Trypanosoma cruzi: differential expression and distribution of an 85-kDa polypeptide epitope by in vitro developmental stages
Détails
ID Serval
serval:BIB_D50D2026391C
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Trypanosoma cruzi: differential expression and distribution of an 85-kDa polypeptide epitope by in vitro developmental stages
Périodique
Experimental Parasitology
ISSN
0014-4894 (Print)
Statut éditorial
Publié
Date de publication
08/1990
Volume
71
Numéro
2
Pages
207-17
Notes
Journal Article
Research Support, Non-U.S. Gov't --- Old month value: Aug
Research Support, Non-U.S. Gov't --- Old month value: Aug
Résumé
The expression by Trypanosoma cruzi developmental stages of an 85-kDa polypeptide epitope defined by the 155D3 monoclonal antibody (mAb) has been investigated. Immunoprecipitation revealed the presence of an 85-kDa antigen in the NP-40 soluble extract of parasites freshly released from infected fibroblasts; this antigen was not found in epimastigote and Leishmania infantum promastigote. Indirect immunofluorescence revealed that the mAb 155D3 failed to react with trypomastigotes, whereas extracellular amastigotes were heavily stained. Positive organisms displayed either surface or polar fluorescence. Since the same mAb immunoprecipitated the 85-kDa antigen in both radioactive iodine- and methionine-labeled trypomastigote detergent soluble extracts, the reactive epitope is likely to be hidden in a cryptic site in trypomastigotes. An alternative explanation for the negative immunofluorescence on trypomastigotes and the positive immunoprecipitation is the presence, in the extracts, of a small population of parasites already expressing the 155D3 epitope. Immunoelectron microscopy revealed that the target epitope is heterogenously distributed among the populations of differentiating parasites. Two types of immunogold labeling were observed: (a) mAb revealed a high amount of reactive material associated with the periphery of the parasites and (b) a label was observed on the inner surface of peripheral vacuoles that might correspond to cross sections of inflated flagellar pockets and in association with vesicles which were released by the parasites. The surface expression of the epitope recognized by the 155D3 mAb was followed by fluorescence-activated cell-sorting analysis. The results showed that the epitope is increasingly accessible during trypomastigote differentiation in vitro. Taken together, these results suggest that the epitope reacting with the 155D3 mAb is heavily expressed on extracellular amastigotes after the transformation process and, thus, appears to be developmentally regulated.
Mots-clé
Animals
Antibodies, Monoclonal/immunology
Antigens, Protozoan/analysis/*biosynthesis
Electrophoresis, Gel, Two-Dimensional
Electrophoresis, Polyacrylamide Gel
Epitopes/analysis/biosynthesis
Fluorescent Antibody Technique
Immunohistochemistry
Microscopy, Electron
Precipitin Tests
Trypanosoma cruzi/growth & development/*immunology/ultrastructure
Pubmed
Web of science
Création de la notice
28/01/2008 9:31
Dernière modification de la notice
20/08/2019 15:54