title: T-cell activation discriminates subclasses of symptomatic primary humoral immunodeficiency diseases in adults.
abstract: BACKGROUND
  Symptomatic Primary Humoral Immunodeficiency Diseases (PHID) constitute a highly heterogeneous group of diseases characterized by a shared hypogammaglobulinemia, resulting in increased risk of recurrent or severe infections. Associations have been described with a variety of immunological abnormalities involving B and T-cell differentiation, T-cell activation and innate immunity. However, PHID discrimination remains based on B-lymphocyte abnormalities and other components of the immune system have not been sufficiently taken into account. We carried out unsupervised and supervised methods for classification in a cohort of 81 symptomatic PHID patients to evaluate the relative importance of 23 immunological parameters and to select relevant markers that may be useful for diagnosis and prognosis.
  
  
  RESULTS
  We identified five groups of patients, among which the percentage of PHID complications varied substantially. Combining the set of markers involved in PHID supported the existence of two distinct mechanisms associated with complications. Switched memory B-cell attrition and CD8+ HLA-DR + activated T-cell increase were the prominent abnormalities observed in PHID complications. Furthermore, in a subgroup of 57 patients with common variable immunodeficiency, the classification that added CD8+ HLA-DR + to the consensual EUROclass classification was better than the EUROclass model in predicting complications.
  
  
  CONCLUSIONS
  These results highlight the importance of T-cell activation that may improve discrimination of PHID patients in specific subgroups and help to identify patients with different clinical outcomes.
authors.forename: Marie-Quitterie
authors.initials: MQ
authors.lastname: Picat
authors.affiliation: INSERM, ISPED, Centre INSERM U897-Epidemiologie-Biostatistique, Bordeaux F-33076, France. rodolphe.thiebaut@isped.u-bordeaux2.fr.
authors.forename: Rodolphe
authors.initials: R
authors.lastname: Thiébaut
authors.forename: François
authors.initials: F
authors.lastname: Lifermann
authors.forename: Xavier
authors.initials: X
authors.lastname: Delbrel
authors.forename: Daniel
authors.initials: D
authors.lastname: Adoue
authors.forename: Linda
authors.initials: L
authors.lastname: Wittkop
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Fauchais
authors.forename: Patrick
authors.initials: P
authors.lastname: Rispal
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Moreau
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Viallard
mesh_terms: D000328:Adult; D001402:B-Lymphocytes / Q000276:immunology / Q000378:metabolism; D015415:Biomarkers; D016000:Cluster Analysis; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007113:Immunity, Innate; D007132:Immunoglobulin Isotypes / Q000097:blood / Q000276:immunology; D007153:Immunologic Deficiency Syndromes / Q000175:diagnosis / Q000276:immunology*; D007694:Killer Cells, Natural / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology*; D008297:Male; D008875:Middle Aged; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000378:metabolism; D012680:Sensitivity and Specificity; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology / Q000378:metabolism
chemical_list: D015415:Biomarkers; D007132:Immunoglobulin Isotypes; D016692:Receptors, Antigen, T-Cell, gamma-delta