Rauw Fabienne, Gardin Yannick, Palya Vilmos, Anbari Sofia, Gonze Martine, Lemaire Sophie, van den Berg Thierry, Lambrecht Bénédicte
Avian Virology and Immunology Unit, Veterinary and Agrochemical Research Centre (VAR), Brussels, Belgium.
Vet Immunol Immunopathol. 2010 Apr 15;134(3-4):249-58. doi: 10.1016/j.vetimm.2009.10.028. Epub 2009 Nov 2.
The development of safe, novel strong adjuvants is necessary to maximize the efficacy of and the immune response induced by new and/or available vaccines administered through the mucosal route to chickens. Chitosan is a non-toxic, biocompatible, biodegradable and natural polysaccharide derived from the exoskeleton of crustaceans and insects. It has been demonstrated to be an effective absorption enhancer to improve mucosal delivery of peptide and protein drugs in human and mice. In poultry, mucosal administration of live vaccine has been already explored with success. However, the effects of the use of the chitosan as adjuvant for mucosal vaccination in birds have not been investigated yet. To this aim, we explored its potential as adjuvant given by oculo-nasal route to one-day-old chickens with live Newcastle disease (ND) vaccine. The immune response has been evaluated during three independent vaccination experiments on specific pathogen free (SPF) chickens. It was shown that chitosan enhanced the antigen-specific cell-mediated immune response in the spleen. New protocols were developed to measure the chicken IFNgamma production after ex vivo antigen-stimulation of peripheral blood and duodenal lamina propria lymphocytes. It was then observed than the peripheral cellular immune response was earlier and stronger, while the local cellular immune response in digestive tract as shorter when chitosan was used as adjuvant. On the other hand, the chitosan had no effect on the systemic, lachrymal and digestive antibody-mediated immunity. This study indicates thus that the chitosan is a cell-promising adjuvant for the mucosal delivery of live vaccine in poultry, by enhancing the Th1 pathway of immunity. However, further investigations are required to explore its mechanism of action and to evaluate the inferred protection.
开发安全、新型的强效佐剂对于最大限度提高经黏膜途径给鸡接种的新型和/或现有疫苗的效力及诱导的免疫反应而言是必要的。壳聚糖是一种无毒、生物相容、可生物降解的天然多糖，源自甲壳类动物和昆虫的外骨骼。它已被证明是一种有效的吸收增强剂，可改善肽和蛋白质药物在人和小鼠体内的黏膜递送。在家禽中，已成功探索了活疫苗的黏膜给药。然而，壳聚糖作为禽类黏膜疫苗佐剂的使用效果尚未得到研究。为此，我们探索了其作为佐剂经眼鼻途径给予一日龄雏鸡新城疫（ND）活疫苗的潜力。在针对无特定病原体（SPF）鸡进行的三项独立疫苗接种实验中评估了免疫反应。结果表明，壳聚糖增强了脾脏中抗原特异性细胞介导的免疫反应。开发了新的方案来测量外周血和十二指肠固有层淋巴细胞经体外抗原刺激后鸡γ干扰素的产生。然后观察到，当使用壳聚糖作为佐剂时，外周细胞免疫反应更早且更强，而消化道中的局部细胞免疫反应持续时间更短。另一方面，壳聚糖对全身、泪腺和消化道抗体介导的免疫没有影响。因此，本研究表明，壳聚糖通过增强免疫的Th1途径，是一种在家禽中用于活疫苗黏膜递送的有前景的佐剂。然而，需要进一步研究来探索其作用机制并评估推测的保护作用。
