CHLAMYDIA-PNEUMONIAE MULTIPLIES IN HUMAN ENDOTHELIAL-CELLS IN-VITRO

The ability of three C. pneumoniae isolates, Kajaani 6, Helsinki 12 an d TW-183, to grow in human umbilical vein endothelial cells (HUVEC) an d in an immortalized endothelial cell line EA.hy 926 was studied. All C. pneumoniae isolates were capable of multiplying in endothelial cell s. EA.hy 926 cells could support the growth of C. pneumoniae better th an HUVEC, yet less efficiently than HL and HEp-2 cells that are conven tionally used in C. pneumoniae culturing. Although centrifugation of t he inoculum greatly increased the inclusion yields, it was not necessa ry for infectivity. In addition, a persistent infection of C. pneumoni ae in EA.hy 926 and HL cells ensued and it was followed up for two mon ths. The fact that endothelial cells can serve as hosts to C. pneumoni ae might be a significant contributing factor in the pathogenesis of a therosclerosis, a disease which recent studies show to be associated w ith chronic C. pneumoniae infection.