Fine structure and cytochemical evidence for the presence of polysaccharide surface coat of Dirofilaria immitis microfilariae

Cherian P. V., Stromberg B. E., Weiner D. J. and Soulsby E. J. L. 1980. Fine structure and cytochemical evidence for the presence of polysaccharide surface coat of Dirofilaria immitis microfilariae. International Journal for Parasitology10: 227–233. Cytochemical staining techniques were employed at the fine structural level using ruthenium red, ruthenium violet and Alcian blue-lanthanum nitrate to demonstrate the polysaccharide rich surface coat of Dirofilaria immitis microfilariae. The coat matrix present at the external surface of the cuticle of microfilariae stained densely with each of the polycationic dyes. The reaction products were restricted to the outer surface of the cuticle suggesting that the polycationic dyes did not penetrate the cuticle. The junctions of the cuticular annulations lacked surface coat matrix and reaction products which might be indicative of the absence of carbohydrate residues or the masking of reactive sugar molecules in these areas. The speciflcity of the reaction was indicated by the absence of reaction products in untreated organisms. These carbohydrate moieties probably represent glycoproteins as structural constituents of the parasite surface. Ultrastructural analysis of the surface of microfilariae is of signiflcance in elucidating both the molecular dynamics of the parasite surface and its immunological function in the host.     

ISOLATION AND CHARACTERIZATION OF GLYCOSAMINOGLYCANS IN BRAIN OF DIFFERENT SPECIES

Abstract— The uronic acid-containing glycosaminoglycans present in the brains of rat, monkey, chicken, sheep and rabbit were isolated into various fractions by combining the cetyl pyridinium procedure and DEAE-Sephadex column chromatography. The analyses of the fractions show that hyaluronic acid, chondroitin-4-sulphate, chondroitin-6-sulphate, heparan sulphate and a testicular hyaluronidase-resistant galactosamine-containing GAG are present in the brain of all the species studied. Hyaluronic acid is the major GAG (33–41 per cent). Chondroitin-4-sulphate (19–35 per cent), and heparan sulphate (11–19 per cent), are the next prominent GAGs, in all the species except chicken. The results indicate the similarity in the pattern of GAGs in the brain of all the species.