title: Assessment of CXCL12 (SDF-1α) polymorphisms and its serum level in posttransfusion occult HBV-infected patients in Southeastern Iran.
abstract: BACKGROUND
  Occult hepatitis B infection (OBI) is defined as a form of hepatitis in which, despite absence of detectable HBsAg, HBV-DNA is present in peripheral blood of patients. The main aim of this study was to determine an association between polymorphisms in +801 of CXCL12 (SDF-1α) and its serum level in OBI patients.
  
  
  METHODS
  In this experimental study, plasma samples of 3700 blood donors were tested for HBsAg and anti-HBc by ELISA. The HBsAg(-)/anti-HBc(+) samples were selected and screened for HBV-DNA by PCR. HBV-DNA positive samples assigned as OBI cases and PCR-RFLP techniques were performed to examine the CXCL12 (SDF-1α) polymorphisms. The serum level of CXCL12 (SDF-1α) was also analyzed by ELISA.
  
  
  RESULTS
  Of 3700 blood samples, 352 (9.5%) were HBsAg/anti-HBc(+) and HBV-DNA was detected in 57/352 (16.1%) of HBsAg(-)/anti-HBc(+) samples. Our results showed a significant difference in genotypes and alleles of +801 region of CXCL12 (SDF-1α). However, the serum level of CXCL12 (SDF-1α) was decreased in OBI patients but was not significant. Our results also showed that the alleles of +801 region of CXCL12 (SDF-1α) were also not associated with serum level of the chemokine.
  
  
  CONCLUSIONS
  The polymorphisms in +801 region of CXCL12 (SDF-1α) are possibly related to OBI.
authors.affiliation: Molecular Medicine Research Center, Rafsanjan, Iran. ghassanshahi@gmail.com
authors.forename: Gholamhossein
authors.initials: G
authors.lastname: Hassanshahi
authors.forename: Mohammad Kazemi
authors.initials: MK
authors.lastname: Arababadi
authors.forename: Hossein
authors.initials: H
authors.lastname: Khoramdelazad
authors.forename: Narges
authors.initials: N
authors.lastname: Yaghini
authors.forename: Ebrahim Rezazadeh
authors.initials: ER
authors.lastname: Zarandi
mesh_terms: D054377:Chemokine CXCL12 / Q000097:blood / Q000235:genetics*; D004797:Enzyme-Linked Immunosorbent Assay; D006509:Hepatitis B / Q000235:genetics*; D006801:Humans; D007492:Iran; D011110:Polymorphism, Genetic; D065227:Transfusion Reaction
chemical_list: C515255:CXCL12 protein, human; D054377:Chemokine CXCL12