The adjuvanticity of Ganoderma lucidum polysaccharide for Newcastle disease vaccine.

The adjuvant activity of GLP was investigated in vitro and in vivo. In vitro experiment, the effects of GLP on chicken peripheral lymphocytes proliferation were compared by MTT assay. The results showed that GLP could significantly enhance lymphocytes proliferation singly or synergistically with ConA. The interferon-gamma (IFN-γ) mRNA levels of chicken peripheral lymphocytes stimulated by GLP synergistically with ConA were measured using fluorescent quantitative PCR. The results showed that GLP could promote interferon-γ mRNA levels in peripheral lymphocytes. In vivo experiment, 175 14-day-old chickens were randomly divided into 7 groups. The chickens except blank control (BC) group were vaccinated with Newcastle disease vaccine, repeated vaccination at 28 days old. At the same time of the first vaccination, the chickens in experimental groups were orally administrated with 5 different doses of GLP respectively, whereas vaccination control (VC) and BC groups were treated with physiological saline, once a day for three successive days. On Day 7, 14, 21 and 28 after the first vaccination, the peripheral lymphocytes proliferation and serum ND antibody titer were determined. The results showed that GLP could significantly promote lymphocyte proliferation and enhance serum antibody titer. The results indicated that GLP may be a novel immunomodulator.