Comparisons between scolex and membrane antigens of Cysticercus fasciolaris and Cysticercus cellulosae larvae for immunodiagnosis of neurocysticercosis.

Abstract

The antigen source for enzyme-linked immunosorbent assay (ELISA) and enzyme-linked immunotransfer blot for neurocysticercosis is generally Taenia solium. A comparison of the membrane and scolex extracts of Cysticercus cellulosae and Cysticercus fasciolaris (larval stage of Taenia taeniaeformis) for the immunodiagnosis of neurocysticercosis has been performed. C. fasciolaris cysts were produced experimentally in rat liver. C. cellulosae was obtained from muscle of infected pigs. The antigen extracts of membrane and scolex were compared using ELISA in 50 patients and 50 control participants to detect immunoglobulin (Ig) G or IgM antibodies. Proteins separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis were immunoprobed using pooled and individual sera. The gold standard for diagnosis was visualization of scolex in ring lesions by magnetic resonance imaging or computed tomography scans. ELISA for IgG antibodies using C. fasciolaris membrane had the highest sensitivity of 94%. Specificity ranged from 78% to 90%. Immunoreactive bands common to all 4 antigens were seen between 60 and 70 kDa and 40 and 45 kDa. The presence of comparative antigenic bands between human and rat pathogens provides convincing evidence for use of C. fasciolaris antigens for immunodiagnostic procedures. The antigen can be produced in small animals in standardized laboratory conditions within 60 days.