title: Analysis of celiac disease autoreactive gut plasma cells and their corresponding memory compartment in peripheral blood using high-throughput sequencing.
abstract: Autoreactive IgA plasma cells (PCs) specific for the enzyme transglutaminase 2 (TG2) are abundant in the small intestine of patients with active celiac disease (CD), and their number drops in patients treated by dietary gluten elimination. Little is known about their characteristics and their role in the disease. In this study, using high-throughput sequencing of the IgH V region (IGHV) genes, we have studied features of TG2-specific PCs and their related B cell clones in peripheral blood. We found that TG2-specific PCs from both untreated and treated patients have acquired lower number of somatic hypermutation and used focused IGHV repertoire with overrepresentation of the IGHV3-48, IGHV4-59, IGHV5-10-1, and IGHV5-51 gene segments. Furthermore, these PCs were clonally expanded and showed signs of affinity maturation. Lineage trees demonstrated shared clones between gut PCs and blood memory B cells, primarily IgAs. Some trees also involved IgG cells, suggesting that anti-TG2 IgA and IgG responses are related. Similarly to TG2-specific PCs, clonally related memory IgA B cells of blood showed lower mutation rates with biased usage of IGHV3-48 and IGHV5-51. Such memory cells were rare in peripheral blood, yet detectable in most patients assessed by production of anti-TG2 Abs in vitro following stimulation of cells from patients who had been on a long-term gluten-free diet. Thus, the Ab response to TG2 in CD, while maintaining its IGHV gene usage, is dynamically regulated in response to gluten exposure with a low degree of maintenance at both PC and memory B cell levels in patients in remission.
authors.affiliation: Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway;
authors.forename: Omri
authors.initials: O
authors.lastname: Snir
authors.affiliation: Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway;
authors.forename: Luka
authors.initials: L
authors.lastname: Mesin
authors.affiliation: Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramt Gan 52900, Israel; and.
authors.forename: Moriah
authors.initials: M
authors.lastname: Gidoni
authors.affiliation: Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway; Department of Gastroenterology, Oslo University Hospital-Rikshospitalet, 0372 Oslo, Norway.
authors.forename: Knut E A
authors.initials: KE
authors.lastname: Lundin
authors.affiliation: Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramt Gan 52900, Israel; and.
authors.forename: Gur
authors.initials: G
authors.lastname: Yaari
authors.affiliation: Centre for Immune Regulation and Department of Immunology, University of Oslo and Oslo University Hospital, 0372 Oslo, Norway; l.m.sollid@medisin.uio.no.
authors.forename: Ludvig M
authors.initials: LM
authors.lastname: Sollid
mesh_terms: D000328:Adult; D000368:Aged; D015551:Autoimmunity; D016175:B-Lymphocyte Subsets / Q000276:immunology / Q000378:metabolism; D002446:Celiac Disease / Q000097:blood / Q000188:drug therapy / Q000235:genetics / Q000276:immunology*; D060965:Clonal Evolution; D016000:Cluster Analysis; D005260:Female; D019204:GTP-Binding Proteins / Q000276:immunology; D015870:Gene Expression; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007070:Immunoglobulin A / Q000097:blood / Q000276:immunology; D007143:Immunoglobulin Heavy Chains / Q000235:genetics; D007133:Immunoglobulin Joining Region / Q000235:genetics; D007135:Immunoglobulin Variable Region / Q000235:genetics; D007156:Immunologic Memory; D007422:Intestines / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000276:immunology* / Q000378:metabolism; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases / Q000276:immunology
chemical_list: D007070:Immunoglobulin A; D007143:Immunoglobulin Heavy Chains; D007133:Immunoglobulin Joining Region; D007135:Immunoglobulin Variable Region; D000091345:Protein Glutamine gamma Glutamyltransferase 2; D011503:Transglutaminases; D019204:GTP-Binding Proteins