Class specific immunoglobulin response to individual polypeptides of Chlamydia trachomatis, elementary bodies, and reticulate bodies in patients with chlamydial infection.

Sera from 10 women with Chlamydia trachomatis culture positive cervicitis and sera from six men with C trachomatis positive non-gonococcal urethritis were studied for the presence of IgG, IgM, and IgA antibodies to polypeptides of C trachomatis elementary bodies and reticulate bodies using immunoblotting techniques. All the sera with IgG, IgM, or IgA immunoglobulins specific to C trachomatis recognised the major outer membrane protein (MOMP) of elementary bodies. IgG antibodies also detected several other proteins, whereas IgM immunoglobulins recognised only MOMP and proteins of 60 kD, 62 kD, and 66 kD. The IgA reacted with MOMP and the 60 kD and 62 kD proteins in elementary bodies. Class specific antibody response against the proteins of reticulate bodies was similar to that observed for elementary body antigens--with one substantial difference: no reaction was observed in the 60 kD and 62 kD positions. This suggests that 60 kD and 62 kD proteins are deficient in reticulate bodies.