Protective Effects of Poll Gland Secretion on Immunosuppressed and S180 Tumour-Bearing Mice

The poll gland secretions (PGS) have been used traditionally for the treatment and prevention of many diseases for centuries in Inner Mongolia (China) and Mongolia. The present study was performed to evaluate the immunostimulatory activities and anti-tumour effects of PGS in vivo and in vitro. The concentration of TNF-α, IL-2, IL-6, IgG and IgM in the serum of experimental animals were measured by an enzyme-linked immunosorbent assay (ELISA) following the manufacturer's protocols and the spleen index and thymus index were calculated using the gravimetric method. The phagocytic activity of the macrophage monocytes was evaluated by a carbon clearance assay and the effect of PGS on the growth of S180 cells in vitro was examined by the determination of the IC50 of PGS. A moderate to high dose of PGS can elevate the spleen and thymus indices and significantly increase the serum concentrations of IL-6, IgG and TNF-α. Moreover, PGS can also enhance the phagocytic activities of macrophage monocytes in immunosuppressed experimental mice. On the other hand, PGS can significantly increase the concentration of serum TNF-α, IL-2 and IL-6 and directly inhibit the growth of solid tumours in mice. Additionally, PGS can also significantly inhibit the growth of S180 cells in vitro, with an IC50 of 15.63 μg/ml⁻¹ ± 2.18.PGS can significantly improve the inhibited immune function of mice induced by cyclophosphamide (CTX) and can reduce the growth of solid tumours in vivo. In addition, PGS can also directly inhibit the S180 cell's growth in vitro, as well as considerably enhance the immune function of tumour-bearing mice.