Abstract
Culture of Plasmodium falciparum in age-fractionated thalassaemic red blood cells (RBC) has shown evidence of parasite damage on light microscopy in older cells during the third culture cycle (96–l44 h). In this report, parasites growing in thalassaemic trait and normal RBC were examined ultrastructurally from 96 to l44 h. All parasite stages in old thalassaemic RBC showed evidence of damage worsening with culture duration. There were cytoplasmic alterations with ribosomal damage, and parasite cytoplasm became increasingly loose and grainy, with multiple fissures. Discontinuity of the nuclear membrane with an abnormal nucleolus was seen at l20 h. Cytosomes remained normal, but damage to the food vacuole and shrunken disintegrating parasites were observed at 144 h. These changes are compatible with cellular degeneration and developmental retardation and would account for the schizont maturation arrest and reduced reinvasion rates previously reported. Increased free radicals associated with thalassaemic erythrocytes would explain these changes, further supporting the role for oxidant stress in the protective mechanism.
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References
Atkinson CT, Aikawa M (1990). Ultrastructure of malaria-infected erythrocytes. Blood Cells 16(35):1–368
Eaton JW, Eckman JR, Berger E, Jacob HS (1976) Suppression of malaria infection by oxidant-sensitive host erythrocytes. Nature 264:758–760
Luzzi GA, Merry AH, Newbold CI, Marsh K, Pasvol G (1991). Protection by α-thalassaemia against Plasmodium falciparum malaria: modified surface antigen expression rather than impaired growth or cytoadherence. Immunol Lett 30:233–240
Mackenstedt U, Mehlhorn H, Brockelman CR (1989) Ultrastructural study on the interaction of beta-thalassemic–erythrocytes and Plasmodium falciparum. Zentralbl Bakteriol 271:356–363
Olliaro P, Castelli F (1997) Plasmodium falciparum: an electron microscopy study of caveolae and trafficking between the parasite and the extracellular medium. Int J Parasitol 27:1007–1012
Olliaro PL, Goldberg DE (1995) The Plasmodium digestive vacuole: metabolic headquarters and choice drug target. Parasitol Today 11:294–297
Oppenheimer SJ, Higgs DR, Weatherall DJ, Barker J, Spark RA (1984) Alpha thalassaemia in Papua New Guinea. Lancet 1:424–426
Senok AC, Li K, Nelson EAS, Yu LM, Tian LP, Oppenheimer SJ (1997a) P. falciparum activity inhibited in fractionated thalassaemic erythrocytes. Trans R Soc Trop Med Hyg 91:138–143
Senok AC, Nelson EAS, Li K, Oppenheimer SJ (1997b) Thalassaemia trait, red blood cell age and oxidant stress: effects on Plasmodium falciparum growth and sensitivity to artemisinin. Trans R Soc Trop Med Hyg 91:585–589
Senok AC, Li K, Nelson EAS, Arumanayagam M, Li CK (1998) Flow cytometric assessment of oxidant stress in age-fractionated thalassaemic trait erythrocytes and its relationship to in vitro growth of Plasmodium falciparum. Parasitology 116:1–6
Udomsangpetch R, Sueblinvong T, Pattanapanyasat K, Dharmkrong-At A, Kittikalayawong A, Webster HK (1993) Alteration in cytoadherence and rosetting of Plasmodium falciparum-infected thalassemic red blood cells. Blood 82:3752–3759
Acknowledgements
We are grateful to Prof. Rieckman, Army Malaria Research Unit, Sydney, Australia, for providing us with the FC27 strain of P. falciparum. Thanks to Dr. F.M. Lai and Ms. J. Cheng, Anatomical and Cellular Pathology department, The Chinese University of Hong Kong, for assistance with transmission electron microscopy. Financial support was from the Croucher Foundation and the Research Grants Council (Hong Kong).
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Senok, A.C., Nelson, E.A.S., Li, K. et al. Ultrastructural assessment of Plasmodium falciparum in age-fractionated thalassaemic erythrocytes. Parasitol Res 98, 381–384 (2006). https://doi.org/10.1007/s00436-005-0061-3
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DOI: https://doi.org/10.1007/s00436-005-0061-3