title: Autoantibody Profiling in a Cohort of Pediatric and Adult Patients With Autoimmune Hepatitis.
abstract: BACKGROUND
  Autoimmune hepatitis (AIH) is a rare condition characterized by the presence of autoantibodies distinctive of type 1 AIH (AIH-1) and type 2 AIH (AIH-2). The aim of this study was to evaluate the autoantibody profile in a cohort of pediatric and adult AIH patients, using both indirect immunofluorescence (IIF) and a new multiplexed line-blot assay.
  
  
  METHODS
  Sera from 63 pediatric and 53 adult AIH patients were tested for antinuclear (ANA), antismooth muscle (SMA), anti-liver kidney microsome 1 (anti-LKM1), anti-liver cytosol 1 (anti-LC1) autoantibodies using IIF methods; for anti-LKM1, anti-LC1, and soluble liver antigen/liver-pancreas (anti-SLA/LP) autoantibodies using the line-blot; for anti-F-actin autoantibodies using IIF both on VSM47 cell-line and on rat intestinal epithelial cells.
  
  
  RESULTS
  AIH-1 was the most common type of AIH in the adult cohort (73.6%), while AIH-2 was the most common AIH in the pediatric cohort (61.9%). Both in adult and pediatric AIH-2 anti-LKM1 were the prevalent autoantibodies. In pediatric AIH-2 anti-LC1 autoantibodies were more frequent than in adult AIH-2 (59 vs. 28.6%), and in 35.9% of cases they were present alone. In 17 patients anti-LC1 autoantibodies were detected only with the line-blot assay. The levels of anti-LKM1 and of anti-LC1 were not different between adult and pediatric AIH, and the overall agreement between the results obtained with the two IIF methods for F-actin detection was 98.8% (CI 95%: 94.4-99.7%).
  
  
  CONCLUSIONS
  The line-blot assay showed a higher sensitivity than IIF for anti-LC1 detection. Anti-LKM1 and anti-LC1 autoantibody levels are not different in adults and children. An almost perfect agreement between the two IIF methods for anti-F-actin detection has been observed.
authors.affiliation: Allergologia e Immunologia Clinica, A.O. "S. Maria degli Angeli", Pordenone, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Villalta
authors.affiliation: Dipartimento di Oncoematologia Pediatrica e Medicina Trasfusionale, Ospedale Bambino Gesù, Roma, Italy.
authors.forename: Elia
authors.initials: E
authors.lastname: Girolami
authors.affiliation: Laboratorio Analisi Chimico-Cliniche, Ospedali Riuniti di Bergamo, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Alessio
authors.affiliation: Laboratorio Analisi Chimico-Cliniche e Microbiologiche, ISMETT, Palermo, Italy.
authors.forename: Maria Concetta
authors.initials: MC
authors.lastname: Sorrentino
authors.affiliation: Laboratorio di Patologia Clinica, Policlinico Consorziale di Bari, Italy.
authors.forename: Marilina
authors.initials: M
authors.lastname: Tampoia
authors.affiliation: Patologia Clinica, Ospedale Buccheri La Ferla, Palermo, Italy.
authors.forename: Ignazio
authors.initials: I
authors.lastname: Brusca
authors.affiliation: Laboratorio Centrale, Ospedale Civile, Merano (BZ), Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Daves
authors.affiliation: Dipartimento Biotecnologie Mediche, Università di Siena, Italy.
authors.forename: Brunetta
authors.initials: B
authors.lastname: Porcelli
authors.affiliation: Patologia Clinica, Ospedale Cà Foncello, Treviso, Italy.
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Barberio
authors.affiliation: Allergologia e Immunologia Clinica, A.O. "S. Maria degli Angeli", Pordenone, Italy.
authors.forename: Mariaelisabetta
authors.initials: M
authors.lastname: Conte
authors.affiliation: Allergologia e Immunologia Clinica, A.O. "S. Maria degli Angeli", Pordenone, Italy.
authors.forename: Lisa
authors.initials: L
authors.lastname: Pantarotto
authors.affiliation: Patologia Clinica, Ospedale Civile, Tolmezzo (UD), Italy.
authors.forename: Nicola
authors.initials: N
authors.lastname: Bizzaro
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D001323:Autoantibodies / Q000097:blood*; D002460:Cell Line; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003710:Demography; D004847:Epithelial Cells / Q000378:metabolism; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D019693:Hepatitis, Autoimmune / Q000097:blood* / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D051381:Rats; D055815:Young Adult
chemical_list: D001323:Autoantibodies
keywords: anti-F-actin; autoantibodies; autoimmune hepatitis; indirect immunofluorescence; multiplexed line-blot; reference intervals