The Propagation and Preservation of Eperythrozoon coccoides

Abstract

SUMMARY : The propagation of Epe ythroxoon coccoides in embryonated hen eggs inoculated by the yolk sac and intravenous routes is recorded. Fourteen continuous serial passages were made in the yolk sac and sixteen passages were made after intravenous inoculation into the chick embryo. The mortality among infected embryos was low; splenic enlargement was the only lesion detected. Once the strain had become established. E . coccoides was seen in blood smears taken from some eggs after each passage. Yolk sac or blood from infected embryos proved to be infective for mice on each occasion they were examined ; 10-6 dilutions of yolk sac were also infective. E. coccoides was preserved for short periods at -80" in mouse and chickembryo blood, but not in yolk sac. The organism was also preserved in mouse blood and chick-embryo tissues at -79'. The presence of 10% (v/v) sterile glycerol appeared to increase the stability of E. coccoides in chick-embryo tissues stored at -79'.No reports were found in the literature about the propagation of any species of eperythrozoa in the laboratory. The limited host range of this group of organisms has made their manipulation difficult and satisfactory methods of cultivation and preservation should afford an opportunity to extend our knowledge of them, This report records the successful propagation of Eperythrozoon COCcoides in embryonated eggs inoculated by the yolk sac and intravenous routes, and the preservation of this organism a t -30' and a t -79". METHODSThe strain of Epeythrozoon coccoides Schilling, 1928, used was obtained from mice at the Molten0 Institute, University of Cambridge, by courtesy of Dr June Thurston.Albino mice (c. 20 g.) from a strain infected with Epeqjthrozoon coccoides were used to examine the infectivity of the early passages in chick embryos inoculated by the intravenous route. The albino mice were splenectomiaed and blood smears taken from them for examination on three alternate days in each week for a 10 day period before inoculation, in order to detect carriers. Subsequently, VS mice (from the National Institute for Medical Research, Mill Hill, through the courtesy of Dr A. W. Gledhill) which are normally free from E. coccoides, were used for all experiments. Splenectomized VS mice (c. 15-2Og.) were used to examine the infectivity of the later intravenous passages, and for all the yolk-sac passages; they were also used in the early experiments with preserved materials. Intact VS mice were used for the later experiments with preserved materials and for the titrations. Each mouse received a standard

Review of clinical aspects, epidemiology and diagnosis of haemotropic Mycoplasma ovis in small ruminants: current status and future perspectives in tropics focusing on Malaysia

“…“Sheep kidney culture” and “mixed hamster kidney-bovine lymphatic tissue culture” media were both unsuccessful in cultivating M. ovis . However, Seamer ( 1959 ), successfully passaged Eperythrozoon coccoides 14 times by yolk sac inoculation and 16 times by intravenous injection of the chick embryo. Ershaduazzaman and Iskandar ( 2001 ), using embryonated chicken eggs, successfully passaged M. ovis through the yolk sac and maintained its attachment to the red blood cell in heparinised samples by incubation in Eagle’s medium supplemented with inosine and bovine foetal serum under 5% CO 2 .…”

Elimination ofEperythrozoon coccoidesinfection from mouse colonies

“…For these tests mice about 3 or 4 months old are most suitable since an infection rate representative of the colony will not have developed in very young mice and will be more difficult to demonstrate with increasing age. In this connexion the fact should be stressed that E. coccoides is readily transmissible to intact mice and that parasitaemia is easily demonstrable; indeed, we have utilized this characteristic of E. coccoides as the basis of much experimental work over many years (Niven et al 1952;Seamer, 1959). SUMMARY 1.…”

Phylogenetic analysis and description of Eperythrozoon coccoides, proposal to transfer to the genus Mycoplasma as Mycoplasma coccoides comb. nov. and Request for an Opinion

“…coccoides has not been cultivated on artificial media. Derrick et al (1954) found E. coccoides survived up to 9 days in embryonated chicken eggs but attempts at passage were unsuccessful; serial passages in embryonated chicken eggs have been reported (Seamer, 1959) but not confirmed. The standard procedure for determining whether a mouse colony was infected was to splenectomize a dozen 3-to 4-month-old mice and examine their blood daily (Gledhill et al, 1965b).…”