STUDY OF FLUORESCENT-ANTIBODIES DIRECTED AGAINST THE GUT EPITHELIUM OF SCHISTOSOMA-MANSONI .6. IMMUNOLOCALIZATION OF A CARBOHYDRATE EPITOPEAT THE DIFFERENT STAGE OF THE PARASITE EVOLUTION

In the course of previous works, we described on IgM monoclonal antibo dy directed to a carbohydrate epitope located on the gut epithelium su rface of the Schistosoma mansoni adult worm. We provided evidence that this epitope was present in all stages of the parasite and was partic ularly abundant in eggs. The current work was performed in order to sp ecify the epitope localisation, at each siege, by immunohistochemical techniques. The epitope appears to be located on the peripheral membra nes of the adult worm, while ii is produced by the alive miracidium in the eggs located in the tissues and subsequently spied out inside the periovular granuloma. Moreover, in adult worms, the observed structur e presents itself as a soluble form in organic solvents, on the other hand, in eggs, the epitope was essentially found made of an hydrosolub le substance. These datas can explain why, in experimentally infected mice, the epitope is mainly determined in urines at the sixth week oi infestation, when eggs are settled down in the tissues. Besides, the i nhibition of the monoclonal antibody fixation by a pentose which conta ins the Lewis X antigen, pointed out that the carbohydrate structure r ecognised by the monoclonal antibody could be the Lewis X antigen or a very closed structure.