Trypanosoma cruzi: cell charge distribution

Abstract

SUMMARYDifferences in cell charge between epimastigote and trypomastigote populations were compared in Y, CI and Colombiana strains of T. cruzi. Trypomastigote populations were more homogenous in relation to cell charge than epimastigotes. This homogeneity of cell charge was not the result of the selection of trypomastigote sub-populations by thes host immunosystem, but may be the result of a surface coat formed by host blood components.

The surface charge of trypanosomatids

“…The application of anion exchange columns to the study of Trypanosomatids started with the necessity to develop an efficient method to separate trypomastigote forms of trypanosomes from blood cells or from other evolutive forms for biological, chemical or immunological studies (Lanham 1968, 1971, Lanham and Godfrey 1970, Al-Abbassy et al 1972, Howells and Chiari 1973, Jackson 1975, Goldberg et al 1976, Kreier et al 1977, Gutteridge et al 1978, Villalta and Leon 1979, Alvarenga and Brener 1979, Selden and Baker 1980, Langenbach 1985. On passing infected blood throughout a DEAEcellulose column the blood cells and platelets, which are very negative, were completely adsorbed while the parasites could be easily eluted (Lanham 1968, 1971, Lanham and Godfrey 1970.…”

“…It was observed that slender trypomastigotes are more negative than the broad ones (Souza 1982, loc.cit.). DEAE-cellulose columns have also been used for the purification of T. cruzi trypomastigotes from tissue and axenic culture (Al-Abbassy et al 1972, Goldberg et al 1976, Kreier et al 1977, Selden and Baker 1980, Langenbach 1985 and from feces of triatomines (Alvarenga and Brener 1979) where they are mixed with epimastigote forms. As these metacyclic trypomastigotes have a negative surface similar to that of bloodstream trypomastigotes and epimastigotes have a less negative surface it would be expected that during the process of separation the first forms to be eluted should be the epimastigotes.…”