title: Identification of novel diagnostic serum biomarkers for Chagas' disease in asymptomatic subjects by mass spectrometric profiling.
abstract: More than 10 million people are thought to be infected with Trypanosoma cruzi, primarily in the Americas. The clinical manifestations of Chagas' disease (CD) are variable, but most subjects remain asymptomatic for decades. Only 15 to 30% eventually develop terminal complications. All current diagnostic tests have limitations. New approaches are needed for blood bank screening as well as for improved diagnosis and prognosis. Sera from subjects with asymptomatic CD (n = 131) were compared to those from uninfected controls (n = 164) and subjects with other parasitic diseases (n = 140), using protein array mass spectrometry. To identify biomarkers associated with CD, sera were fractionated by anion-exchange chromatography and bound to two commercial ProteinChip array chemistries: WCX2 and IMAC3. Multiple candidate biomarkers were found in CD sera (3 to 75.4 kDa). Algorithms employing 3 to 5 of these biomarkers achieved up to 100% sensitivity and 98% specificity for CD. The biomarkers most useful for diagnosis were identified and validated. These included MIP1 alpha, C3a anaphylatoxin, and unusually truncated forms of fibronectin, apolipoprotein A1 (ApoA1), and C3. An antipeptide antiserum against the 28.9-kDa C terminus of the fibronectin fragment achieved good specificity (90%) for CD in a Western blot format. We identified full-length ApoA1 (28.1 kDa), the major structural and functional protein component of high-density lipoprotein (HDL), as an important negative biomarker for CD, and relatively little full-length ApoA1 was detected in CD sera. This work provides proof of principle that both platform-dependent (i.e., mass spectrometry-based) and platform-independent (i.e., Western blot) tests can be generated using high-throughput mass profiling.
authors.affiliation: National Reference Centre for Parasitology, Research Institute of the McGill University Health Center, Montreal, Quebec, Canada. momar.ndao@mcgill.ca
authors.forename: Momar
authors.initials: M
authors.lastname: Ndao
authors.forename: Terry W
authors.initials: TW
authors.lastname: Spithill
authors.forename: Rebecca
authors.initials: R
authors.lastname: Caffrey
authors.forename: Hongshan
authors.initials: H
authors.lastname: Li
authors.forename: Vladimir N
authors.initials: VN
authors.lastname: Podust
authors.forename: Regis
authors.initials: R
authors.lastname: Perichon
authors.forename: Cynthia
authors.initials: C
authors.lastname: Santamaria
authors.forename: Alberto
authors.initials: A
authors.lastname: Ache
authors.forename: Mark
authors.initials: M
authors.lastname: Duncan
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Powell
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Ward
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000569:Americas; D000818:Animals; D015415:Biomarkers; D014355:Chagas Disease / Q000175:diagnosis*; D002648:Child; D019411:Clinical Laboratory Techniques / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D013058:Mass Spectrometry / Q000379:methods*; D008875:Middle Aged; D011506:Proteins / Q000032:analysis*; D012680:Sensitivity and Specificity; D044967:Serum / Q000737:chemistry*; D014349:Trypanosoma cruzi; D055815:Young Adult
chemical_list: D015415:Biomarkers; D011506:Proteins