Cysteine proteinase in Trypanosoma cruzi: Immunocytochemical localization and involvement in parasite-host cell interaction

Abstract

A monospecific polyclonal antibody obtained against a cysteine proteinase isolated from epimastigotes of Trypanosoma cruzi was used for the immunocytochemical localization of the protein by electron microscopy and to analyse the role played by cysteine proteinase in the process of T. cruzi-host cell interaction. Cytoplasmic structures that correspond to elements of the endosomal-lysosomal (reservosome) system found in epimastigote, amastigote and trypomastigote forms reacted intensely with colloidal gold-labelled antibodies using on-section indirect labelling. The surface of most of the tissue culture-derived trypomastigotes was not labelled. However, the flagellar pocket of this form was labelled. All epimastigotes obtained from axenic cultures and amastigote-like forms found in the supernatant of vertebrate cells heavily infected with T. cruzi had their surface intensely labelled, indicating also the surface localization of the protein. Incubation of the parasites in the presence of a sub-agglutinating concentration of the anti-cysteine proteinase antibody led to a marked increase in their uptake by macrophages. In contrast, addition of the F(ab')2 portion of the same antibody significantly reduced the uptake of the parasites by the macrophages. The results obtained strongly suggest an important participation of cysteine proteinase in the process of T. cruzi-macrophage interaction.

Fexinidazole interferes with the growth and structural organization of Trypanosoma cruzi

“…On the other hand, the intense disorganization of reservosomes, also reported in this work, could be a consequence of endocytosis impairment and could even interfere with epimastigotes proliferation [17][18][19] . Furthermore, reservosome is the organelle where a high concentration of cruzipain is found 20 , an essential enzyme for parasite virulence, host cell invasion and differentiation, and an important chemotherapeutic target, as well 21 . Adding to the ultrastructural alterations reported in the reservosomes, our results suggest that FEX could also act on cruzipain.…”

Do thiazolidine compounds act on intracellular amastigotes of Trypanosoma cruzi? A systematic review

“…Cruzain can appear in two locations in T. cruzi intracellular amastigotes: on the surface of the parasite, directly in contact with the host cell cytoplasm, as well as in the lysosome-related compartment (Souto-Padron et al, 1990., Engel et al 2000., Vieira et al, 2005. In general, the literature reports that cruzipain inhibitors, such as diazomethane inhibitors, fluoromethyl ketones, oxygen-containing heterocycles and vinyl sulfones are considered promising agents for the treatment of CD in the chronic phase (Kouznetsov, 2019).…”

Design, Synthesis, and Evaluation of Hydroxamic Acid Derivatives as Promising Agents for the Management of Chagas Disease

“…The highly infected cells ruptured, releasing amastigote forms of T. cruzi after 3−5 days of infection. 45 Human acute monocytic leukemia cells lines (THP-1) were maintained in DMEM supplemented with 10% fetal bovine serum and antibiotics (100 μg/mL of streptomycin and 100 μg/mL of penicillin G). Macrophages were obtained by injecting thioglycollate 46 SDS, and 20% glycerol with or without 0.002% bromophenol blue) and stored on ice.…”

“…The highly infected cells ruptured, releasing amastigote forms of T. cruzi after 3–5 days of infection . Human acute monocytic leukemia cells lines (THP-1) were maintained in DMEM supplemented with 10% fetal bovine serum and antibiotics (100 μg/mL of streptomycin and 100 μg/mL of penicillin G).…”