title: Cytometry by time-of-flight immunophenotyping identifies a blood Sjögren's signature correlating with disease activity and glandular inflammation.
abstract: Mass cytometry has recently emerged as a promising tool for clinical research. However, few studies have demonstrated its benefit for patient stratification and biomarker identification. Primary Sjögren's syndrome (pSS) is a prototype of chronic autoimmune disease, the pathogenesis of which remains unclear and for which treatment does not exist.
  
  
  
  This observational case-control study was designed to discover new cellular biomarkers and therapeutic targets in patients with pSS.
  
  
  
  Forty-nine patients with pSS and 45 control subjects were enrolled for clinical evaluation and mass cytometry quantification of 34 protein markers in blood. For a third of these subjects, matched labial salivary gland biopsy specimens were also analyzed by mass cytometry and immunohistochemistry.
  
  
  
  In salivary gland biopsy specimens from patients with pSS, we identified a high number of activated CD8(+) T cells, terminally differentiated plasma cells, and activated epithelial cells, pointing to new pathogenic mechanisms for future clinical intervention. In blood, we identified a 6-cell disease signature defined by decreased numbers of CD4 and memory B lymphocytes, decreased plasmacytoid dendritic cell numbers, and increased representation of activated CD4 and CD8 T cells and plasmablasts. These blood cellular components correlated with clinical parameters and, when taken together, clustered patients into subsets with distinct disease activity and glandular inflammation.
  
  
  
  This first application of mass cytometry to a well-stratified clinical cohort and small biopsy tissues establishes the benefits of such an approach for the discovery of new biomarkers and therapeutic targets. Similar high-dimensional immunophenotyping strategies could be implemented in longitudinal and interventional clinical settings in this and other disease areas.
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass. Electronic address: michael.mingueneau@biogen.com.
authors.forename: Michael
authors.initials: M
authors.lastname: Mingueneau
authors.affiliation: Faculté de Médecine, Université Paris Sud, Le Kremlin-Bicêtre, France; INSERM, U1184, Center for immunology of viral infections and autoimmune diseases, Le Kremlin-Bicêtre, France.
authors.forename: Saida
authors.initials: S
authors.lastname: Boudaoud
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Scott
authors.initials: S
authors.lastname: Haskett
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Taylor L
authors.initials: TL
authors.lastname: Reynolds
authors.affiliation: Faculté de Médecine, Université Paris Sud, Le Kremlin-Bicêtre, France; INSERM, U1184, Center for immunology of viral infections and autoimmune diseases, Le Kremlin-Bicêtre, France; Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Sud, Le Kremlin-Bicêtre, France.
authors.forename: Gaetane
authors.initials: G
authors.lastname: Nocturne
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Norton
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Xueli
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Myrtha
authors.initials: M
authors.lastname: Constant
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Daniel
authors.initials: D
authors.lastname: Park
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Wenting
authors.initials: W
authors.lastname: Wang
authors.affiliation: Faculté de Médecine, Université Paris Sud, Le Kremlin-Bicêtre, France; INSERM, U1184, Center for immunology of viral infections and autoimmune diseases, Le Kremlin-Bicêtre, France; Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Sud, Le Kremlin-Bicêtre, France.
authors.forename: Thierry
authors.initials: T
authors.lastname: Lazure
authors.affiliation: Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Sud, Le Kremlin-Bicêtre, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Le Pajolec
authors.affiliation: Immunology Research, Biogen, Cambridge, Mass.
authors.forename: Ayla
authors.initials: A
authors.lastname: Ergun
authors.affiliation: Faculté de Médecine, Université Paris Sud, Le Kremlin-Bicêtre, France; INSERM, U1184, Center for immunology of viral infections and autoimmune diseases, Le Kremlin-Bicêtre, France; Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Sud, Le Kremlin-Bicêtre, France.
authors.forename: Xavier
authors.initials: X
authors.lastname: Mariette
mesh_terms: D000328:Adult; D015415:Biomarkers; D001706:Biopsy; D018414:CD8-Positive T-Lymphocytes; D016000:Cluster Analysis; D019295:Computational Biology / Q000379:methods; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping / Q000379:methods; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells; D015203:Reproducibility of Results; D012469:Salivary Glands / Q000378:metabolism* / Q000473:pathology*; D012470:Salivary Glands, Minor / Q000378:metabolism / Q000473:pathology; D012859:Sjogren's Syndrome / Q000175:diagnosis*
chemical_list: D015415:Biomarkers
keywords: Sjögren's syndrome; autoimmunity; biomarker discovery; cytometry by time-of-flight; immunophenotyping; mass cytometry; patient stratification; therapeutic target