FIG. 4.

Immunoreactivity of T. pallidum proteins separated by IEF (pH 5 to 7) 2DGE with human sera. T. pallidum lysates were separated by IEF at pH 5 to 7 in the first dimension, followed by 8 to 20% SDS-PAGE in the second dimension. Gels were subsequently silver stained (A) or immunoblotted with a 1:500 dilution of pooled human sera from healthy blood donors (B), primary-syphilis patients (C), secondary-syphilis patients (D), early-latent-syphilis patients (E) or late-latent-syphilis patients (F). Black boxed areas indicate major polypeptides that were reactive with each serum pool. Acidic and basic ends are denoted, and relative molecular mass markers (in kilodaltons) are indicated to the left of each gel.