Production of Chlamydia trachomatis antigen and antiserum: a review

In this review of the production of Chlamydia trachomatis antigen, a procedure is described in which Chlamydia-infected cells are harvested from culture cells by mechanical disruption 48 to 72 h after infection. Released elementary bodies (EB) are purified by differential centrifugation, followed by centrifugation through Renografin gradient. The purified, formalinized EBs are suitable for use in such serological tests as microimmunofluorescence (MIF) or radioimmunoassay (RIA). The reticulate body (RB) stage of the chlamydiae are harvested from infected cells 27 to 28 h postinfection; when formalinized, these are useful as a serological screening antigen. Chlamydial inclusions in infected cells may be used as a single antigen in screening serology. Type-specific antisera may be produced in mice. Broadly reactive antisera are produced by immunization of guinea pigs or rabbits with multiple C. trachomatis serotypes. Among the potential applications for such hyperimmune sera are the staining of inclusion-containing cells and the direct demonstration of chlamydial antigen by solid-phase RIA.