Enzyme ImmunoAssay (ELISA) for the determination of IgM antibodies to Treponema pallidum (Tp) in human plasma and sera. The kit is intended for the follow-up of Tp-infected patients. For “in vitro” diagnostic use only.
Microplates are coated with Tp immunodominant synthetic antigens (recombinant p47, p17 and TmpA).In the 1st incubation, the solid phase is treated with diluted samples and anti-Tp IgM are captured, if present, by the antigens.
After washing out all the other components of the sample, in the 2nd incubation bound anti-Tp IgM are detected by the addition of anti hIgM antibody, labeled with peroxidase (HRP). The enzyme captured on the solid phase, acting on the substrate/chromogen mixture, generates an optical signal that is proportional to the amount of anti-Tp IgM antibodies present in the sample.
The presence of IgM in the sample may therefore be determined by means of a cut-off value able to discriminate between negative and positive samples.
Neutralization of IgG anti-Tp, carried out directly in the well, is performed in the assay in order to block interferences due to this class of antibodies in the determination of IgM.