mRNA Vaccines Induce Rapid Antibody Responses in Mice

mRNA vaccines can be developed and produced quickly, making them attractive for immediate outbreak responses. Furthermore, clinical trials have demonstrated rapid protection following mRNA vaccination. We sought to investigate how quickly mRNA vaccines elicit antibody responses compared to other vaccine modalities. We first examined immune kinetics of mRNA and DNA vaccines expressing SARS-CoV-2 spike in mice. We observed rapid induction of antigen-specific binding and neutralizing antibodies by day 5 following mRNA, but not DNA, immunization. The mRNA vaccine also induced increased levels of IL-5, IL-6 and MCP-1. We then evaluated immune kinetics of an HIV-1 mRNA vaccine in comparison to DNA, protein, and rhesus adenovirus 52 (RhAd52) vaccines with the same HIV-1 envelope antigen in mice. Induction of envelope-specific antibodies was observed by day 5 following mRNA vaccination, whereas antibodies were detected by day 7-14 following DNA, protein, and RhAd52 vaccination. Eliciting rapid humoral immunity may be an advantageous property of mRNA vaccines for controlling infectious disease outbreaks.

The Functions of Hepatitis B Virus Encoding Proteins: Viral Persistence and Liver Pathogenesis

About 250 million people worldwide are chronically infected with Hepatitis B virus (HBV), contributing to a large burden on public health. Despite the existence of vaccines and antiviral drugs to prevent infection and suppress viral replication respectively, chronic hepatitis B (CHB) cure remains a remote treatment goal. The viral persistence caused by HBV is account for the chronic infection which increases the risk for developing liver cirrhosis and hepatocellular carcinoma (HCC). HBV virion utilizes various strategies to escape surveillance of host immune system therefore enhancing its replication, while the precise mechanisms involved remain elusive. Accumulating evidence suggests that the proteins encoded by HBV (hepatitis B surface antigen, hepatitis B core antigen, hepatitis B envelope antigen, HBx and polymerase) play an important role in viral persistence and liver pathogenesis. This review summarizes the major findings in functions of HBV encoding proteins, illustrating how these proteins affect hepatocytes and the immune system, which may open new venues for CHB therapies.

Hepatitis B Envelope Antigen in Children and Adults with Hepatitis B Infection in Tertiary Health Facility in North East Nigeria During the Period 2000-2015

Introduction: Worldwide, most people living with chronic HBV infection are in in low- and middle-income countries. Most of the burden of disease from HBV infection comes from infections acquired before the age of 5 years. Materials and Methods: Records of Hepatitis B surface and envelope antigen results of children and adults in Federal Teaching Hospital, Gombe between May 2000 and May 2015 were analyzed Results: 22,862 individuals were tested for Hepatitis B surface antigen. 19.5% (4456) tested positive. 24.7 % (3146) and 12.9% (1310) of males and females respectively were HBsAg positive. HBsAg Peak prevalence of 21.8% was in the age group 26-46 (2533) and the lowest prevalence in infancy (3.5%). Amongst males, the 19-25year age group had the peak prevalence of 28.6% and in females the age group 5-9 years constituted the highest (20.3%). 36% (1602/4456) of HBsAg positive children and adults were tested for HBeAg. 26.2% (420/1602) of individuals with HBsAg carriage were HBeAg. More males (307/1105) than females (113/495) were HBeAg positive but not statistically significant. (P=0.034). Prevalence of HBeAg was highest in infants (50%) and children 1-4 years (50%) age group and thereafter declined with increasing age. Females of the younger age group <1year, 1-4 years and 5-9 years and older age group, 56-65 and >65 years, compared to their male carriers of HBsAg had higher prevalence of HBeAg but these were not statistically significant. Conclusion: A fifth of HBsAg carriers were HBeAg positive and HBeAg positivity decreased with increasing age. Hepatitis B vaccination in Nigeria requires urgent strengthening. Keywords: Hepatitis, HBsAg, HBeAg Children, Adults, Nigeria.

Efficacy of 24-week Administration of Tenofovir Disoproxil Fumarate in the Management of Naïve Chronic Hepatitis B

BACKGROUND: Chronic hepatitis B (CHB) is becoming a common liver abnormality worldwide. Thus, a series of good management is needed to prevent the progression and complications of hepatitis B infection. Tenofovir disoproxil fumarate (TDF) is one of the drugs of choice that’s used for CHB management. AIM: Limited studies were found regarding the efficacy of tenofovir in dealing with CHB. Hence, the aim of this study is to determine the efficacy of TDF administration for 24 weeks in subjects with naïve CHB in Medan, Indonesia. METHODS: Retrospective study was conducted in Haji Adam Malik Hospital Medan, Indonesia, between January and December 2019. Subjects were CHB patients aged 18 years or older and were treated TDF for 24 weeks. Demographic, clinical, and CHB disease progression parameters (serum alanine aminotransferase [ALT], hepatitis B envelope antigen [HBeAg], and hepatitis B virus deoxyribonucleic acid [HBV DNA]) data were obtained. RESULTS: One hundred and twenty subjects were obtained and divided into 2 groups: HBeAg positive and HBeAg negative. Mean age of subjects was 46.5 ± 10.36 years in HBeAg positive group and 48.6 ± 10.67 years HBeAg negative group, with predominant males’ subjects in both groups (58.3% vs. 61.7%, respectively). Serum ALT normalization and undetectable serum HBV DNA were observed in more than 70% and 65% of subjects in both groups, respectively (both p < 0.001). Serum HBeAg loss was achieved in 10.8% subjects (p < 0.001). No subject showed serum HbsAg loss. CONCLUSION: Our results are consonant with current clinical guidelines and other evidence literature. For both HBeAg-positive and HBeAg-negative populations, TDF administration for 24 weeks has good efficacy in naïve CHB patients.