title: Profile of autoantibodies against phosphorylcholine and cross-reactivity to oxidation-specific neoantigens in selective IgA deficiency with or without autoimmune diseases.
abstract: Immunoglobulin A deficiency (IgAD) is considered the most common form of primary immunodeficiency. The majority of IgA-deficient individuals are considered asymptomatic, even though IgAD has been associated with an increased frequency of recurrent infections, allergy, and autoimmune diseases. In this study we evaluate the Natural autoantibodies (NatAbs) reactivity to phosphorylcholine (PC) and to some pro-inflammatory molecules in IgAD with or without autoimmune disorders. We observed that in the absence of IgA there is an enhancement of IgG subclasses functioning as NatAbs against PC. Immunoglobulin G (IgG) against lipopolysaccharide, C-reactive protein, and IgA was found in IgAD, regardless of the autoimmune manifestations. Nonetheless, IgAD patients with autoimmune disease showed significantly higher IgG reactivity against pro-inflammatory molecules, such as cardiolipin, oxidized low-density lipoproteins, and phosphatidylserine, with positive correlation between them. In conclusion, the IgG NatAbs against PC may represent a compensatory defense mechanism against infections and control excess of inflammation, explaining the asymptomatic status in the IgA deficiency.
authors.affiliation: Laboratório de Investigação em Dermatologia e Imunodeficiências, LIM 56, Faculdade de Medicina da USP, Instituto de Medicina Tropical de São Paulo, São Paulo, Brazil.
authors.forename: Ana Elisa
authors.initials: AE
authors.lastname: Fusaro
authors.forename: Kristine
authors.initials: K
authors.lastname: Fahl
authors.forename: Elaine Cristina
authors.initials: EC
authors.lastname: Cardoso
authors.forename: Cyro Alves
authors.initials: CA
authors.lastname: de Brito
authors.forename: Cristina M A
authors.initials: CM
authors.lastname: Jacob
authors.forename: Magda
authors.initials: M
authors.lastname: Carneiro-Sampaio
authors.forename: Alberto J S
authors.initials: AJ
authors.lastname: Duarte
authors.forename: Maria Notomi
authors.initials: MN
authors.lastname: Sato
mesh_terms: D000293:Adolescent; D000328:Adult; D001323:Autoantibodies / Q000276:immunology / Q000378:metabolism*; D001324:Autoantigens / Q000276:immunology; D001327:Autoimmune Diseases / Q000150:complications / Q000276:immunology*; D002648:Child; D003429:Cross Reactions; D005260:Female; D006801:Humans; D017098:IgA Deficiency / Q000150:complications / Q000276:immunology*; D007074:Immunoglobulin G / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010084:Oxidation-Reduction; D010767:Phosphorylcholine / Q000276:immunology
chemical_list: D001323:Autoantibodies; D001324:Autoantigens; D007074:Immunoglobulin G; D010767:Phosphorylcholine