Isolation of TRIC agent (Chlamydia) in irradiated McCoy cell culture from endemic trachoma in field studies in Iran. Comparison with other laboratory tests for detection of Chlamydia.

Abstract

(I967), has been used to recover laboratory-adapted isolates of TRIC agent from the infected eyes of simians (Gordon and others, I963) and of man (Magruder and others, I963).Studies recently completed in this laboratory on clinical specimens from genital or genitally-related ocular infections in London showed that isolation in irradiated McCoy cells is more sensitive for the detection and isolation of chlamydial agents than cultivation in the yolk sac of embryonated hen's eggs or inclusion-finding in Giemsa-stained scrapings (Gordon, Harper, Quan, Treharne, Dwyer, and Garland, I969; Dunlop, Hare, Darougar, Jones, and Rice, I969). It was also shown that TRIC agent could be isolated in the cell culture system from endemic trachoma in Iran, but the number of specimens tested was too small to give an assessment of the sensitivities of the two methods of isolation in relation to the finding of inclusions in conjunctival scrapings.Isolates of TRIC agent from endemic trachoma in the Middle East and the Far East have shown biological differences from TRIC isolates of genital origin in London, USA, and Taiwan (Alexander, Wang, and Grayston, I967; McComb and Bell, I967; Wang and Grayston, I970, 197!). It was, therefore, not clear whether the irradiated McCoy cell system could provide a satisfactory alternative to the yolk sac of embryonated hen's eggs for isolation of TRIC agent from endemic trachoma.This paper compares the results of isolation of TRIC agent in cell culture with those of isolation in the yolk sac of embryonated eggs from scrapings collected during a field study of trachoma in certain villages in Iran. It also relates these isolations to the findings of inclusions in conjunctival scrapings stained by iodine or Giemsa stain, and the results of microimmunofluorescence typing of the isolates.

Antichlamydial antibody in tears and sera, and serotypes of Chlamydia trachomatis isolated from schoolchildren in Southern Tunisia.

“…McComb and Nichols (1970) showed by a complex cross-absorption technique that antibody in eye secretions faithfully reflected the type of TRIC agent infecting the eye. Studies in our laboratory (Darougar et al, 1971b;Treharne et al, 1971;Treharne et al, 1972;Jones, 1974) have shown, in agreement with the work of others (Wang and Grayston, 1970;Wang and Grayston, 1974), that TRIC agent serotypes A, B, and C are mainly responsible for ocular infection in hyperendemic trachoma areas.…”

“…Methods of ocular examination, assessmenit of the intensity of conjunctival inflammatory disease in trachoma, and methods of collection of specimens for the isolation of C. trachomatis are reported elsewhere (Darougar et al, 1971a;Darougar and Jones, 1971;Darougar et al, 1971b;Dawson et al, 1975). SEROTYPING Isolates from cell culture were inoculated into yolk sacs of developing chick embryos to produce antigen for use in the micro-IF test (Treharne et al, 1973).…”

Detection of Chlamydia trachomatis in Clinical Specimens by Nucleic Acid

“…Definitive diagnosis of chlamydial infections is usually made by isolation of infectious organisms in cell culture (Darougar et al, 1971) or by direct demonstration of specific antigens in inflammatory exudates using monoclonal antibody staining (Tam et al, 1984). Both methods, although specific and sensitive, need microscopy for evaluation of test results and are therefore time consuming and require a trained specialist.…”

Sensitivity of immunoperoxidase and immunofluorescence staining for detecting chlamydia in conjunctival scrapings and in cell culture.

“…Received for publication 26 January 1978 COLLECTION AND STORAGE OF SPECIMENS Conjunctival scrapings The conjunctivae of cats were anaesthetised with three to four drops of Jocaine (Darougar et al, 1971b). Conjunctival scrapings were collected using sterile aluminium scrapers, which were flattened at both ends.…”