Efficacy of various cell culture procedures for detection of Chlamydia trachomatis and applicability to diagnosis of pediatric infections

Abstract

In this study, 5-iodo-2'-deoxyuridine-, cytochalasin B-, and cycloheximide-treated and untreated McCoy cells were inoculated with representative strains of Chlamydia trachomatis serotypes, as well as with clinical specimens from a pediatric population, and the quality and quantity of the cytoplasmic inclusions were examined. Cycloheximide treatment consistently rendered the highest number of quality inclusions per milliliter of any method tested for both the laboratory strains (P less than 0.001) and the clinical isolates (P less than 0.01). The inclusion counts in untreated McCoy cells were either higher than or not significantly different from those in 5-iodo-2'-deoxyuridine- an cytochalasin B-treated cells. However, the quality of the inclusions, using the criteria of size, brightness, and ease of detection produced in untreated and 5-iodo-2'-deoxyuridine-treated cells, was inferior to the quality of those obtained by other procedures. Cells treated with cytochalasin B had the best-quality inclusions as compared with those treated by any other method. It is recommended from our experience that for overall sensitivity and simplicity cycloheximide treatment is the method of choice for isolation of C. trachomatis in McCoy cells.

Comparison of HeLa 229 and McCoy cell cultures for detection of Chlamydia trachomatis in clinical specimens

“…The diagnosis of a C. trachomatis infection, e.g., urethritis or cervicitis, is primarily dependent upon isolation by cell culture procedures. McCoy cells and HeLa 229 cells are commonly used, and various cell treatments have been described to enhance the sensitivity of the assay (1)(2)(3)(4)(5)(6)(7)(8)(9)11). Most authors used one cell type and one or more laboratory strains.…”

“…However, these strains have had different histories of laboratory passage. The investigators studying the impact of modifications on the isolation rate in clinical specimens (1,2,5,6,9,11) always used one type of cell culture.…”

“…Cycloheximide treatment has been used extensively for the isolation of C. trachomatis in McCoy cells. The antibiotic was always added to the growth medium after centrifugation (2,3,5,6,8,9,11) of the specimen onto the monolayer. Also, pretreatment of the cell monolayer with this compound has been included in cell culture methods.…”

Infectivity of Chlamydia trachomatis in tissue culture with newborn calf serum

“…McCoy cells were maintained routinely in our laboratory for no more than 35 passes after their removal from liquid nitrogen storage. Growth medium used for the replication of the McCoy cells was previously described (9). This medium routinely contained 10%o heat-inactivat-ed FBS.…”

“…Preparation, maintenance, and treatment of the McCoy cells with cycloheximide have been previously described (9).…”