Open Accessgp63 Homologues inTrypanosoma cruzi: Surface Antigens with Metalloprotease Activity and a Possible Role in Host Cell Infection
Author(s) -
Ileana Cuevas,
Juán José Cazzulo,
Daniel O. Sánchez
Publication year - 2003
Publication title -
infection and immunity
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.508
H-Index - 220
eISSN - 1070-6313
pISSN - 0019-9567
DOI - 10.1128/iai.71.10.5739-5749.2003
Subject(s) - biology , amastigote , trypanosoma cruzi , leishmania , blot , chagas disease , kinetoplastida , antigen , leishmania major , immunofluorescence , metalloproteinase , leishmania braziliensis , gene , microbiology and biotechnology , antibody , leishmaniasis , virology , cutaneous leishmaniasis , matrix metalloproteinase , biochemistry , parasite hosting , immunology , world wide web , computer science , protozoal disease , malaria
gp63 is a highly abundant glycosylphosphatidylinositol (GPI)-anchored membrane protein expressed predominantly in the promastigote but also in the amastigote stage of Leishmania species. In Leishmania spp., gp63 has been implicated in a number of steps in establishment of infection. Here we demonstrate that Trypanosoma cruzi, the etiological agent of Chagas' disease, has a family of gp63 genes composed of multiple groups. Two of these groups, Tcgp63-I and -II, are present as high-copy-number genes. The genomic organization and mRNA expression pattern were specific for each group. Tcgp63-I was widely expressed, while the Tcgp63-II group was scarcely detected in Northern blots, even though it is well represented in the T. cruzi genome. Western blots using sera directed against a synthetic peptide indicated that the Tcgp63-I group produced proteins of approximately 78 kDa, differentially expressed during the life cycle. Immunofluorescence staining and phosphatidylinositol-specific phospholipase C digestion confirmed that Tcgp63-I group members are surface proteins bound to the membrane by a GPI anchor. We also demonstrate the presence of metalloprotease activity which is attributable, at least in part, to Tcgp63-I group. Since antibodies against Tcgp63-I partially blocked infection of Vero cells by trypomastigotes, a possible role for this group in infection is suggested.