title: Non-association of IL-12 +1188 and IFN-γ +874 polymorphisms with cytokines serum level in occult HBV infected patients.
abstract: OBJECTIVE
  Occult hepatitis B infection (OBI) is identified as a form of hepatitis in which despite the absence of detectable HBsAg, HBV-DNA is observed in peripheral blood of patients. The main aim of this study has been to investigate the association between polymorphisms in +874 of IFN-γ and +1188 of IL-12 with their serum level in patients suffering from OBI.
  
  
  METHODS
  In this experimental study, plasma samples of 3700 blood donors were tested for the presence of hepatitis B surface antigen (HBsAg) and anti-HBc by ELISA. The HBsAg-/anti-HBc+ samples were selected and screened for HBV-DNA by PCR. HBV-DNA positive samples were assigned as OBI cases and ARMS-PCR techniques were performed to examine the two known polymorphisms within IL-12 and IFN-γ. In addition, the serum levels of IL-12 and IFN-γ were also determined by ELISA.
  
  
  RESULTS
  Results of this study demonstrated that, 352 (9.5%) out of 3700 blood samples were HBsAg-/anti-HBc+ and HBV-DNA was detected in 57/352 (16.1%) of HBsAg-/anti-HBc+ samples. Our results showed that groups showed significant difference in CC allele of +1188 region of IL-12 and no difference was observed in the other evaluated genes. Our results also showed that the alleles of +1188 region of IL-12 and alleles of +874 of IFN-γ were also not associated with serum level of cytokines.
  
  
  CONCLUSIONS
  According to the results of this study, it may be concluded that the polymorphisms in +1188 region of IL-12 and +874 region of IFN-γ would not affect the expression of both cytokines at serum level in OBI patients.
authors.affiliation: Department of Microbiology, Hematology and Immunology, Faculty of Medicine, Rafsanjan University of Medical Sciences, Rafsanjan, Iran. kazemi24@yahoo.com
authors.forename: Mohammad K
authors.initials: MK
authors.lastname: Arababadi
authors.forename: Ali A
authors.initials: AA
authors.lastname: Pourfathollah
authors.forename: Abdollah
authors.initials: A
authors.lastname: Jafarzadeh
authors.forename: Gholamhossein
authors.initials: G
authors.lastname: Hassanshahi
authors.forename: Saeed
authors.initials: S
authors.lastname: Daneshmandi
authors.forename: Ali
authors.initials: A
authors.lastname: Shamsizadeh
authors.forename: Derek
authors.initials: D
authors.lastname: Kennedy
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D006509:Hepatitis B / Q000097:blood* / Q000235:genetics* / Q000276:immunology; D006514:Hepatitis B Surface Antigens / Q000097:blood; D006801:Humans; D007111:Immunity, Cellular / Q000235:genetics; D007371:Interferon-gamma / Q000097:blood* / Q000235:genetics*; D018664:Interleukin-12 / Q000097:blood* / Q000235:genetics*; D008297:Male; D011110:Polymorphism, Genetic; D055815:Young Adult
chemical_list: D006514:Hepatitis B Surface Antigens; D018664:Interleukin-12; D007371:Interferon-gamma