Progress in the development of stable transfection in Eimeria tenella
Julie Clark and Fiona Tomley
Institute for Animal Health, Compton.
Many practical difficulties have to be overcome to
develop transfection techniques for Eimeria tenella because these parasites do
not invade and develop in vitro with sufficiently high efficiencies to allow the
screening for or propagation of transfected parasites. Recently we have made
significant progress in (1) the efficiency of electroporation and transient
transfection of E. tenella; (2) the development of more reliable methods for
infecting chickens with electroporated sporozoites; and (3) the administration
of drugs to establish an effective selection barrier in vivo.
In addition, we have for the first time expressed successfully at a high level the fluorescent marker protein YFP within E. tenella. These advances mean that we can now dose chickens with significant numbers of potentially transfected parasites, select progeny oocysts with an effective drug barrier and FACs sort these parasites before re-propagating them in vivo. Using these approaches stable integration of YFP into the E. tenella genome has been achieved.