Cardenas-Garcia Stivalis, Dunwoody Robert P, Marcano Valerie, Diel Diego G, Williams Robert J, Gogal Robert M, Brown Corrie C, Miller Patti J, Afonso Claudio L
Southeast Poultry Research Laboratory, Agricultural Research Service, United States Department of Agriculture, Athens, Georgia, United States of America.
Department of Veterinary Pathology, College of Veterinary Medicine, The University of Georgia, Athens, Georgia, United States of America.
PLoS One. 2016 Jul 13;11(7):e0159153. doi: 10.1371/journal.pone.0159153. eCollection 2016.
More effective vaccines are needed to control avian diseases. The use of chicken interferon gamma (chIFNγ) during vaccination is a potentially important but controversial approach that may improve the immune response to antigens. In the present study, three different systems to co-deliver chIFNγ with Newcastle disease virus (NDV) antigens were evaluated for their ability to enhance the avian immune response and their protective capacity upon challenge with virulent NDV. These systems consisted of: 1) a DNA vaccine expressing the Newcastle disease virus fusion (F) protein co-administered with a vector expressing the chIFNγ gene for in ovo and booster vaccination, 2) a recombinant Newcastle disease virus expressing the chIFNγ gene (rZJ1L/IFNγ) used as a live vaccine delivered in ovo and into juvenile chickens, and 3) the same rZJ1L/IFNγ virus used as an inactivated vaccine for juvenile chickens. Co-administration of chIFNγ with a DNA vaccine expressing the F protein resulted in higher levels of morbidity and mortality, and higher amounts of virulent virus shed after challenge when compared to the group that did not receive chIFNγ. The live vaccine system co-delivering chIFNγ did not enhanced post-vaccination antibody response, nor improved survival after hatch, when administered in ovo, and did not affect survival after challenge when administered to juvenile chickens. The low dose of the inactivated vaccine co-delivering active chIFNγ induced lower antibody titers than the groups that did not receive the cytokine. The high dose of this vaccine did not increase the antibody titers or antigen-specific memory response, and did not reduce the amount of challenge virus shed or mortality after challenge. In summary, regardless of the delivery system, chIFNγ, when administered simultaneously with the vaccine antigen, did not enhance Newcastle disease virus vaccine immunogenicity.
需要更有效的疫苗来控制禽类疾病。在疫苗接种过程中使用鸡γ干扰素（chIFNγ）是一种潜在的重要但有争议的方法，可能会改善对抗原的免疫反应。在本研究中，评估了三种将chIFNγ与新城疫病毒（NDV）抗原共同递送的不同系统，以研究它们增强禽类免疫反应的能力以及在受到强毒NDV攻击时的保护能力。这些系统包括：1）一种表达新城疫病毒融合（F）蛋白的DNA疫苗，与一种表达chIFNγ基因的载体共同用于胚内接种和加强免疫；2）一种表达chIFNγ基因的重组新城疫病毒（rZJ1L/IFNγ），用作胚内接种和幼鸡接种的活疫苗；3）同一rZJ1L/IFNγ病毒用作幼鸡的灭活疫苗。与未接受chIFNγ的组相比，将chIFNγ与表达F蛋白的DNA疫苗共同给药导致更高的发病率和死亡率，以及在攻击后排出更多的强毒病毒。共同递送chIFNγ的活疫苗系统在胚内接种时，并未增强接种后的抗体反应，也未提高孵化后的存活率，在幼鸡接种时也未影响攻击后的存活率。低剂量的共同递送活性chIFNγ的灭活疫苗诱导的抗体滴度低于未接受细胞因子的组。高剂量的这种疫苗并未增加抗体滴度或抗原特异性记忆反应，也未减少攻击后排出的攻击病毒量或死亡率。总之，无论递送系统如何，chIFNγ与疫苗抗原同时给药时，并未增强新城疫病毒疫苗的免疫原性。
