title: Humoral immune response to cruzipain and cardiac dysfunction in chronic Chagas disease.
abstract: The humoral immune response to epitopes expressed on cruzipain was evaluated in 31 Chagas disease patients (CDP) with different degrees of cardiac dysfunction. We took advantage of the availability of anti-Trypanosoma cruzi microsomal fraction monoclonal antibodies (MoAbs) reactive with epitopes that are recognized (5A9B11) or not recognized (1A10C11) by CDP sera. The 5A9B11- and 1A10C11-like epitopes are expressed on cruzipain. The reactivity of 5A9B11 against cruzipain was completely inhibited by sera of severe cardiopathy patients while a partial inhibition was found with sera from chagasic patients with mild disease. CDP sera did not block cruzipain recognition by 1A10C11. The antigenic determinants recognized by CDP sera appeared to be linear and carbohydrate free. When the overall anti-cruzipain immune response was evaluated, 70% of CDP with severe disease showed cruzipain titers higher than 1/800 while none of them displayed titers lower that 1/400. This report shows for the first time that the humoral immune response against epitopes expressed on cruzipain appeared to be related with the severity of chronic Chagas disease.
authors.affiliation: Instituto de Investigaciones Biotecnólogicas, Universidad Nacional de General San Martín, INTI. Av. Gral. Paz entre Albarellos y Constituyentes (Edificio 24) Casilla de Correo 30 (1650), San Martín, Buenos Aires, Argentina.
authors.forename: V G
authors.initials: VG
authors.lastname: Duschak
authors.forename: A
authors.initials: A
authors.lastname: Riarte
authors.forename: E L
authors.initials: EL
authors.lastname: Segura
authors.forename: S A
authors.initials: SA
authors.lastname: Laucella
mesh_terms: D000328:Adult; D000368:Aged; D019138:Antibodies, Blocking / Q000097:blood; D000913:Antibodies, Protozoan / Q000096:biosynthesis* / Q000097:blood / Q000378:metabolism; D000918:Antibody Specificity / Q000276:immunology; D000953:Antigens, Protozoan / Q000737:chemistry / Q000276:immunology; D001666:Binding Sites, Antibody; D001667:Binding, Competitive / Q000276:immunology; D002241:Carbohydrates / Q000097:blood / Q000276:immunology; D002598:Chagas Cardiomyopathy / Q000097:blood / Q000276:immunology* / Q000503:physiopathology*; D002908:Chronic Disease; D003546:Cysteine Endopeptidases / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D000939:Epitopes / Q000097:blood / Q000737:chemistry / Q000276:immunology; D006801:Humans; D008875:Middle Aged; D015800:Protozoan Proteins
chemical_list: D019138:Antibodies, Blocking; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D002241:Carbohydrates; D000939:Epitopes; D015800:Protozoan Proteins; D003546:Cysteine Endopeptidases; C063214:cruzipain