Cardiac Autoantibodies from Patients Affected by a New Variant of Endemic Pemphigus Foliaceus in Colombia, South America

• Published in: Journal of clinical immunology Vol. 31; no. 6; pp. 985 - 997
• Main Authors: Abreu-Velez, Ana Maria, Howard, Michael S., Jiao, Zhe, Gao, Weiqing, Yi, Hong, Grossniklaus, Hans E., Duque-Ramírez, Mauricio, Dudley, Samuel C.
• Format: Journal Article
• Language: English
• Published: Boston Springer US 01-12-2011; Springer Nature B.V
• Subjects: adherens junctions; Adult; Age; Animals; Antigen-Antibody Complex - metabolism; Autoantibodies; Autoantibodies - immunology; Autoantibodies - metabolism; Autoantigens; Autoantigens - immunology; Autoantigens - metabolism; Bagre; Biomedical and Life Sciences; Biomedicine; Blood vessels; Cadherins - immunology; Cadherins - metabolism; Carditis; Cattle; Cell Adhesion Molecules - immunology; Cell Adhesion Molecules - metabolism; Cell junctions; Colombia; Confocal microscopy; Connexin 43; Connexin 43 - immunology; Connexin 43 - metabolism; Cytoskeletal Proteins - immunology; Cytoskeletal Proteins - metabolism; Death, Sudden, Cardiac; Desmoplakins - immunology; Desmoplakins - metabolism; Endemic Diseases; Epitopes; ezrin; Gap junctions; Heart; Heart - physiology; Heart - physiopathology; Humans; Immune response; Immunoblotting; Immunoelectron microscopy; Immunofluorescence; Immunohistochemistry; Immunology; Infectious Diseases; Intercellular Junctions - ultrastructure; Internal Medicine; Medical Microbiology; Mice; Microscopy, Electron; Middle Aged; Myocardium - immunology; Myocardium - metabolism; Myocardium - ultrastructure; Pemphigus; Pemphigus - epidemiology; Pemphigus - immunology; Pemphigus - mortality; Pemphigus - physiopathology; Pemphigus foliaceus; Purkinje fibers; Rats; Receptors, Cell Surface - immunology; Receptors, Cell Surface - metabolism; Sarcomeres; sudden death syndrome; Tight junctions; Young Adult; Colombia; Heart; cell junctions; endemic pemphigus foliaceus; autoimmunity; plakins; area composita
• ISSN: 0271-9142; 1573-2592; 1573-2592
• DOI: 10.1007/s10875-011-9574-y

Several patients affected by a new variant of endemic pemphigus foliaceus in El Bagre, Colombia (El Bagre-EPF) have experienced a sudden death syndrome, including persons below the age of 50. El Bagre-EPF patients share several autoantigens with paraneoplastic pemphigus patients, such as reactivity to plakins. Further, paraneoplastic pemphigus patients have autoantibodies to the heart. Therefore, we tested 15 El Bagre-EPF patients and 15 controls from the endemic area for autoreactivity to heart tissue using direct and indirect immunofluorescence, confocal microscopy, immunohistochemistry, immunoblotting, and immunoelectron microscopy utilizing heart extracts as antigens. We found that 7 of 15 El Bagre patients exhibited a polyclonal immune response to several cell junctions of the heart, often colocalizing with known markers. These colocalizing markers included those for the area composita of the heart, such as anti-desmoplakins I and II; markers for gap junctions, such as connexin 43; markers for tight junctions, such as ezrin and junctional adhesion molecule A; and adherens junctions, such pan-cadherin. We also detected colocalization of the patient antibodies within blood vessels, Purkinje fibers, and cardiac sarcomeres. We conclude that El Bagre-EPF patients display autoreactivity to multiple cardiac epitopes, that this disease may resemble what is found in patients with rheumatic carditis, and further, that the cardiac pathophysiology of this disorder warrants further evaluation.