Cytochemical localization of carbohydrate residues in microfilariae of Wuchereria bancrofti and Brugia malayi.

We investigated the localization of carbohydrate residues on the surface structures of microfilariae of Wuchereria bancrofti and Brugia malayi, using a panel of 10 different gold-labeled lectins and chitinase. The sheath, a structure that encloses the microfilariae, is not a homogeneous structure, presenting two clearly distinct layers. The outer layer is more electron dense and was not labeled with the lectins. The inner layer is less dense and was intensely labeled with lectins, especially those that recognize D-galactose and N-acetyl-D-galactosamine. Small differences were observed in the lectin labeling pattern of microfilariae of W. bancrofti and B. malayi. D-galactose and fucose were observed in the cuticle of both species. Chitin, as revealed with gold-labeled chitinase, was observed in the cuticle of microfilariae of W. bancrofti but not in B. malayi.