Silver enhancement of lectin-gold and enzyme-gold cytochemical labelling of eggs of the nematode Onchocerca gibsoni.

Wheat germ agglutinin-gold and chitinase-gold complexes were used to demonstrate the presence of chitin on the surfaces of eggs of the animal parasitic nematode Onchocerca gibsoni. The gold complexes were enhanced by silver intensification and examined by light microscopy (LM), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Distinctive labelling of the egg surfaces was obtained with both probes in all three microscope modes. The results indicate that the small colloidal gold markers (3-10 nm) commonly used for high resolution TEM studies may be silver enhanced and also used for sensitive LM and SEM studies.