Effects of dimethylsulfoxide and the deep-freezing process on the infectivity, motility, and ultrastructure of Trypanosoma cruzi

Abstract

The effects of dimethylsulfoxide (DMSO, final concentration 5%) and the deep-freezing process on the infectivity (ID50), motility, and ultrastructure of nontreated and DMSO-treated Trypanosoma cruzi suspensions (PSG-3 buffer with 10% horse serum) were investigated prior to and after cryopreservation in liquid nitrogen. DMSO equilibration caused distinct suppression of motility and characteristic, fine structural alterations in numerous organelles, such as myelin-like structures in the cytoplasm and/or inside the mitochondrial apparatus, enlargement of the perinuclear space, endoplasmic reticulum, and mitochondrial cristae, as well as condensation of the kinetoplast with loss of its lamellar structure. There was no evidence of loss of infectivity in DMSO-treated parasites. DMSO-treated and deep-frozen organisms showed, however, very similar fine structural alterations, although damage occurring during freezing and thawing was more pronounced. Apart from the frequently enlarged kinetoplast and the loosening of its mitochondrial matrix, numerous trypanosomes revealed total disintegration of the kinetoplast-mitochondrion complex with loss of its whole matrix. Deep-frozen trypanosomes were significantly less infective to mice than nontreated organisms, and their motility was strongly suppressed. These results suggest that cryopreservation and thawing of T. cruzi may lead to severe damage of the mitochondrial apparatus and thus to heavy disorders of metabolic function, exhaustion of the metabolic pool, and finally, to death of such damaged trypanosomes, despite the use of DMSO as a cryoprotective agent.

Epidemiologic and laboratory findings from 3 years of testing United States blood donors for Trypanosoma cruzi

“…In addition, the only implicated products have been PLTs with no evidence of plasma or red blood cells (RBCs) responsible for the very rare cases of transfusion transmission. Current blood bank practices including cold storage of RBCs, preparation of frozen plasma, and leukoreduction likely contribute to the reduced capacity of certain components to transmit infection 39 …”

FT‐IR spectroscopic studies on molecular interactions of cryoprotectant agents with bacteria

“…Actually, MezSO can interact with different biomolecules: proteins, nucleic acids, carbohydrates, lipids, and especially water, with which MezSO associates through dipole-dipole interactions and hydrogen bonding. 43 Associations can also occur between MezSO and unshared electron pairs of amines, oxygen in alcohol and esters, to quote only a few example^.^ Our infrared results together with literature data5r3' suggest the existence of interactions between MeeSO and a wide range of bacterial components.…”

One-Pot Multicomponent Synthesis of Methoxybenzo[h]quinoline-3-carbonitrile Derivatives; Anti-Chagas, X-ray, and In Silico ADME/Tox Profiling Studies

“…The concentrations of each compound were evaluated in triplicate. The plates were incubated at 4 • C for 24 h. The trypanocidal activity was evaluated by counting the number of bloodstream trypomastigotes after the incubation time by the Brener method [43][44][45]. Briefly, 5 mL of blood were placed on slides, covered with a coverslip, and the flagellates were examined with an optical microscope at 40× magnification.…”