LYMPHOCYTE-RESPONSES TO CHLAMYDIA ANTIGENS IN PATIENTS WITH CORONARY HEART-DISEASE

Aims To clarify the relationship of Chlamydia pneumoniae infection and coronary atherosclerosis we studied cell-mediated and humoral immune responses to Chlamydia in 93 patients with angiographically confirmed coronary heart disease and in 115 controls without angiographically de monstrable lesions. Methods and results Cell-mediated responses were a nalysed by measuring lymphocyte proliferative reactivity to whole elem entary body antigens of C. pneumoniae. Control antigens included C. tr achomatis and purified protein derivative of tuberculin. Chlamydia-spe cific antibodies were measured using microimmunofluorescence assay. Ma rked C. pneumoniae-specific immune reactivity, demonstrated by the hig h incidence of elevated IgG and IgA antibodies and strong lymphocyte p roliferative response, was associated with coronary heart disease in m ale but not in female patients or controls. In male patients, the cell -mediated responses were strong to C. pneumoniae (median stimulation i ndex 9,6) and to C. trachomatis (stimulation index 6,9). The females w ith coronary heart disease showed significantly stronger cell-mediated responses to C. pneumoniae (stimulation index 6,5) than to C. trachom atis (3,8; P<0.001) and were comparable to the controls. Conclusion Ma rked cell-mediated and humoral immunity to C. pneumoniae in males with coronary heart disease suggest that the immune mechanisms triggered b y Chlamydia are a possible contributing factor in the disease pathogen esis of coronary atherosclerosis in males. The Chlamydia-specific cell -mediated responses seem to be predominantly induced by antigenic stru ctures that are similar among different Chlamydia-species.