Electron microscopical studies of Strongyloides ratti infective larvae: loss of the surface coat during skin penetration.
Previous indications using radiolabelled larvae that Strongyloides ratti free-living infective larvae lose a surface coat during penetration of the skin were further investigated by transmission electron microscopy of the cuticle of S. ratti infective larvae in the free-living stage, after penetration of mouse skin, and after migration to the lungs. These studies demonstrated the presence of a faint electron-dense surface coat external to the epicuticle on free-living worms which was absent from larvae recovered from the skin and lungs. When free-living infective larvae were incubated in 10% CO2 at 37 C and then examined with phase-contrast microscopy, worms were observed in the process of losing this coat. These observations confirm the hypothesis that S. ratti infective larvae lose a surface coat during penetration of the skin.
Grove
D I
DI
Department of Medicine, University of Western Australia, Queen Elizabeth II Medical Centre, Nedlands.
Warton
A
A
Northern
C
C
Papadimitriou
J M
JM
D000818:Animals; D005260:Female; D051379:Mice; D008810:Mice, Inbred C57BL; D008854:Microscopy, Electron; D051381:Rats; D011919:Rats, Inbred Strains; D012867:Skin / Q000469:parasitology; D013321:Strongyloides / Q000502:physiology / Q000648:ultrastructure*; D013322:Strongyloidiasis / Q000469:parasitology*