Lentinan relieves hepatitis B surface antigen induced functional impairment of monocytes/macrophages

Abstract

Purpose: To investigate the efficacy of lentinan in relieving hepatitis B surface antigen (HBsAg)-induced functional impairment of monocytes/macrophages. Methods: Monocytic cell line THP-1 was incubated with lentinan and HBsAg for 24 h and then stimulated with LPS (Lipopolysaccharide). The expression levels of interleukin-1β (IL-1β), IL-12 and tumour necrosis factor-α (TNF-α) were measured by enzyme-linked immunosorbent (ELISA) assays and quantitative reverse transcriptase-PCR (q-PCR). Protein levels of IkB-α, phospho-ERK, and phospho-p38 were measured by western blotting. Results: THP-1 cells treated with lentinan and HBsAg showed higher IL-1β, IL-12, and TNF-α levels than cells treated with HBsAg alone. The underlying mechanisms were associated with NF-kB and MAPK signal pathways. Decreased expression of IkB-α and phospho-ERK and increased expression of phospho-JNK and phospho-p38 were observed in cells treated with lentinan and HBsAg when compared with cells treated with HBsAg alone (p < 0.001). THP-1 cells incubated with 500 μg/mL lentinan secreted lower levels of cytokines than did control cells after LPS stimulation, suggesting an anti-inflammatory effect for lentinan. Conclusion: Lentinan shows both pro- and anti-inflammatory functions and may be a promising candidate for hepatitis B virus (HBV) treatment.