title: Memory B cell subsets and plasmablasts are lower in early than in long-standing rheumatoid arthritis.
abstract: BACKGROUND
  Alterations of B cell subset distribution have been described in the peripheral blood (PB) of rheumatoid arthritis (RA) patients, but no data are available on differences between the onset and the established phases of the disease. The purpose of the study was to clarify whether a peculiar distribution of B cell subsets characterizes RA onset, thus leading to a more favorable clinical response to treatment, and to evaluate the possible association of a particular B cell subpopulation with response to therapy.
  
  
  RESULTS
  122 RA patients were enrolled: 25 had symptom duration less than 3 months and were defined as having "very early RA" (VERA), and 43 had symptom duration from more than 3 months up to one year (early-RA: ERA). The other 54 RA patients had long-standing RA (LSRA). At baseline and at 6-month follow-up visit peripheral blood samples were collected and analyzed by flow cytometry for the distribution of circulating B cell subsets by staining with surface markers CD45, CD19, CD38, CD27 and IgD and intracellular marker ZAP70.VERA and ERA patients showed higher percentages and absolute counts of circulating antigen inexperienced naïve B cells (IgD + CD27-) and lower percentages and absolute numbers of double negative (IgD-CD27-) memory B cells and plasmablasts (CD38 + CD27+) compared to LSRA patients. At the multivariate analysis, a higher frequency of naïve B cells (IgD + CD27-) at baseline arose as significant predictor of CDAI remission, together with "having VERA disease" and a low disease activity at baseline.
  
  
  CONCLUSIONS
  The onset of RA is characterized by higher percentages and absolute numbers of naïve B cells and lower numbers of plasmablasts and double negative memory B cells compared to established RA. Naïve B cells could represent a promising biomarker of outcome.
authors.forename: Anna Laura
authors.initials: AL
authors.lastname: Fedele
authors.forename: Barbara
authors.initials: B
authors.lastname: Tolusso
authors.forename: Elisa
authors.initials: E
authors.lastname: Gremese
authors.forename: Silvia Laura
authors.initials: SL
authors.lastname: Bosello
authors.forename: Angela
authors.initials: A
authors.lastname: Carbonella
authors.forename: Silvia
authors.initials: S
authors.lastname: Canestri
authors.affiliation: Division of Rheumatology, Institute of Rheumatology and Affine Sciences, Catholic University of the Sacred Heart, Via Moscati 31, Rome, 00168, Italy. gf.ferraccioli@rm.unicatt.it.
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Ferraccioli
mesh_terms: D017668:Age of Onset; D015703:Antigens, CD / Q000378:metabolism; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000276:immunology* / Q000473:pathology; D053264:B-Cell Activating Factor / Q000097:blood; D016175:B-Lymphocyte Subsets / Q000276:immunology* / Q000473:pathology; D003710:Demography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007072:Immunoglobulin D / Q000276:immunology; D007156:Immunologic Memory; D007249:Inflammation / Q000473:pathology; D015850:Interleukin-6 / Q000097:blood; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000276:immunology* / Q000473:pathology; D013997:Time Factors; D051746:ZAP-70 Protein-Tyrosine Kinase / Q000378:metabolism
chemical_list: D015703:Antigens, CD; D053264:B-Cell Activating Factor; D007072:Immunoglobulin D; D015850:Interleukin-6; C505719:TNFSF13B protein, human; D051746:ZAP-70 Protein-Tyrosine Kinase; C497261:ZAP70 protein, human