Effect of compound mucosal immune adjuvant on mucosal and systemic immune responses in chicken orally vaccinated with attenuated Newcastle-disease vaccine

In order to compare the adjuvant activity of compound mucosal immune adjuvant (cMIA), two novel compound adjuvants (cMIA I and cMIA II) were prepared and mixed with Newcastle-disease (ND) vaccine, respectively, to vaccinate 7-day-old chickens, taking the non-adjuvant vaccines and PBS as controls. Serum were sampled on weeks 1–7 and tissues on weeks 3, 5 and 7 after vaccination, respectively. The humoral and cellular immune responses were determined by means of hemagglutination inhibition test, enzyme linked immunosorbent assay, semi-quantitative RT-PCR, immunohistochemical examination and histological examination. The results showed that two compound adjuvants could promote CD3+ T lymphocytes, IgA secreting cells, intestinal intraepithelial lymphocytes (iIEL) and Mast cells formation and enhance serum and content antibody titer. The best adjuvant activity of cMIA II in promoting cellular immunity and cMIA I in enhancing humoral immunity occurred in whole immune period. Based on good synergistic effects of their components, two cMIAs would be expected as new-type mucosal immune adjuvants for mucosal immune.