Isolation of chlamydiae in untreated and Cytochalasin B treated McCoy cells.

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.

Section: Resultsmentioning

confidence: 99%

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

Evans¹,

Taylor‐Robinson²

1979

“…Most methods of chlamydial isolation and cultivation in cell culture involve treatment of the host cells with agents that prevent their multiplication (16). Replicating cells have been favored by some because of potential risks of handling some of the agents used to inhibit replication and for reasons of technical convenience (5,9,15). Many comparative investigations have shown that treated cells contain more inclusions than untreated cells (3,6,7,14,16,19).…”

Section: Discussionmentioning

confidence: 99%

Comparison of methods for cultivation and isolation of Chlamydia trachomatis

Benes¹,

McCormack²

1982

McCoy cells treated with cycloheximide, iododeoxyuridine, and DEAE-dextran and untreated McCoy cells were inoculated with two stock strains of Chlamydia trachomatis and with 231 urethral specimens from men, 53 (23%) of which contained C. trachomatis. Isolation rates, number and quality of inclusions, and quality of the cell monolayers were compared. There were no significant differences between the isolation rates in the four systems, although the most isolations were made in the untreated and cycloheximide-treated cells. Cycloheximide-treated cells produced, from both the clinical specimens and the two stock strains, significantly more inclusions than any of the other systems. The monolayer of the cycloheximide-treated cells and the inclusions that grew in these cells were optimal for examination and detection of C. trachomatis.

“…The basis for evaluating these methods was prompted by limited information and contradictory results (2,3,(8)(9)(10)12). Cells treated by irradiation, IUdR, cytochalasin B, and cycloheximide have been reported to be more sensitive than untreated McCoy cells (3,5,11,16).…”

Section: Discussionmentioning

confidence: 99%

“…Cells treated by irradiation, IUdR, cytochalasin B, and cycloheximide have been reported to be more sensitive than untreated McCoy cells (3,5,11,16). In contrast, other workers indicate that untreated cells are as sensitive as treated cells and that pretreatment of cells, expensive equipment, or hazardous chemicals as with irradiation, IUdR, and cytochalasin B are not necessary (2,(8)(9)(10)).…”

Section: Discussionmentioning

confidence: 99%

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

Scolea¹,

Keddell²

1981

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.