Pelvic inflammatory disease in patients infected with Chlamydia trachomatis: in vitro cell mediated immune response to chlamydial antigens.

Blood samples were obtained from 11 women with laparoscopically confirmed acute salpingitis who yielded positive cultures of Chlamydia trachomatis from the cervix. Four patients also had perihepatitis. Lymphocyte transformation assays, using C trachomatis serovars I and L2 as antigens, showed that the patients' lymphocytes responded to antigenic stimulation more strongly than the lymphocytes of age matched controls. Responses to the I and L2 antigens correlated strongly, but greater responses were obtained to the L2 antigen. No correlation was found between the response in the lymphocyte transformation assay and the degree of the inflammatory changes of the fallopian tubes, the presence of perihepatitis, or the titres of humoral antibodies to C trachomatis as measured by microimmunofluorescence. Sequential transformation assays, however, showed that patients with perihepatitis tended to have a more sustained response.