Highly effective serodiagnosis for Chagas' disease.
Many proteins of Trypanosoma cruzi, the causative agent of Chagas' disease, contain characteristic arrays of highly repetitive immunogenic amino acid motifs. Diagnostic tests using these motifs in monomeric or dimeric form have proven to provide markedly improved specificity compared to conventional tests based on crude parasite extracts. However, in many cases the available tests still suffer from limited sensitivity. In this study we produced stable synthetic genes with maximal codon variability for the four diagnostic antigens, B13, CRA, TcD, and TcE, each containing between three and nine identical amino acid repeats. These genes were combined by linker sequences encoding short proline-rich peptides, giving rise to a 24-kDa fusion protein which was used as a novel diagnostic antigen in an enzyme-linked immunosorbent assay setup. Validation of the assay with a large number of well-characterized patient sera from Bolivia and Brazil revealed excellent diagnostic performance. The high sensitivity of the new test may allow future studies to use blood collected by finger prick and dried on filter paper, thus dramatically reducing the costs and effort for the detection of T. cruzi infection.
Hernández
Pilar
P
University of Giessen, Institute of Biochemistry, Friedrichstrasse 24, Giessen, Germany.
Heimann
Michael
M
Riera
Cristina
C
Solano
Marco
M
Santalla
José
J
Luquetti
Alejandro O
AO
Beck
Ewald
E
D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000235:genetics; D001838:Bolivia; D001938:Brazil; D014355:Chagas Disease / Q000175:diagnosis*; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D006801:Humans; D008969:Molecular Sequence Data; D010274:Parasitology / Q000379:methods*; D011993:Recombinant Fusion Proteins / Q000235:genetics; D012680:Sensitivity and Specificity; D017422:Sequence Analysis, DNA; D012698:Serologic Tests / Q000379:methods; D014349:Trypanosoma cruzi / Q000276:immunology*
D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D011993:Recombinant Fusion Proteins