Specific detection of circulating surface/secreted glycoproteins of viable cysticerci in Taenia saginata cysticercosis

Abstract

A mouse monoclonal antibody (MoAb), reactive with a repetitive carbohydrate epitope on lentil-lectin adherent glycoproteins present on the surface and in the secretions of Taenia saginata cysticerci, was used in the construction of a diagnostic ELISA assay to detect these glycoproteins in the serum of T. saginata infected cattle. The MoAb was used as the trapping layer and subsequently bound glycoprotein was revealed using the same MoAb and biotinylated peroxidase-streptavidin complex as the developing system. The assay was suitably specific. Exceptionally low background values were obtained with sera from animals with a range of commonly occurring tropical parasitic infections, including Taenia hydatigena, Echinococcus granulosus and Fasciola gigantica. The minimal detection level was approximately 200 live cysticerci in cattle. Parasite derived glycoprotein could be detected in serum from about 4-5 weeks post-infection onwards and was associated with a current infection, as drug treatment of infected cattle to kill the cysticerci resulted in the disappearance of these components from the circulation, while the titre of anti-parasite antibody remained high. The same assay also detected Taenia solium cysticercosis in humans.

Discrimination between active and inactive neurocysticercosis by metacestode excretory/secretory antigens of Taenia solium in an enzyme-linked immunosorbent assay.

“…Moreover, it has been reported that specific antibodies persist long after the parasite has been eliminated by immune mechanisms and/or drug therapy. 36,37 Although the number of CSF samples tested by immunoblotting was small, it is interesting to point out that a 45-kD antigen was recognized at a high frequency (86%). A good correlation was also found between high OD values and the number of antigens recognized by IgG antibody in the CSF samples.…”

The use of urban sewage sludge on pastures: the cysticercosis threat

“…However, most of these tests are not reliable because they do not differentiate between animals harbouring live metacestodes and animals in which only degenerate metacestodes are present, which are no longer infective. The development of a monoclonal antibody based antigen detection ELISA has allowed to identify those cattle harbouring living cysts [13,50]. This technique has been further improved by using monoclonal antibodies of the IgG isotype and by pretreatment of the serum by heat or trichloro-acetic acid in order to dissociate immune complexes.…”

Serological evidence for recent exposure to Taenia solium in Venezuelan Amerindians.

“…Cyst fluid, from T. solium cysticerci, was obtained as previously described, 15 and a surface-enriched antigen, N-octyl-␤-␦-glucopyranoside extract (NOG) of T. solium cysticerci and a cysticercus surface glycoproteins (GP) antigen were prepared accordingly to previously described methods. 16,17 Detection of circulating antigens secreted by viable parasites (Ag-ELISA). We performed Ag-ELISA with slight modifications from the original report.…”