I too like Andrew work for a diagnostic company. Right now we do not sell
any chlamydia products, but are looking into these products. In the past I
have been involved with development of chlamydia antigen detection products
and have also developed, but never commercialized an antibody test.
It is my understanding that an acute genital infection can be diagnosed by
most methods, but required detection in the localized region. Antibody is
present in the genital secretions as well as antigen and DNA/RNA. The
difficult part about detection of localized antibody is specificity and my
company is looking into such a product (very early work only).
As far as chronic infections, the most predominant form is pelvic
inflammatory diseases (PID) and I think most agree that this disease, when
associated with chlamydia, is caused by antibody. In fact, I think many
believe the antibody causing disease is against heat shock protein. The
problem again is assay specificity.
I know little about chlamydia pneumoniae, but do know that the immune
responses appear to differ from C. trachomatis.
I hope this helps a little.