Comparison of various McCoy cell treatment procedures used for detection of Chlamydia trachomatis.

McCoy cells treated in six different ways, in addition to untreated cells, were compared to determine which gave rise to the largest number of Chlamydia trachomatis inclusions when tested with a laboratory-passaged strain. The same batch of cells was treated by irradiation, preinoculation exposure to cytochalasin B or 5-iodo-2'-deoxyuridine, and postinoculation exposure to cycloheximide, hydrocortisone, or emetine. Significantly more inclusions were always found in cells which had been treated with cycloheximide than in cells treated in any other way. Conversely, untreated McCoy cells always had significantly fewer inclusions than cells which had received some form of treatment. Similar results were obtained when cycloheximide-treated, irradiated, and untreated cells were inoculated with urethral specimens containing unpassaged organisms.