# Investigation of the Hepatitis-B Vaccine’s Immune Response in a Non-Alcoholic Fatty Liver Disease Mouse Model

## TL;DR

This study examined how a hepatitis B vaccine affects the immune system in mice with non-alcoholic fatty liver disease, finding that high-dose vaccination does not improve vaccine response and may worsen liver damage.

## Contribution

The study is the first to compare standard and high-dose HBV vaccination protocols in a mouse model of NAFLD, revealing no efficacy gain from high doses.

## Key findings

- High-dose HBV vaccination in NAFLD mice did not improve anti-HB titers or immune cell markers compared to standard doses.
- Mice with NAFLD showed altered immune parameters, including negative correlations between anti-HB titers and T helper cells.
- High-dose vaccination protocols were associated with increased hepatocyte ballooning in NAFLD mice.

## Abstract

This study aimed to investigate the immunogenicity of the hepatitis B virus (HBV) vaccine by applying a normal and high-dose hepatitis B virus vaccination program in the mice modeling of non-alcoholic fatty liver disease (NAFLD). NAFLD was induced in mouse livers via diet. At the 10-week mark, both groups were divided into 3 subgroups. While the standard dose vaccination program was applied on days 0, 7, and 21, two high-dose programs were applied: one was applied on days 0 and 7, and the other was applied on days 0, 7, and 21. All mice were euthanized. Blood samples from anti-HB titers; T follicular helper, T follicular regulatory, CD27+, and CD38+ cells; and the liver, spleen, and thymus were taken for histopathologic evaluation. NAFLD subgroups receiving high doses showed higher hepatocyte ballooning scores than normal-dose subgroup. There were differences in CD27+ and CD27+CD38+ cells in animals fed on different diets, without any differences or interactions in terms of vaccine protocols. In the NAFLD group, a negative correlation was observed between anti-HB titers and T helper and CD27+ cells, while a positive correlation was observed with CD38+ cells. NAFLD induced changes in immune parameters in mice, but there was no difference in vaccine efficacy among the applied vaccine protocols. Based on this study’s results, high-dose vaccination protocols are not recommended in cases of NAFLD, as they do not enhance efficacy and may lead to increased liver damage.