Cao Hai-Peng, Wang Hong-Ning, Yang Xin, Zhang An-Yun, Li Xin, Ding Meng-Die, Liu Si-Tong, Zhang Zhi-Kun, Yang Fan
Animal Disease Prevention and Food Safety Key Laboratory of Sichuan Province, 985 Project Science Innovative Platform for Resource and Environment Protection of Southwestern China, College of Life Sciences, Sichuan University, Chengdu 610064, China.
Biosci Biotechnol Biochem. 2013;77(7):1499-504. doi: 10.1271/bbb.130157. Epub 2013 Jul 7.
Mucosal immunity is critical in preventing infectious bronchitis virus (IBV) infection. To deliver viral antigens to the mucosal immune system of chickens safely and effectively, we constructed a Lactococcus lactis strain carrying IBV multi-epitope gene EpiC fused with the gene of the cell-wall anchoring domain of Staphylococcus aureus protein A. SDS-PAGE and Western blot results indicated that the fused peptide was located partially on the cell surface. Oral and nasal inoculation with the recombinant L. lactis of chickens elicited significantly high humoral and mucosal immune responses, especially in the nasally immunized group. Eighty percent chickens of the nasally immunized group with recombinant L. lactis did not show any clinical signs after a lethal dose challenge with IBV SAIBk strain, while all the non-recombinant L. lactis immunized chickens exhibited obvious and typical symptoms. These results indicate that needle-free recombinant lactococci anchoring the IBV antigen makes a promising vaccine candidate against the spread of IB.
黏膜免疫在预防传染性支气管炎病毒（IBV）感染中至关重要。为了将病毒抗原安全有效地递送至鸡的黏膜免疫系统，我们构建了一株携带IBV多表位基因EpiC并与金黄色葡萄球菌蛋白A细胞壁锚定结构域基因融合的乳酸乳球菌菌株。SDS-PAGE和Western印迹结果表明，融合肽部分位于细胞表面。用重组乳酸乳球菌对鸡进行口服和鼻内接种可引发显著的高水平体液免疫和黏膜免疫反应，尤其是在鼻内免疫组中。用重组乳酸乳球菌鼻内免疫的鸡群中，80%的鸡在用IBV SAIBk株致死剂量攻毒后未表现出任何临床症状，而所有未用重组乳酸乳球菌免疫的鸡均表现出明显的典型症状。这些结果表明，锚定IBV抗原的无针重组乳球菌有望成为预防IB传播的候选疫苗。
