As a traditional Chinese multiherbal formula, Yu-Ping-Feng (YPF) is frequently used to treat cold, flu and inflammation-associated diseases. We aimed to evaluate the immunostimulatory effects of polysaccharide isolated from YPF (YPF-PS) in vitro and in vivo. In in vitro experiment, macrophage cell proliferation, phagocytosis rate, cytokine and costimulatory molecule release, T lymphocyte proliferation, cell cycle distribution, CD4+ and CD8+ T cell percentages were determined. To investigate the in vivo effects of YPF-PS treatment, different doses YPF-PS were administered to chicken vaccinated against Newcastle disease. The immune organ index, lymphocyte proliferation, antibody titer, cell cycle distribution, and the cell percentage of CD4+ and CD8+ were assessed. In vitro results indicated that YPF-PS at 15.62 μg mL−1 could increase the LPS-induced macrophage cell proliferation and phagocytosis rate significantly. The levels of cytokine (nitric oxide, tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6, and interferon beta) and costimulatory molecules (CD80 and CD86) were also considerably enhanced. Moreover, YPF-PS could significantly enhance T lymphocyte proliferation individually or synergistically with phytohemagglutinin. It promoted lymphocyte entry into S and G2/M phases and increased the percentages of CD4+ and CD8+ T cells effectively. In addition, in vivo experiments showed that YPF-PS could enhance serum HI antibody titer. The results about T lymphocyte proliferation, cell cycle distribution, CD4+ and CD8+ cell percentages in chickens were also confirmed. YPF-PS has efficacious immunomodulatory properties and could be used as a new potential immune stimulator for food and medical purposes.

•RAPS could increase cell proliferation and phagocytosis rate significantly.•RAPS could elevate the levels of cytokine: NO, TNF-α, and IFN-β obviously.•RSPS had stronger expression level on CD80 and CD86 than PAPS and RAMPS.•Compared to PAPS and RAMPS, PSPS had different structure characterization.•RAPS would be anticipated as a component of new-type immunostimulant.In this study, we evaluated structure characterization and immunomodulatory activity of polysaccharides from Astragalus aboriginum Richardson (RAPS), Atractylodes macrocephala Koidz (RAMPS) and Rumia seseloides Hoffm (RSPS) in vitro on chicken macrophage. We found that molecular weight of RAPS and RAMPS was 122.4 and 109.4 kDa higher than 64.71 kDa of RSPS. Glucose occupied 83.95% and 66.39% in RAPS and RAMPS, respectively. RSPS mainly contained glucose and galacturonic acid, which accounted for 32.35% and 29.25%, respectively. The NMR results displayed that RAPS and RAMPS contained β- glucose, β-galactose, and β-galacturonic acid. The backbone was 1 → 6 linked glucose. RSPS showed at least six monosaccharide response signals. In vitro experiment, the results showed that RAPS at dosage of 15.62 μg mL−1 exhibited significant immunological on chicken macrophage compared to RAMPS and RSPS. Interestingly, costimulatory molecules levels in RSPS group were higher than that of RAPS, which may associated with the special structure of RSPS.

•RAMPStp and RAMPS60c enhanced T lymphocyte proliferation.•RAMPS60c and RAMPStp could promote lymphocytes enter into S and G2/M phases and improve the percentages of CD4+ and CD8+ T cells.•RAMPStp presented the best efficacy.•RAMPStp would be expected as a component of new-type immunopotentiator.This study evaluated the immune-enhancing activity of polysaccharides from the rhizoma of Atractylodis macrocephalae Koidz (RAMPS) in vitro. Lymphocyte proliferation, cell cycle distribution, and percentages of CD4+ and CD8+ cells were determined. Different concentrations of RAMPS were added to peripheral blood T lymphocytes. Results showed that RAMPStp and RAMPS60c could significantly enhance T lymphocyte proliferation individually or synergistically with phytohemagglutinin at most concentrations. The active sites of RAMPStp and RAMPS60c were then selected. Lymphocyte cell cycle distribution and percentages of CD4+ and CD8+ cells were determined by flow cytometry. At most time points, RAMPS60c and RAMPStp could promote lymphocytes enter into S and G2/M phases. RAMPStp and RAMPS60c effectively improved the percentages of CD4+ and CD8+ T cells. RAMPStp produced optimal effects. Therefore, RAMPStp could be used as a component of novel immunopotentiators.

•NDV two major genotypes had high sequence homology.•Polymorphism of Class II NDV genes evolve by positive selection.•The dN/dS for F gene were higher than those for HN gene.In our research, the molecular evolutions of NDV F and HN genes were analyzed. The phylogenetic analyses of NDV sequences indicated that NDV could be divided into two genotypes: Class I (lentogenic strains) and Class II (velogenic or mesogenic strains). Each genotype possesses high gene homology. Furthermore, the selected pressure analysis showed that the dN/dS of velogenic, mesogenic NDV strains F gene was significantly high and the ω(dN/dS) is 1.1725 > 1. These results imply that mutations in velogenic, mesogenic NDV F gene are favored by positive natural selection and it has acted to diversify NDV virulence at the nucleotide and amino acid level. We estimated that the subsequent rapid adaptation of the Newcastle disease virus to chickens were likely dependent on a high rate of mutation and the positive selection of mutations in the major F gene.

•NDV two major genotypes had high sequence homology.•Polymorphism of Class II NDV genes evolve by positive selection.•The dN/dS for F gene were higher than those for HN gene.In our research, the molecular evolutions of NDV F and HN genes were analyzed. The phylogenetic analyses of NDV sequences indicated that NDV could be divided into two genotypes: Class I (lentogenic strains) and Class II (velogenic or mesogenic strains). Each genotype possesses high gene homology. Furthermore, the selected pressure analysis showed that the dN/dS of velogenic, mesogenic NDV strains F gene was significantly high and the ω(dN/dS) is 1.1725 > 1. These results imply that mutations in velogenic, mesogenic NDV F gene are favored by positive natural selection and it has acted to diversify NDV virulence at the nucleotide and amino acid level. We estimated that the subsequent rapid adaptation of the Newcastle disease virus to chickens were likely dependent on a high rate of mutation and the positive selection of mutations in the major F gene.