by the polymerised polyphenols in a dose-dependent manner. Taken together, these results clearly Abmole PF-04691502 demonstrate that the polymerised polyphenols exhibit immunoenhancing activity against murine splenocytes, and that polymerisation is required for these activities. We then focused on the production of IFN-c and GM-CSF as indicators of the bioactivity of polymerised polyphenols. In case of mitogenic activity of lignin, previous reports have indicated that T lymphocytes are the primary target for the DNA synthesis activity of lignin. To investigate the underlying mechanisms of the effects of polymerised polyphenols on IFN-c and GM-CSF production from murine splenocytes, we examined the effect of polymerised polyphenols on CD3e + T cell-deficient splenocytes. Figure 3 shows that IFN-c and GM-CSF production induced by polymerised polyphenols strongly decreased in the absence of these T cells, suggesting that the T cell population is crucial for IFN-c and GM-CSF production induced by polymerised polyphenols. On the basis of the above-described results, we focused our attention on the representative T cell surface receptors, namely, CD4 and CD8. We next examined the effects of neutralising mAb against CD4 and CD8 with respect to IFN-c and GM-CSF production in C57BL/Publications Using Abomle MG132 6-derived splenocytes. Our results show IFN-c and GM-CSF production induced by pCA, pFA, and pCoA was significantly suppressed by the pre-treatment of anti-CD4 mAb, but not anti-CD8a mAb, indicating that IFN-c and GMCSF production in murine splenocytes by polymerised polyphenols might be modulated by CD4. We also investigated the capacity of polymerised polyphenols to bind to the murine CD4 by an ELISA-like assay and FACS. As shown in Figure 5A, immobilised polymerised polyphenols significantly increased the absorbance when reacted with CD4; however, non-polymerised polyphenols showed no effect. On the other hand, immobilised polymerised polyphenols did not bind to soluble CD8a protein. To confirm that the abovementioned action of polymerised polyphenols was not due to the differences in their abilities to bind the ELISA plate, a reverse experiment in which a competitive ELISA assay was performed using solid-phase CD4 and anti-mouse CD4 mAb. Anti-CD4 mAb binding to solid-phase CD4 protein was inhibited by polymerised polyphenols in a dose-dependent manner. Comparatively, monomers did not interfere with the binding of anti-CD4 mAb to immobilised CD4. In addition, polyphenols did not interfere with the binding of anti-CD8a mAb to immobilised CD8a. Furthermore, the binding capacity of polymerised polyphenols to cell surface CD4 was examined.