Assessment of CXCL12 (SDF-1α) Polymorphisms and Its Serum Level in Posttransfusion Occult HBV-infected Patients in Southeastern Iran

BackgroundOccult 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.MethodsIn 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.ResultsOf 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.ConclusionsThe polymorphisms in +801 region of CXCL12 (SDF-1α) are possibly related to OBI.