Electron microscopy of trypanosomes: a historical view

Abstract

Since the discovery of the electron microscope and the development of the initial techniques for the processing of biological samples for electron microscopy, the protozoan Trypanosoma cruzi has been the subject of intense investigation. This review analyzes the results obtained by observation of whole trypanosomes as well as thin sections and replicas using several microscopic approaches. Micrographs detailing the appearance of T. cruzi using several methods illustrate the evolution of electron microscopic techniques as well as its contribution to understanding the structural organization of the protozoan.

In vitro effects of citral on Trypanosoma cruzi metacyclogenesis

“…Trypomastigotes were more susceptible to citral than epimastigotes and bloodstream trypomastigotes were more susceptible to citral than in vitro-derived metacyclic trypomastigotes. Because epimastigotes, bloodstream trypomastigotes and metacyclic trypomastigotes have different metabolisms and different glycoconjugate compositions at the cell membrane (de Andrade et al 1991, de Souza 2008, these different susceptibilities could be due to different cell permeability rates for citral or different cellular targets.…”

An Historical Perspective on How Advances in Microscopic Imaging Contributed to Understanding theLeishmaniaSpp. andTrypanosoma cruziHost-Parasite Relationship

“…In collaboration with Keith Porter from Rockefeller University in the USA, Hertha Meyer was the first investigator to register the ultrastructure of T. cruzi invertebrate forms (epimastigotes) using electron microscopy [65]. Interestingly, T. cruzi was one of the first cells observed with this technique [66]. Current detailed knowledge of internal structures of different morphological stages of the parasite has been acquired based on comprehensive transmission electron microscopy (TEM) data and gradual improvement of the technique over the years [66].…”

Contributions of Ultrastructural Studies to the Cell Biology of Trypanosmatids: Targets for Anti-Parasitic Drugs

“…1). Changes in composition of the organelles can be analyzed by cytochemical techniques, X-ray microanalysis or electron spectroscopy with loss of energy [8]. A brief explanation of the normal morphology of the parasites and the mechanism of action of the different classes of drugs will be presented.…”

“…Trypanosomatids have only one highly ramified mitochondrion distributed throughout the protozoan body as revealed by observations of thick serial sections and of whole cells with high-voltage electron microscopy [8]. The mitochondrion is present in all developmental forms of the different trypanosmatids, and significant changes in the morphology of the organelle were observed in African Trypanosomes and in Herpetomonas samuelpessoai depending on the metabolic activity of the parasites.…”

“…The nuclear envelope remains intact during the entire division process, with the appearance of intranuclear microtubules, chromatin dispersion and initiated formation of of dense plates, the number of which varies according to the trypanosomatid species [8].…”