title: Protein microarrays identify disease-specific anti-cytokine autoantibody profiles in the landscape of immunodeficiency.
abstract: BACKGROUND
  Anti-cytokine autoantibodies (ACAAs) are pathogenic in a handful of rare immunodeficiencies. However, the prevalence and significance of other ACAAs across immunodeficiencies have not yet been described.
  
  
  OBJECTIVE
  We profiled ACAAs in a diverse cohort of serum samples from patients with immunodeficiency and assessed the sensitivity and specificity of protein microarrays for ACAA identification and discovery.
  
  
  METHODS
  Highly multiplexed protein microarrays were designed and fabricated. Blinded serum samples from a cohort of 58 immunodeficiency patients and healthy control subjects were used to probe microarrays. Unsupervised hierarchical clustering was used to identify clusters of reactivity, and after unblinding, significance analysis of microarrays was used to identify disease-specific autoantibodies. A bead-based assay was used to validate protein microarray results. Blocking activity of serum containing ACAAs was measured in vitro.
  
  
  RESULTS
  Protein microarrays were highly sensitive and specific for the detection of ACAAs in patients with autoimmune polyendocrine syndrome type I and pulmonary alveolar proteinosis, detecting ACAA levels consistent with those reported in the published literature. Protein microarray results were validated by using an independent bead-based assay. To confirm the functional significance of these ACAAs, we tested and confirmed the blocking activity of select ACAAs in vitro.
  
  
  CONCLUSIONS
  Protein microarrays are a powerful tool for ACAA detection and discovery, and they hold promise as a diagnostic for the evaluation and monitoring of clinical immunodeficiency.
authors.affiliation: Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, Calif. Electronic address: JakeRos@stanford.edu.
authors.forename: Jacob M
authors.initials: JM
authors.lastname: Rosenberg
authors.affiliation: Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, Calif.
authors.forename: Jordan V
authors.initials: JV
authors.lastname: Price
authors.affiliation: Department of Clinical Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, United Kingdom; Laboratorio de Inmunologia, UNAM, FES-Cuautitlan, Cuautitlán Izcalli, Mexico.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Barcenas-Morales
authors.affiliation: Department of Clinical Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, United Kingdom.
authors.forename: Lourdes
authors.initials: L
authors.lastname: Ceron-Gutierrez
authors.affiliation: Department of Clinical Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, United Kingdom.
authors.forename: Sophie
authors.initials: S
authors.lastname: Davies
authors.affiliation: Department of Clinical Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, United Kingdom.
authors.forename: Dinakantha S
authors.initials: DS
authors.lastname: Kumararatne
authors.affiliation: Department of Clinical Biochemistry and Immunology, Addenbrooke's Hospital, Cambridge, United Kingdom; National Institute for Health Research (NIHR), Cambridge Biomedical Research Centre, Cambridge, United Kingdom.
authors.forename: Rainer
authors.initials: R
authors.lastname: Döffinger
authors.affiliation: Department of Medicine, Division of Immunology and Rheumatology, Stanford University School of Medicine, Stanford, Calif; Institute for Immunity, Transplantation, and Infection, Stanford University School of Medicine, Stanford, Calif. Electronic address: PJUtz@stanford.edu.
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Utz
mesh_terms: D001323:Autoantibodies / Q000097:blood*; D016207:Cytokines / Q000276:immunology*; D006801:Humans; D007153:Immunologic Deficiency Syndromes / Q000097:blood / Q000276:immunology*; D040081:Protein Array Analysis
chemical_list: D001323:Autoantibodies; D016207:Cytokines
keywords: Anti-cytokine autoantibodies; autoimmune polyendocrine syndrome type I; immunodeficiency; protein microarray; pulmonary alveolar proteinosis; thymoma