Echinococcus granulosus: The distribution of hydatid fluid antigens in the tissues of the larval stage : II. Localization of the thermostable lipoprotein of parasitic origin (antigen B)

By means of a rabbit monospecific antiserum, the localization of hydatid fluid antigen B, a thermostable lipoprotein was demonstrated in the larval tissues of Echinococcus granulosus. The antigen was present in the cuticular “membrane,” in the tegument of the protoscoleces, and in the substance contained inside the brood capsules. This distribution corresponds exactly to that of PAS-positive substances described previously in the hydatid cyst of E. granulosus. The localization of antigen B and the fact that it was not detected in the excretory system suggest that the sub-tegumental cells participate in its secretion.