Hamzeh Sarvnaz; Sahar Asadi-Asadabad; Mohammad Mehdi Amiri; Mojgan Ghaedi; Ulrike Protzer; Mahmood Jeddi-Tehrani; Forough Golsaz-Shirazi; Fazel Shokri
Abstract
Background: Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection.Objective: This study ...
Read More
Background: Human polyclonal plasma-derived hepatitis B immunoglobulin (HBIG) is currently used for immunoprophylaxis of HBV infection. The development of virus-neutralizing monoclonal antibodies (MAbs) requires the use of optimized cell culture systems supporting HBV infection.Objective: This study aims to optimize the hepatitis B virus infectivity of NTCP-reconstituted HepG2 (HepG2-NTCP) cells to establish an efficient system to evaluate the HBV-neutralizing effect of anti-HBs MAbs.Methods: Serum-derived HBV (sHBV) and cell culture-derived HBV (ccHBV) were simultaneously used for the optimization of HBV infection in HepG2-NTCP cells by applying different modifications.Results: Our results for the first time showed that in addition to human serum, monkey serum could significantly improve ccHBV infection, while fetal and adult bovine serum as well as duck and sheep serum did not have a promotive effect. In addition, sHBV and ccHBV infectivity are largely similar except that adding 5% of PEG, which is commonly used to improve in vitro infection of ccHBV, significantly reduced sHBV infection. We showed that a combination of spinoculation, trypsinization, and also adding human or monkey serum to HBV inoculum could significantly improve the permissivity of HepG2-NTCP cells to HBV infection compared with individual strategies. All anti-HBs MAbs were able to successfully neutralize both ccHBV and sHBV infection in our optimized in vitro system.Conclusion: Our study suggests different strategies for improving ccHBV and sHBV infection in HepG2-NTCP cells. This cell culture-based system allows assessment of HBV neutralizing MAbs and may also prove to be valuable for the analysis of other HBV neutralizing therapeutics.
Ali Akbar Amirzargar; Nilufar Mohseni; Mohammad Ali Shokrgozar; Zohreh Arjang; Nahid Ahmadi; Manijeh Yousefi Behzadi; Amir Amanzadeh; Fazel Shokri
Abstract
Background: Different studies have demonstrated that a small proportion of healthy individuals receiving the hepatitis B (HB) vaccine do not produce protective levels of anti-HB antibody, a phenomenon which could be linked to certain human leukocyte an-tigen (HLA) class-II alleles or haplotypes. Objectives: ...
Read More
Background: Different studies have demonstrated that a small proportion of healthy individuals receiving the hepatitis B (HB) vaccine do not produce protective levels of anti-HB antibody, a phenomenon which could be linked to certain human leukocyte an-tigen (HLA) class-II alleles or haplotypes. Objectives: The present study was under-taken to determine the frequency of HLA class-II alleles in Iranian healthy adult re-sponders and non-responders to HB vaccine. Methods: Twelve non-responders (anti-HBs antibody<10 IU/L) and 46 responders (anti-HBs antibody>100 IU/L) were tissue typed for HLA class-II. HLA-DRB1, DQB1 and DQA1 alleles were determined using polymerase chain reaction based on sequence specific primers (PCR-SSP) technique. Accessibility to excess amount of genomic DNA was possible using Epstein-Barr virus (EBV)-transformed B-cells established from all vaccinees. Results: Our results demon-strated increased frequencies of HLA- DRB1*07, DRB1*03, DRB1*04, DQB1*0201, DQA1*0201 alleles and HLA- DRB1*07/DQB1*0201/DQA1*0201 and DRB1*04/DQB1*0302/DQA1*03011 haplotypes in the non-responder group. Com-parison between responders and non-responders revealed only a significant difference for DQB1*0201 allele (p<0.05). Conclusion: These findings confirm the association of certain HLA alleles and haplotypes with the lack of antibody response to HB vaccine in an Iranian population.
