title: Expression of activation-induced cytidine deaminase gene in B lymphocytes of patients with common variable immunodeficiency.
abstract: OBJECTIVE
  Common variable immunodeficiency (CVID) is a heterogeneous disorder characterized by reduced serum level of IgG, IgA or IgM and recurrent bacterial infections. Class switch recombination (CSR) as a critical process in immunoglobulin production is defective in a group of CVID patients. Activation-induced cytidine deaminase (AID) protein is an important molecule involving CSR process. The aim of this study was to investigate the AID gene mRNA production in a group of CVID patients indicating possible role of this molecule in this disorder.
  
  
  METHODS
  Peripheral blood mononuclear cells (PBMC) of 29 CVID patients and 21 healthy controls were isolated and stimulated by CD40L and IL-4 to induce AID gene expression. After 5 days AID gene mRNA production was investigated by real time polymerase chain reaction.
  
  
  RESULTS
  AID gene was expressed in all of the studied patients. However the mean density of extracted AID mRNA showed higher level in CVID patients (230.95±103.04 ng/ml) rather than controls (210.00±44.72 ng/ml; P=0.5). CVID cases with lower level of AID had decreased total level of IgE (P=0.04) and stimulated IgE production (P=0.02); while cases with increased level of AID presented higher level of IgA (P=0.04) and numbers of B cells (P=0.02) and autoimmune disease (P=0.02).
  
  
  CONCLUSIONS
  Different levels of AID gene expression may have important roles in dysregulation of immune system and final clinical presentation in CVID patients. Therefore investigating the expression of AID gene can help in classifying CVID patients.
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Hassan
authors.initials: H
authors.lastname: Abolhassani
authors.affiliation: Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Amir Salek
authors.initials: AS
authors.lastname: Farrokhi
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Shabnam
authors.initials: S
authors.lastname: Pourhamdi
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Payam
authors.initials: P
authors.lastname: Mohammadinejad
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Bamdad
authors.initials: B
authors.lastname: Sadeghi
authors.affiliation: Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
authors.forename: Seyed-Mohammad
authors.initials: SM
authors.lastname: Moazzeni
authors.affiliation: Research Center for Immunodeficiencies, Children's Medical Center, Pediatrics Center of Excellence, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Asghar
authors.initials: A
authors.lastname: Aghamohammadi
keywords: AICDA Protein; Activation-Induced Cytidine Deaminase; Class Switching; Common Variable Immunodeficiency