title: A 12-mer repetitive antigenic epitope from Trypanosoma cruzi is a potential marker of therapeutic efficacy in chronic Chagas' disease.
abstract: The objective was to characterize a Trypanosoma cruzi repetitive amino acid sequence that can be used as a marker of therapeutic drug efficacy in patients with chronic Chagas' disease.
  
  
  
  Reactivities to the 3973 peptide were measured in 85 patients with Chagas' disease (41 in the asymptomatic stage and 44 in the cardiomyopathy stage) before and 9 and 24 months after benznidazole administration. Additionally, the levels of IL-6 and C-reactive protein were measured in serum samples from patients with cardiomyopathy.
  
  
  
  In 85% of the asymptomatic patients and 73% of the symptomatic chronic patients, modifications of the reactivity to the 3973 peptide were observed at 9 and 24 months post-benznidazole treatment. Significant variations in reactivities to the total antigens of T. cruzi were not observed at these times. Significant decreases in the reactivity to the 3973 peptide were observed after treatment in 20 of 41 (49%) asymptomatic patients and 15 of 44 (34%) cardiac chagasic patients (P < 0.001). In these patients, the decreases in reactivity at 24 months post-treatment were at least 40% lower than those detected before treatment. No correlations were found of the detected modifications in reactivity to the 3973 peptide after treatment with the levels of C-reactive protein or IL-6.
  
  
  
  Decreases in reactivity to the 3973 peptide may be relevant in the post-treatment follow-up of chronic chagasic patients.
authors.affiliation: Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada, Avda. del Conocimiento S/N, 18100 Granada, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Fernandez-Villegas
authors.affiliation: Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada, Avda. del Conocimiento S/N, 18100 Granada, Spain.
authors.forename: M Carmen
authors.initials: MC
authors.lastname: Thomas
authors.affiliation: Unidad Regional de Medicina Tropical, Hospital Virgen de la Arrixaca, Cra. Cartagena s/n El Palmar, 30120 Murcia, Spain.
authors.forename: Bartolomé
authors.initials: B
authors.lastname: Carrilero
authors.affiliation: Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada, Avda. del Conocimiento S/N, 18100 Granada, Spain Laboratorio de Parasitología Molecular, Pontificia Universidad Javeriana, Bogotá, Colombia.
authors.forename: Paola
authors.initials: P
authors.lastname: Lasso
authors.affiliation: Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada, Avda. del Conocimiento S/N, 18100 Granada, Spain.
authors.forename: Adriana
authors.initials: A
authors.lastname: Egui
authors.affiliation: Unidad Regional de Medicina Tropical, Hospital Virgen de la Arrixaca, Cra. Cartagena s/n El Palmar, 30120 Murcia, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Murcia
authors.affiliation: Unidad Regional de Medicina Tropical, Hospital Virgen de la Arrixaca, Cra. Cartagena s/n El Palmar, 30120 Murcia, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Segovia
authors.affiliation: Centro de Biología Molecular Severo Ochoa, CSIC-Universidad Autónoma de Madrid, Cantoblanco, Madrid, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Alonso
authors.affiliation: Instituto de Parasitología y Biomedicina López Neyra, Consejo Superior de Investigaciones Científicas (IPBLN-CSIC), PTS Granada, Avda. del Conocimiento S/N, 18100 Granada, Spain mclopez@ipb.csic.es.
authors.forename: Manuel Carlos
authors.initials: MC
authors.lastname: López
mesh_terms: D000328:Adult; D000953:Antigens, Protozoan / Q000097:blood / Q000276:immunology; D000981:Antiprotozoal Agents / Q000627:therapeutic use*; D015415:Biomarkers / Q000097:blood*; D002097:C-Reactive Protein / Q000032:analysis; D002598:Chagas Cardiomyopathy / Q000175:diagnosis* / Q000188:drug therapy*; D016903:Drug Monitoring / Q000379:methods*; D000939:Epitopes / Q000097:blood / Q000276:immunology; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D009593:Nitroimidazoles / Q000627:therapeutic use*; D013812:Therapeutics; D014349:Trypanosoma cruzi / Q000276:immunology / Q000302:isolation & purification*
chemical_list: D000953:Antigens, Protozoan; D000981:Antiprotozoal Agents; D015415:Biomarkers; D000939:Epitopes; C508600:IL6 protein, human; D015850:Interleukin-6; D009593:Nitroimidazoles; D002097:C-Reactive Protein; C009999:benzonidazole