title: Autoimmunity in IgA deficiency: revisiting the role of IgA as a silent housekeeper.
abstract: Both systemic and organ-specific autoimmune diseases are major manifestations of IgA deficiency (IgAD), the most common primary immunodeficiency. In addition, to discuss the clinical findings of IgAD patients, we proposed a hypothesis to explain the high association with autoimmune phenomena. Based on observations, interactions of monomeric IgA with FcalphaRI result in a partial phosphorylation of FcRgamma-associated FcalphaRI, notably in the immunoreceptor tyrosine-based activation motif (ITAM) inducing the recruitment of the SHP-1 tyrosine phosphatase. This leads to deactivation of several activating pathways of the immune system including immunoreceptors that bear ITAM motif and ITAM-independent receptors. Consequently, inflammatory reactions and auto-immune process would be prevented.
authors.affiliation: Instituto da Criança, Hospital das Clinicas da Faculdade de Medicina, Universidade de São Paulo, Rua Oscar Freire 1961 apto 24. Cerqueira César CEP 05409.011 São Paulo, Brasil. miuki55@uol.com.br
authors.forename: Cristina M A
authors.initials: CM
authors.lastname: Jacob
authors.forename: Antonio C
authors.initials: AC
authors.lastname: Pastorino
authors.forename: Kristine
authors.initials: K
authors.lastname: Fahl
authors.forename: Magda
authors.initials: M
authors.lastname: Carneiro-Sampaio
authors.forename: Renato C
authors.initials: RC
authors.lastname: Monteiro
mesh_terms: D000230:Adenocarcinoma / Q000209:etiology / Q000276:immunology; D001327:Autoimmune Diseases / Q000453:epidemiology / Q000209:etiology / Q000276:immunology; D015551:Autoimmunity; D001938:Brazil; D006801:Humans; D017098:IgA Deficiency / Q000150:complications / Q000453:epidemiology / Q000235:genetics* / Q000276:immunology*; D018928:Immunity, Mucosal; D018448:Models, Immunological; D009894:Opportunistic Infections / Q000276:immunology; D015995:Prevalence; D011961:Receptors, Fc / Q000235:genetics / Q000276:immunology; D017634:Self Tolerance; D015398:Signal Transduction; D013274:Stomach Neoplasms / Q000209:etiology / Q000276:immunology
chemical_list: D011961:Receptors, Fc