Relapse of monomorphic and pleomorphicTrypanosoma brucei infections in the mouse after chemotherapy
- 28 Downloads
Infections in mice were initiated with trypomastigotes from two lines ofTrypanosoma brucei derived from the same primary isolate. Infections with one line were initiated by inoculation of metacyclic trypomastigotes from infected tsetse flies and the resulting infections were pleomorphic. The other line had been passaged 32 times in rodents and inoculation of blood-stream trypomastigotes gave rise to monomorphic infections. In both infections there were high levels of parasitaemia until death up to 4 weeks later if the infection was untreated. It was shown that after chemotherapy with 40 mg/kg diminazene aceturate (Berenil) relapses occurred in both types of infection after an aparasitaemic period of 2–3 weeks. Further, it was shown that 3 days after chemotherapy, brain tissue but neither spleen, liver nor blood was capable of transferring infection to normal recipient mice.
There were two major differences in the response of the two infections to chemotherapy. First, treatment of the pleomorphic infection as soon as day 6 after infection resulted in a subsequent relapse while the monomorphic infection had to be at least 12 days old at the time of treatment before relapses occurred. Second, following treatment of the pleomorphic, but not of the monomorphic infection there was an early transient recrudescence of low numbers of trypanosomes which were found to be non-infective to recipient mice. The early transient relapse was followed by a further aparasitaemic period and then the late continuous relapse characterised by large numbers of infective trypanosomes.
KeywordsAceturate Brain Tissue Recipient Mouse Primary Isolate Subsequent Relapse
Unable to display preview. Download preview PDF.
- Ashcroft MT (1960) A comparison between a syringe-passaged and a tsetse-fly-transmitted line of a strain ofTrypanosoma rhodesiense. Ann Trop Med Parasitol 54:44–55Google Scholar
- Clarkson A, Brohn F (1976) Trypanosomiasis: an approach to chemotherapy by the inhibition of carbohydrate metabolism. Science 194:204–206Google Scholar
- Evans DA, Brightman CAJ (1980) Pleomorphism and the problem of recrudescent parasitaemia following treatment with salicylhydroxamic acid (SHAM) in African trypanosomiasis. Trans R Soc Trop Med Hyg 74:601–604Google Scholar
- Goodwin LG, Tierney ED (1977) Trypanocidal activity of blood and tissue fluid from normal and infected rabbits treated with curative drugs. Parasitology 74:33–45Google Scholar
- Hajduk SL (1978) Influence of DNA complexing compounds on the kinetoplast of trypanosomatids. Prog Mol Subcell Biol 6:158–200Google Scholar
- Hajduk SL, Cameron C, Barry JD, Vickerman K (1981) Antigenic variation in cyclically transmittedTrypanosoma brucei. Variable antigen type composition of metacyclic trypanosome populations from the salivary glands ofGlossina morsitans. Parasitology 83:595–607Google Scholar
- Herbert WJ, Lumsden WHR (1976)Trypanosoma brucei: a rapid “matching” method for estimating the host's parasitaemia. Exp Parasitol 40:427–431Google Scholar
- Hoare CA (1970) Systematic description of the mammalian trypanosomes of Africa. In: Mulligan HW (ed) The african trypanosomiases, George Allen and Unwin, London, p 24–59Google Scholar
- James DM (1978) Prophylactic activity in rodents of trypanocides complexed with dextran. Trans R Soc Trop Med Hyg 72:471–476Google Scholar
- Jennings FW, Whitelaw DD, Urquhart GM (1977) The relationship between duration of infection withTrypanosoma brucei in mice and the efficacy of chemotherapy. Parasitology 75:143–153Google Scholar
- Jennings FW, Whitelaw DD, Holmes PH, Chizyuka HGB, Urquhart GM (1979) The brain as a source of relapsingTrypanosoma brucei infection in mice after chemotherapy. Int J Parasitol 9:381–384Google Scholar
- LeRay D, Barry JD, Easton C, Vickerman K (1977) First tsetse fly transmission of the “AnTat” serodeme ofTrypanosoma brucei. Ann Soc Belge Med trop 57:369–381Google Scholar
- Lumsden WHR, Herbert WJ, Hardy GJC (1965) In vivo prophylactic activity of Berenil against trypanosomes in mice. Vet Rec 77:147–148Google Scholar
- Murgatroyd F, Yorke W, Corson JF (1937) Studies in chemotherapy XIII. The changes observed inT. brucei during five years maintenance in the laboratory. Ann Trop Med Parasitol 31:145–163Google Scholar
- Opperdoes FR, Aarsen PN, Van der Meer C, Borst P (1976)Trypanosoma brucei: an evaluation of salicylhydroxamic acid as a trypanocidal drug. Exp Parasitol 40:198–205Google Scholar
- Wijers DJB (1959) Polymorphism inTrypanosoma gambiense andTrypanosoma rhodesiense, and the significance of the intermediate forms. Ann Trop Med Parasitol 53:59–68Google Scholar
- Williamson J (1970) Review of chemoprophylactic agents. In: Mulligan HW (ed), The african trypanosomiases, George Allen and Unwin, London, p 125–221Google Scholar