Hydrophobic fraction of Taenia saginata metacestodes, rather than hydrophilic fraction, contains immunodominant markers for diagnosing human neurocysticercosis.
BACKGROUND
Considering that alternative antigens for diagnosing neurocysticercosis continue to be a challenge because of the increasing difficulty in obtaining parasites from naturally infected pigs for preparation of Taenia solium homologous antigen, the aim of the present study was to evaluate the detergent (D) and aqueous (A) fractions from saline extract of Taenia saginata metacestodes for diagnosing neurocysticercosis.


METHODS
Taenia saginata was obtained from naturally infected bovines in the Triângulo Mineiro region, State of Minas Gerais, Brazil. The carcasses came from cold storage units and had been slaughtered in accordance with the inspection technique recommended by the Federal Inspection Service. The D and A fractions were obtained by using Triton X-114 (TX-114). Serum samples were obtained from 40 patients with a diagnosis of neurocysticercosis, 45 with other parasitic diseases and 30 from apparently normal individuals. IgG antibody levels were evaluated using the ELISA and immunoblotting assays.


RESULTS
The ELISA sensitivity and specificity were 95% and 73.3%, when using saline extract; 95% and 82.6% for the D fraction; and 65% and 61.3% for the A fraction, respectively. The immunoblotting assay confirmed the ELISA results, such that the D fraction was more efficient than the other extracts, and the 70-68 kDa component was immunodominant among neurocysticercosis patients.


CONCLUSIONS
These results demonstrated that the D fraction from Taenia saginata metacestodes obtained using TX-114 can be used as a heterologous antigenic fraction in the immunoblotting assay for serologically diagnosing human neurocysticercosis, given its ability to select immunodominant antigens.
Gonçalves
Flávia de Assunção
Fde A
Department of Immunology, Microbiology and Parasitology, Institute of Biomedical Sciences, Federal University of Uberlândia, Uberlândia, MG, Brazil.
Machado
Gleyce Alves
GA
Oliveira
Heliana Batista
HB
Rezende
Maria Teresa Nunes Pacheco
MT
Mineo
José Roberto
JR
Costa-Cruz
Julia Maria
JM
D000818:Animals; D000947:Antigens, Helminth / Q000302:isolation & purification; D015415:Biomarkers; D016022:Case-Control Studies; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D006801:Humans; D015151:Immunoblotting; D007074:Immunoglobulin G / Q000097:blood; D020019:Neurocysticercosis / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D041202:Taenia saginata / Q000737:chemistry / Q000276:immunology*; D041201:Taenia solium / Q000276:immunology*
D000947:Antigens, Helminth; D015415:Biomarkers; D007074:Immunoglobulin G