Detection of IgM antibodies directed against the gut-associated circulating cathodic antigen in sera from Schistosoma mansoni infected patients. Development and comparison of three enzyme-linked immunoassays.
The majority of the human IgM antibodies detected with an immunofluorescence assay (IFA) on adult worms are directed against the gut-associated circulating cathodic antigen (CCA). In order to study this phenomenon further we developed and evaluated three related ELISA methods to specifically detect IgM antibodies against purified CCA. The assays employed: 1) direct coating of CCA, 2) indirect coating of CCA via a monoclonal antibody, and 3) IgM antibody-capture by rabbit anti-mu chain antibodies. Using a group of 46 positive sera, it was found that the three ELISA's and the IFA were significantly correlated. To discriminate between positive and negative sera we used a cut-off level of average reactivity + 3 standard deviations of 50 negative sera. False negative reactions were not found in any of the ELISA's, while both in the direct and indirect ELISA one false positive reaction occurred. For further studies or diagnostic use the antibody-capture ELISA is recommended.
van Dam
G J
GJ
Laboratory of Parasitology, University of Leiden, The Netherlands.
Qian
Z L
ZL
Fillié
Y E
YE
Rotmans
J P
JP
Deelder
A M
AM
D000818:Animals; D000909:Antibodies, Helminth / Q000302:isolation & purification*; D000947:Antigens, Helminth / Q000097:blood* / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005455:Fluorescent Antibody Technique; D006801:Humans; D007075:Immunoglobulin M / Q000276:immunology / Q000302:isolation & purification*; D012550:Schistosoma mansoni / Q000276:immunology*; D012555:Schistosomiasis mansoni / Q000276:immunology
D000909:Antibodies, Helminth; D000947:Antigens, Helminth; D007075:Immunoglobulin M