma mansoni) recovered from the skin and the lung of infected mice

https://www.revistas.usp.br/rimtsp/article/download/201079/185234

Infectividade, para o camundongo, de esquistossômulos ( Schistosoma mansoni) obtidos da pele e pulmão de camundongos infectados

Abstract

Similar works

Full text

Available Versions

Cadernos Espinosanos (E-Journal)