Ultrastructural localization of the circulating anodic antigen in the digestive tract of Schistosoma mansoni using monoclonal antibodies in an immunogold labeling procedure
de Water, R.; Fransen, J.A.; Deelder, A.M.
American Journal of Tropical Medicine and Hygiene 35(3): 549-558
1986
ISSN/ISBN: 0002-9637 PMID: 3518506 Document Number: 278652
The presence of the circulating anodic antigen (CAA) in the digestive tract of various life cycle stages of S. mansoni was determined by an indirect gold-labelling procedure using CAA specific monoclonal antibodies. In cercariae, gold label was found in the cytoplasm and in the surface coat of the gut epithelium. A few gold particles were found in the luminal surface coat of the oesophagus epithelium, located proximally to the gut. In 3.5-week-old worms and adult male and female worms, CAA was present in the Golgi apparatus, in cytoplasmic vesicles and in the surface coat of the gut epithelium. CAA-positive lysosome-like bodies were only encountered in the most caudal quarter of the gut. In the gut lumen, CAA was associated with host white blood cells and with a thick layer of finely granular, moderately electron-dense material covering the gut epithelium: the oesophagus did not show CAA reactivity. These results prove that CAA is a gut-specific antigen produced by various life cycle stages of S. mansoni from the cercarial stage on.