Perturbations of the topography of the tegument of adult Schistosoma mansoni. A scanning electron microscope study.

1. Adult Schistosoma mansoni show a proclivity to release fragments of the tegumental surface membrane when they are incubated in various media, or after they are exposed to positively charged microspheres. Scanning electron microscopy was used to examine the extent and nature of the perturbations induced by the two treatments used to prepare tegumental membranes. 2. Incubation of the parasites in a phosphate-buffered medium resulted in extensive blebbing and release of vesicles from the tegument. 3. Attachment of positively charged microspheres followed by their release yielded tegument membrane fragments of a different morphology. 4. The nature and implications of these perturbations to membrane processes occurring at the tegument of schistosomes are discussed.