Hepatic Macrophages in Chronic Hepatitis B: Balancing Immunity and Pathology

Area of Science:

• Immunology
• Hepatology
• Virology

Background:

• Chronic hepatitis B (HBV) infection is a major global health concern, leading to liver fibrosis, cirrhosis, and hepatocellular carcinoma (HCC).
• Host immune responses, particularly macrophage activity, are key drivers of liver injury in HBV infection, rather than direct viral damage.
• Macrophages, including Kupffer cells in the liver, exhibit dual roles, contributing to both antiviral defense and disease exacerbation.

Purpose of the Study:

• To review the central role of macrophages in chronic HBV infection.
• To explore emerging therapeutic strategies targeting macrophage polarization and the hepatic microenvironment.

Main Methods:

• Literature review focusing on the immunomodulatory effects of HBV on macrophages.
• Analysis of cytokines like Interleukin-10 (IL-10) and Transforming growth factor-beta (TGF-β) in HBV-associated fibrogenesis.
• Examination of therapeutic approaches including Toll-like receptor (TLR) agonists and immune checkpoint inhibitors.

Main Results:

• HBV infection promotes a M2-like, immunosuppressive macrophage phenotype, fostering viral persistence and liver fibrosis.
• Key cytokines (IL-10, TGF-β) secreted by M2-like macrophages contribute to disease progression.
• Various therapeutic strategies targeting macrophage polarization are under investigation.

Conclusions:

• Modulating macrophage polarization and function is a promising therapeutic avenue for chronic HBV infection.
• Addressing macrophage heterogeneity and the immunosuppressive liver microenvironment is crucial for effective treatment.
• Targeting macrophages can help restore immune balance and mitigate liver injury in HBV patients.