Immunostimulatory effects of complex GPB through increased TNF-α expression and NK cell activation

Background: Complex Great Powerful Blend (GPB) (a great powerful blend) is a hot water extract of three well-known dried fruits: goji berry, mulberry, and jujube. These fruits have been used as food for a long time, and this article sought to confirm the immunostimulatory effects of Complex GPB. Materials and Methods: To do this, in vitro study using RAW264.7 cells and in vivo using normal mice were performed. Cytokine production and NK cell activity levels were measured by enzyme-linked immunosorbent assay, real-time polymerase chain reaction (PCR), and the YAC-1 cell-killing assay. Transcription factor activation levels were also determined by western blotting analysis. Results: First, it was confirmed that Complex GPB had no cytotoxic effects on the cells and increased the production levels of tumor necrosis factor (TNF)-a in a concentration-dependent manner. Additionally, Complex GPB enhanced pro-inflammatory cytokine expressions such as TNF-a, IL-12a, and IL-1b. Western blotting analysis revealed that activation of the NF-kB and AP-1 pathways are involved. Furthermore, in vivo study confirmed that TNF-a was found to be elevated in the serum and splenocytes of mice-fed Complex GPB. Cytotoxic activation of NK cells was also increased in mice injected with Complex GPB. Conclusion: These results suggest that Complex GPB has an immune-enhancing effect, which can be used for immunomodulatory remedies.