Changes Of Immunological Function And Expression Of IL-2 MRNA And Il-2r MRNA In Peripheral Blood Of Probiotics-fed Chicks After IBD Vaccination

To reveal the influence of probiotics on IBD-vaccine and the cellular and humoral immunity in peripheral blood of chicks and to provide a scientific and experimental evidence for the development of probiotics, investigations about the dynamic changes of the proliferative function, the quantity of T and B lymphocytes and the expression of IL-2 mRNA and IL-2R mRNA in peripheral blood of chicks were carried out. One-day-old chicks fed with probiotics and then inoculated by IBD-vaccine and following challenged with virulent IBDV were used in this study, and also technology of cell culture, MTT, SPA and real-time fluorescence quantitative PCR were used. The results were as follows:1.After chicks were fed with probiotics, the peripheral blood T lymphocyte proliferation were significantly enhanced in probiotics-fed chicks from 4 to11 days(P<0.05 or P<0.01); B lymphocyte proliferation of probiotics I and probiotics II in peripheral blood of probiotics-fed chicks were greatly raised from 7 to 11 days and from 1 to 11 days respectively (P<0.05 or P<0.01). The number of T and B lymphocytes and the content of IgG, IgM, IgA in peripheral blood increase in different extent as compared with those of control chicks. These results indicated that the function of cellular and humoral immunity in peripheral blood of probiotics-fed chicks strengthened remarkably.2. After the inoculation of IBD-vaccine, the proliferative function of T and B lymphocytes and the quantity of T and B lymphocytes, the content of IgG, IgM, IgA in peripheral blood of probiotics-fed and IBD-vaccinated chicks differed remarkably from controls and were stronger or higher than that of IBD-vaccinated group. The results indicated that the application of probiotics combined with IBD-vaccine could promote the level of cellular and humoral immunity which indicated that the cellullar immunological response and humoral immunoresponse in probiotics-fed and IBD-vaccinated chicks were strengthened by probiotics.3. After the application of probiotics combined with IBD-vaccine, the expression of IL-2 mRNA and IL-2R mRNA in peripheral blood differed remarkably from controls and IBD-vaccinated group, which indicated that both probiotics and IBD-vaccine could stimulate the activation and proliferation of T lymphocyte and promote the expression of IL-2 mRNA and IL-2R mRNA and strengthen the immunological regulation of molecular immunity. The cellular immunological response and humoral immunoresponse in probiotics-fed and IBD-vaccinated chicks differed significantly, which indicated that the probiotics could promote the immunological regulation of cytokine IL-2 mRNA and IL-2R mRNA.4. After the challenge of virulent IBDV, the proliferative function of T and B lymphocytes, the quantity of T and B lymphocytes, the content of IgG, IgM, IgA and the expression of IL-2 mRNA and IL-2R mRNA in peripheral blood are all stronger or higher than that of controls. The application of probiotics combined with IBD-vaccine showed effectively. These indicated that the probiotics could not only strengthen the level of cellular and humoral immunity, but also strengthen the cellular immunological response and humoral immunoresponse against IBD-vaccine by secretion great of cytokine and specific antibodies.5. The data of probiotics II was higher than that of probiotics I. It showed that the probiotics II was better than probiotics I in the respect of immune enhance effect. Probably because probiotics II contained more bacillus than probiotics I led to this result.