title: Retinal dysfunction in patients with chronic Chagas' disease is associated to anti-Trypanosoma cruzi antibodies that cross-react with rhodopsin.
abstract: To investigate retinal involvement in chronic Chagas' disease, we performed electroretinography and retinal fluorescein angiography studies in chagasic patients. Our results demonstrated a dissociated electrophysiological response characterized by both an abnormal reduction of the electroretinographic b-wave amplitude and a delayed latency, under the dark-adaptated condition. These alterations are compatible with a selective dysfunction of the rods. Antibodies raised against Trypanosoma cruzi that also interact with beta1-adrenergic receptor blocked light stimulation of cGMP-phosphodiesterase in bovine rod membranes. The specificity from the antibody-rhodopsin interaction was confirmed by Western blot analysis and antigenic competition experiments. Our results suggest an immunomediated rhodopsin blockade. T. cruzi infection probably induces an autoimmune response against rhodopsin in the chronic phase of Chagas' disease through a molecular mimicry mechanism similar to that described previously on cardiac human beta1-adrenergic and M2-cholinergic receptors, all related to the same subfamily of G-protein-coupled receptors.
authors.affiliation: Department of Neurology, Hospital Dr. Teodoro Alvarez, Buenos Aires, Argentina.
authors.forename: Silvia C
authors.initials: SC
authors.lastname: Matsumoto
authors.forename: Vivian
authors.initials: V
authors.lastname: Labovsky
authors.forename: Marcela
authors.initials: M
authors.lastname: Roncoroni
authors.forename: María C
authors.initials: MC
authors.lastname: Guida
authors.forename: Luisa
authors.initials: L
authors.lastname: Giménez
authors.forename: Jorge
authors.initials: J
authors.lastname: Mitelman
authors.forename: Horacio
authors.initials: H
authors.lastname: Gori
authors.forename: Renata
authors.initials: R
authors.lastname: Jurgelevicius
authors.forename: Alejandro
authors.initials: A
authors.lastname: Grillo
authors.forename: Pablo
authors.initials: P
authors.lastname: Manfredi
authors.forename: Mariano J
authors.initials: MJ
authors.lastname: Levin
authors.forename: Cristina
authors.initials: C
authors.lastname: Paveto
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000502:physiology; D000328:Adult; D000595:Amino Acid Sequence; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood / Q000276:immunology*; D001327:Autoimmune Diseases / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D002417:Cattle; D014355:Chagas Disease / Q000150:complications / Q000276:immunology*; D003429:Cross Reactions; D004596:Electroretinography; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D018716:Molecular Mimicry; D008969:Molecular Sequence Data; D011930:Reaction Time; D018342:Receptors, Adrenergic, beta-1 / Q000276:immunology; D012164:Retinal Diseases / Q000209:etiology* / Q000276:immunology / Q000503:physiopathology; D017948:Retinal Rod Photoreceptor Cells / Q000276:immunology* / Q000503:physiopathology / Q000528:radiation effects; D012243:Rhodopsin / Q000276:immunology*; D012374:Rod Cell Outer Segment / Q000276:immunology; D015398:Signal Transduction / Q000528:radiation effects; D014349:Trypanosoma cruzi / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D018342:Receptors, Adrenergic, beta-1; D012243:Rhodopsin; D015106:3',5'-Cyclic-GMP Phosphodiesterases