title: Sialic acids and autoimmune disease.
abstract: An important underlying mechanism that contributes to autoimmunity is the loss of inhibitory signaling in the immune system. Sialic acid-recognizing Ig superfamily lectins or Siglecs are a family of cell surface proteins largely expressed in hematopoietic cells. The majority of Siglecs are inhibitory receptors expressed in immune cells that bind to sialic acid-containing ligands and recruit SH2-domain-containing tyrosine phosphatases to their cytoplasmic tails. They deliver inhibitory signals that can contribute to the constraining of immune cells, and thus protect the host from autoimmunity. The inhibitory functions of CD22/Siglec-2 and Siglec-G and their contributions to tolerance and autoimmunity, primarily in the B lymphocyte context, are considered in some detail in this review. The relevance to autoimmunity and unregulated inflammation of modified sialic acids, enzymes that modify sialic acid, and other sialic acid-binding proteins are also reviewed.
authors.affiliation: Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA.|Departments of Medicine and Pathology, Harvard Medical School, Boston, MA, USA.|Deaprtment of Pathology, Brigham and Women's Hospital, Boston, MA, USA.
authors.forename: Vinay S
authors.initials: VS
authors.lastname: Mahajan
authors.affiliation: Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA.|Departments of Medicine and Pathology, Harvard Medical School, Boston, MA, USA.
authors.forename: Shiv
authors.initials: S
authors.lastname: Pillai
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000276:immunology*; D015551:Autoimmunity; D001402:B-Lymphocytes / Q000502:physiology*; D006801:Humans; D007108:Immune Tolerance; D037102:Lectins / Q000378:metabolism*; D051379:Mice; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D011947:Receptors, Antigen, B-Cell / Q000378:metabolism*; D051918:Sialic Acid Binding Ig-like Lectin 2 / Q000378:metabolism*; D063265:Sialic Acid Binding Immunoglobulin-like Lectins
chemical_list: D037102:Lectins; D011947:Receptors, Antigen, B-Cell; D051918:Sialic Acid Binding Ig-like Lectin 2; D063265:Sialic Acid Binding Immunoglobulin-like Lectins; C522403:Siglecg protein, mouse; D019158:N-Acetylneuraminic Acid
keywords: CD22; CMAH; SIAE; Siglecs; autoimmunity; sialic acids