Immunological responses to antigen B from Echinococcus granulosus cyst fluid in hydatid patients.
The immunological reactivity of Echinococcus granulosus antigen B was evaluated in 30 hydatid patients. Antigen B was purified from sheep hydatid cyst fluid by electroelution from a non-reducing SDS-PAGE gel (AgB). In ELISA and immunoblotting (IB), determining antibody production in sera from patients with hydatid disease and with other parasitic infections, purified AgB showed higher specificity than a partially purified antigen named pH5PPT (100% vs 83% in pH5PPT-ELISA and 58% in pH5PPT-IB). AgB-IB achieved higher sensitivity than AgB-ELISA (80% vs 63%). All AgB-IB positive sera recognized the 12 kDa subunit. Qualitative AgB-IB assessment of IgG isotype responses identified IgG4 as the predominant isotype (87%). The other isotypes showed a lower percentage of positive reactions: IgG1, 33%; IgG2, 21%; and IgG3, 17%. PBMC proliferative assay revealed a cellular response to AgB in 100% of patients' PBMC. These findings confirm antigen B, especially its smallest subunit, as a good diagnostic molecule.
Ioppolo
S
S
Laboratorio di Immunologia, Istituto Superiore di Saniti, Roma, Italy.
Notargiacomo
S
S
Profumo
E
E
Franchi
C
C
Ortona
E
E
Rigano
R
R
Siracusano
A
A
D000818:Animals; D000909:Antibodies, Helminth / Q000097:blood; D000918:Antibody Specificity; D000947:Antigens, Helminth / Q000737:chemistry; D004443:Echinococcosis / Q000175:diagnosis / Q000276:immunology*; D004446:Echinococcus / Q000276:immunology*; D015801:Helminth Proteins; D006801:Humans; D007120:Immunochemistry; D007074:Immunoglobulin G / Q000097:blood / Q000145:classification; D066298:In Vitro Techniques; D008074:Lipoproteins / Q000737:chemistry / Q000276:immunology*; D008213:Lymphocyte Activation; D012698:Serologic Tests; D012756:Sheep
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D015801:Helminth Proteins; D007074:Immunoglobulin G; D008074:Lipoproteins; C089273:antigen B, Echinococcus