title: Human recombinant antibodies against Trypanosoma cruzi ribosomal P2β protein.
abstract: Patients with chronic Chagas' Heart Disease (cChHD) develop an antibody response that is suspected to be involved in the cardiac pathogenesis. The response against Trypanosoma cruzi ribosomal P proteins is of particular interest, as these antibodies can cross-react with host cardiac receptors causing electrophysiological alterations. To better understand the humoral anti-P response we constructed a single-chain variable fragment library derived from a cChHD patient. The variable heavy and light regions were amplified from bone-marrow RNA and subcloned into the vector pComb3X. The phage library was subsequently panned against T. cruzi ribosomal P2β protein (TcP2β). We obtained 3 different human recombinant antibodies that specifically reacted with TcP2β in ELISA and Western blots. Two of them reacted with the C-terminal region of TcP2β, peptide R13, as the recombinant autoanti-P antibodies from Systemic Lupus Erythematosus (SLE) patients. Interestingly, the third one was specific for TcP2β but did not recognize R13, confirming the specific nature of the anti-P response in Chagas disease. Neither sequence nor VH usage similarities between Chagas and SLE anti-P autoantibodies were observed. Herein, the first human mAbs against TcP2β have been obtained and characterized showing that the humoral anti-P response is directed against the parasite and does not include an autoimmune component.
authors.affiliation: Laboratory of Molecular Biology of Chagas' Disease, Institute for Genetic Engineering and Molecular Biology (INGEBI), CONICET-UBA, 1428 Ciudad autónoma de Buenos Aires, Argentina.
authors.forename: Vanina
authors.initials: V
authors.lastname: Grippo
authors.affiliation: Laboratory of Molecular Biology of Chagas' Disease, Institute for Genetic Engineering and Molecular Biology (INGEBI), CONICET-UBA, 1428 Ciudad autónoma de Buenos Aires, Argentina.
authors.forename: Leticia L
authors.initials: LL
authors.lastname: Niborski
authors.affiliation: Laboratory of Molecular Biology of Chagas' Disease, Institute for Genetic Engineering and Molecular Biology (INGEBI), CONICET-UBA, 1428 Ciudad autónoma de Buenos Aires, Argentina.
authors.forename: Karina A
authors.initials: KA
authors.lastname: Gomez
authors.affiliation: Laboratory of Molecular Biology of Chagas' Disease, Institute for Genetic Engineering and Molecular Biology (INGEBI), CONICET-UBA, 1428 Ciudad autónoma de Buenos Aires, Argentina.
authors.forename: Mariano J
authors.initials: MJ
authors.lastname: Levin
mesh_terms: D000595:Amino Acid Sequence; D000913:Antibodies, Protozoan / Q000737:chemistry / Q000378:metabolism*; D001853:Bone Marrow / Q000276:immunology; D002598:Chagas Cardiomyopathy / Q000276:immunology*; D014355:Chagas Disease / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D015723:Gene Library; D006801:Humans; D008180:Lupus Erythematosus, Systemic / Q000276:immunology; D010750:Phosphoproteins / Q000737:chemistry / Q000276:immunology*; D015800:Protozoan Proteins / Q000737:chemistry; D011994:Recombinant Proteins / Q000737:chemistry / Q000276:immunology; D012269:Ribosomal Proteins / Q000737:chemistry / Q000276:immunology*; D016415:Sequence Alignment; D014349:Trypanosoma cruzi / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D010750:Phosphoproteins; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D012269:Ribosomal Proteins; C031937:phosphoprotein P2, ribosomal