A Study for Culture Condition of Chlamydia pneumoniae / 대한임상병리학회지

ABSTRACT

BACKGROUND: Chlamydia pneumoniae, a new species of the obligate intracellular Chlamydia, has been recognized as a significant pathogen that causes infection of the human respiratory tract and has recently been associated with coronary atherosclerosis. Diagnosis of infections with C. pneumoniae is problematic, because the syndrome usually presents few distinguishing features and culture of the organism is far more difficult than other Chlamydia species. To further improve the cell culture isolation and passage of C. pneumoniae organisms. we have studied several chemical and physical factors that might affect their viability and growth. METHODS: C. pneumoniae strain (TW-183) was obtained from the Centers for Disease Control, Atlanta. Ga. First we compared McCoy HeLa-229, and HEp-2 cells in the search for a more efficient and practical cell culture system. The growth rate of C. pneumoniae was assessed by the effects of diethylaminoethyl-dextrin, by the adequate centrifugation force and time, by the growth promoting effect of cycloheximide, and by the optimal incubation time. All of the results were evaluated by the indirect immunofluorescent stain using the genus-specific monoclonal antibody(HYMo 1-1) to Chlamydia. RESULTS: The HEp-2 cell was the most efficient for culturing C. pneumoniae and the inclusion bodies in monolayer were increased with DEAE-dextran pretreatment at 30microgram/ml. Also application of a centrifugal force of 1.500 xg for at least 15 minute during inoculation enhanced the growth of C. pneumoniae. The best concentration of cycloheximide in the culture medium for host cell cytostasis was 1microgram/ml. The yields of organisms were greater when the cultures were harvested at 48 hours. CONCLUSIONS: We suggest that this system may make it more practical for laboratories to culture for C. pneumoniae.