Hepatitis B Immunoglobulin Inhibits The Secretion of HBV Via Antigen-Antibody Precipitation in The Multivesicular Body

Although the main action of human hepatitis B immunoglobulin (HBIG) of neutralizing the hepatitis B virus surface antigen (HBsAg) in the serum is known, HBIG is known to be localized in the cell. However, the effect of intracellularly located HBIG is not well elucidated due to the low purity of conventional plasma-derived HBIG (cHBIG). We attempted to clarify the mechanism of action of internalized HBIG using recombinant HBIG (lenvervimab). We used HBsAg cell lines, non-HBsAg cell lines and human HBsAg-producing hepatocytes. Autophagosome lysis pathway related proteins and Rab5, calnexin, giantin, and Rab7 were used to localize HBsAg and anti-HBs-IgG in the cytoplasm with Western blot and confocal microscopy.Intracellular anti-HBs-IgG (lenvervimab and cHBIG) transported by Fc receptor-mediated endocytosis increased the autophagosomes, but there was no change in autolysis. HBsAg and anti-HBs-IgG precipitated in the cytoplasm and co-localized in the multivesicular body. HBsAg secretion in the culture medium was decreased after lenvervimab. Simultaneously, the amount of cellular HBsAg increased in the cell lines but decreased in the human hepatocytes. Furthermore, intracellular lenvervimab was not easily washed out only in the HBsAg cell lines.Lenvervimab decreases the secretion of HBsAg, and HBsAg-antibody precipitation in the multivesicular body might play an important role.

Hepatitis B Virus (HBV) Disease

HBV disease is a significant cause of acute and chronic liver disease worldwide. Mother-to-infant transmission is the main mode of transmission to susceptible subjects, which can be prevented with HBV vaccine alone or in combination with hepatitis B immunoglobulin. This intervention markedly reduces the number of new HBsAg carriers. For subjects not responding to current HBV vaccines as reflected by an inadequate anti-HBs titer, future generation vaccines incorporating additional vaccine components such as preS1 and preS2 may improve the efficacy of protective antibody production. Apart from preventative vaccines, future therapeutic vaccines along with current anti-HBV treatment strategies might enhance the rate of functional cures as indicated by the loss of HBsAg.

Dried blood spot (DBS) testing for infants born to mothers with hepatitis B

Hepatitis B is a vaccine preventable disease that can lead to serious complications such as cirrhosis, liver failure and death. Globally, the most common route of HBV acquisition is via perinatal transmission: from mother to baby at the time of birth. Pregnant women in the UK are tested for hepatitis B infection to reduce the risk of perinatal transmission by ensuring early identification, treatment and management of any pregnant women, and their unborn babies, who test positive. If infants born to women with hepatitis B infection receive post-exposure vaccination (+/− hepatitis B immunoglobulin) within the recommended timescales, 90% of them will be protected from chronic persistent infection and serious complications such as cirrhosis, liver failure and death. However, HBV infection in infants can be asymptomatic so testing them at 1 year old is essential to detect whether they are infected and require treatment. Public Health England provide a national dried blood spot (DBS) testing service for infants born to mothers with hepatitis B infection during pregnancy. Practice nurses can play a key role in this process, helping to protect infants.

Effectiveness of recombinant hepatitis B vaccine with/without the passive hepatitis B immunoglobulin vaccine in babies whose mothers are hepatitis B surface antigen positive in a private missionary hospital

Background: Hepatitis B infection is a potentially life-threatening liver infection. The burden is more in the less developed countries. Vaccination is the most cost-effective way to control hepatitis B virus (HBV) infection and its chronic complications globally. Active-passive immunoprophylaxis using hepatitis B immunoglobulin combined with recombinant hepatitis B vaccine is recommended for infants of women with chronic HBV infection. This study aimed to determine the effectiveness of the hepatitis B recombinant vaccine alone or combined with hepatitis B immunoglobulin.Methods: The study was a prospective longitudinal study. Patients were selected using a convenient sampling technique. The study spanned between 1 January 2017 and 31 December 2018. Data analysis was with SPSS version 21.Results: The unit recorded 1690 deliveries during the recruitment period, 70 eligible patients were recruited thus giving an incidence of 4.1%. 74.3% of the recruited patients were HBeAg negative while 25.7% were HBeAg positive. 52.9% of the babies had only recombinant HB recombinant vaccine while 47.1% had combined hepatitis B immunoglobulin and the recombinant vaccine at birth. The HBeAg status of mothers played a significant factor in the HBsAg positivity of babies two months after the completion of immunoprophylaxis against HBV.Conclusions: Giving recombinant HBV vaccine in combination with the HBV immunoglobulin is the standard practice, this may not always be so based on the findings from this study. However, the population studied is too small to make a categorical statement thus a larger population needs to be studied.