Effects of polysaccharide on chicks co-infected with Bordetella avium and Avian leukosis virus.

Chicks' co-infection with immunosuppressive virus and bacteria seriously threaten the development of the poultry industry. In this study, a model was established in which chicks were injected with either subgroup B ALV (ALV-B)+Bordetella avium (B. avium), or ALV-B+B. avium+Taishan Pinus massoniana pollen polysaccharide (TPPPS), or B. avium only, or B. avium+TPPPS. The data showed that the group injected with ALV-B and B. avium exhibited significant inhibition of the immune function and therefore increased pathogenicity compared with the group injected with B. avium-only. Application of TPPPS effectively alleviated immunosuppression, and body weights increased sharply in the TPPPS groups compared with non-TPPPS groups. To some extent, TPPPS may reduce the proliferation of ALV-B. These results suggest that Pinus pollen polysaccharides are beneficial treating co-infections with immunosuppressive virus and bacteria and therefore have potential for development into safe and effective immunoregulator.

Immunoregulatory effects of Taishan Pinus massoniana pollen polysaccharide on chicks co-infected with avian leukosis virus and Bordetella avium early in ovo.

In recent years, co-infection of chicken embryos with immunosuppressive viruses and bacteria occurs with an annually increasing frequency. Consequently, studies on new and safe immunoregulators, especially plant polysaccharides, have become a popular topic in the poultry industry. In the present study, we selected 300 specific pathogen free embryonated eggs, which were injected with subgroup B avian leukosis virus (ALV-B) and Bordetella avium (B. avium) to establish an artificial co-infection model. The chicks that hatched from these co-infected embryonated eggs were treated with Taishan Pinus massoniana pollen polysaccharide (TPPPS). Results indicated that relevant indices in the co-infection group were significantly lower than that in B. avium-only group. Furthermore, pathogenicity of B. avium was exacerbated, with the chicks exhibiting decreased body weights. The TPPPS groups exhibited gradual improvements in immune function and developmental status. Therefore, in terms of improving immunologic function and production performance, TPPPS could be used as immunoregulator for immune responses.

Taishan Pinus massoniana pollen polysaccharides promote immune responses of recombinant Bordetella avium ompA in BALB/c mice.

To study the effects of Taishan Pinus massoniana pollen polysaccharides (TPPPS) on Bordetella avium outer membrane protein A (ompA) recombinant protein vaccine, ompA was expressed, confirmed by Western blotting and mixed with TPPPS. Female BALB/c mice were randomly divided into six groups (I-VI). Groups I, II, and III were treated with TPPPS-ompA at doses of 200, 400, and 800 mg/ml, respectively. Groups IV, V, and VI were treated with Freund's adjuvant-ompA, pure ompA, and physiological saline, respectively. On days 3, 7, 14, 21, 28, 35, 42, and 49 after the first vaccination, antibody titers, interleukin-2 (IL-2) levels, peripheral blood CD4+ and CD8+ levels, and T lymphocyte proliferation rates in peripheral blood, as well as secreting-type immunoglobulin A (SIgA) levels in the duodenum, were measured. The antibody titers against ompA, IL-2, T lymphocyte proliferation rate, CD4+, and CD8+ in Group II were significantly (P<0.05) higher than those in other groups. However, little difference in SIgA content was observed among Groups I, II, and IV. These results indicated that TPPPS strengthened humoral and cellular immune response against recombinant ompA vaccine and 400 mg/ml TPPPS showed significance (P<0.05) compared with Freund's adjuvant. Therefore, TPPPS can be developed into an adjuvant for recombinant protein vaccines or plant-derived medicine for animal husbandry.