Recovery ofChlamydia trachomatis by inoculation of McCoy cell suspensions

Growth of two laboratory strains ofChlamydia trachomatis (Gambia 17 and UW 5) was compared in McCoy cell monolayers 1–3 days old and McCoy cells inoculated while in suspension (day 0). Both cell preparations were treated with cytochalasin B. Each chlamydial strain produced more inclusions in the cell suspension preparations than in monolayers. Efforts to inoculate cycloheximide-treated cells in suspension were unsuccessful because of the toxic effect of this chemical. When patient specimens were tested in cell suspensions and in monolayers, all positives were detected comparably in both systems, although bacterial contamination was more pronounced in the cell suspensions. The results indicate that cell suspensions can be used as a convenient and rapid supplement to preformed monolayers for chlamydial culture tests.