Hepatitis B Splice-Generated Protein Antibodies in Syrian Chronic Hepatitis B Patients: Incidence and Significance

Background: Previous studies have suggested hepatitis B splice-generated protein (HBSP), when expressed, is involved in the pathogenesis of HBV infection. Objectives: We aimed to evaluate anti-HBSP incidence and association with several HBV infection parameters in a group of Syrian chronic hepatitis B patients. Patients and Methods: Eighty treatment-naïve HBsAg-positive adult chronic hepatitis B patients sera were included in our prospective targeted study. Liver function, virological and histological tests results were obtained from patients’ medical files. Three variants of a 20-mer HBSP-derived peptide were designed based on HBV genome sequences obtained from Syrian patients sera (GenBank Accession No. JN257148-JN257217). Microtiter plate wells were coated with the synthetic peptides and used to detect anti-HBSP antibodies by an optimized indirect enzyme-linked immunosorbent assay (ELISA). Samples were considered positive when showed optical density (OD) values higher than the cut-off value for at least one peptide variant. Results: Seven out of eighty (9%) CHB patients were positive for anti-HBSP antibodies. Mean OD values were not significantly different between HBeAg-positive and -negative patients (P 0.05). OD values showed weak positive correlation with ALT and AST values (P 0.05), and weak to moderate positive correlation with liver biopsy staging ranks (P 0.05). No significant correlation was revealed with viral load values or liver biopsy grading ranks (P 0.05). Conclusions: We introduced an anti-HBSP antibodies ELISA, designed for locally circulating HBV strains. Correlation observed of Anti-HBSP with liver fibrosis staging regardless of viral replication and liver inflammation suggests anti-HBSP antibodies as possible indicator for HBV-associated liver fibrosis.