Ultrastructural features of the tegument of adult Cynodiplostomum azimi (Trematoda:Digenea) in experimentally infected albino rats
Abo Shafey, A.; Khalil, A.I.; Seif, A.I.
Journal of the Egyptian Society of Parasitology 22(3): 709-718
1992
ISSN/ISBN: 1110-0583 PMID: 1431290 Document Number: 391763
The ultrastructure of the tegument of adult Cynodiplostomum azimi and the lesions caused by the worm at this host parasite interface in albino rats are described. The tegument consists of a syncytial distal cytoplasm (approx. 2.01-3.1 microns in thickness), bounded by an outer apical plasma membrane and an inner basal trilaminated lamina. The subtegumental cells (approx. 10.34 microns in length) are connected with the distal cytoplasm by means of cytoplasmic trabeculae. The morphology of the tegument appeared very variable. Large areas were formed of irregular folds, while other areas carried finger-like or papilla-form structures. Tegumental spines appear to have a crystalline lattice structure. Three morphologically distinct types of membrane-bound inclusion bodies were described in the tegumental/perikaryal complex. The electron-lucent elongate bodies (approx. 0.23 micron in length) were the predominant first type. The second was round-ovoid bodies (average length 0.12 micron) with a central core of electron-dense material. The third was electron-dense, rod-like in shape (0.28 micron in length) and occurred occasionally. The majority of these inclusion bodies were oriented parallel to the tegumental surface. The host's mucosa at the parasite interface showed marked flattening and partial to complete loss of mucosal microvilli. Inflammatory cells, particularly eosinophils were observed at the host-parasite interface.