Open AccessGlycoconjugates of Trypanosoma cruzi : A 74 kD antigen of trypomastigotes specifically reacts with lytic anti‐α‐galactosyl antibodies from patients with chronic Chagas disease
Author(s) -
Almeida Igor C.,
Krautz Greice M.,
Krettli Antoniana U.,
Travassos Luiz R.
Publication year - 1993
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.1860070603
Subject(s) - trypanosoma cruzi , glycoconjugate , lytic cycle , antibody , chagas disease , antigen , heterologous , lysis , biology , glycoprotein , microbiology and biotechnology , virology , immunology , chemistry , parasite hosting , biochemistry , virus , world wide web , computer science , gene
Protective, lytic antibodies are believed to be correlated with active Typanosoma cruzi infection. In patients with chronic infection, antibodies lysing trypomastigote forms recognize chiefly α‐galactosyl structures at the parasite surface. The target molecules on cell‐derived trypomastigotes that react with anti‐α‐galactosyl antibodies (anti‐Gal) from patients with chronic Chagas disease were investigated. Glycoconjugates were isolated from trypomastigotes and shown to absorb purified Chagasic (Ch) anti‐Gal effectively as well as lytic antibodies from Ch sera. Active fractions were F2 (74 kD and 95.6 kD) and F3 (120–200 kD). A differential reactivity with antibodies from untreated Ch patients (trypanolytic) and from treated, presumably cured, individuals (not trypanolytic) was evident using F2 and F3 antigenic fractions. No cross‐reactivity with heterologous sera (other infections) was observed. The F2 glycoconjugate (mostly 74 kD) can be used in the diagnosis of active Chagas infection, replacing the quantitative determination of complementmediated lysis. With the present sample of patients' sera and normal human sera, it showed 100% sensitivity and specificity. © 1993 Wiley‐Liss, Inc.