MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Weigang 1 Nanjing, Jiangsu 210095, P.R. China.
MOE Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Weigang 1 Nanjing, Jiangsu 210095, P.R. China
Biosci Rep. 2019 Mar 15;39(3). doi: 10.1042/BSR20182028. Print 2019 Mar 29.
Porcine epidemic diarrhea (PED) is a highly contagious disease in newborn piglets and causes substantial economic losses in the world. PED virus (PEDV) spreads by fecal-oral contact and can be prevented by oral immunization. Therefore, it is necessary to develop an effective oral vaccine against PEDV infection. Currently, as recombinant vaccine carrier has been used for antigen delivery and proved well in immune effect and safety. The present study evaluated the immunogenicity of recombinant -RC) in piglets via oral administration. After oral immunization in piglets, -RC significantly increased the local mucosal immune responses. Oral administration with -RC significantly improved the level of specific mucosal immunoglobulin A (IgA) antibodies against PEDV infection, through enlarging the area of Peyer's patches (PPs) and increasing the number of ileum IgA secreting (SIgA) cells. In the meantime, -RC remarkably increased the number of intraepithelial lymphocytes (IELs). We also observed that oral administration of -RC significantly increased CD3T lymphocytes' numbers and up-regulated the ratio of CD4/CD8 T cells. Furthermore, high titers of specific serum immunoglobulin G (IgG) revealed satisfactory systemic immune response against PEDV infection. In summary, our study demonstrated that oral administration of -RC could trigger a high level of local and systemic immune responses and would be a promising candidate vaccine against PEDV infection in piglets.
猪流行性腹泻（PED）是一种新生仔猪高度接触传染性疾病，在世界范围内造成了巨大的经济损失。PED 病毒（PEDV）通过粪-口途径传播，可以通过口服免疫进行预防。因此，有必要开发针对 PEDV 感染的有效口服疫苗。目前，作为重组疫苗载体已被用于抗原传递，并在免疫效果和安全性方面得到了很好的证明。本研究通过口服途径评估了重组猪圆环病毒 2 型（r- RC）在仔猪中的免疫原性。在仔猪口服免疫后，r- RC 显著增加了局部黏膜免疫应答。口服 r- RC 可显著提高针对 PEDV 感染的特异性黏膜免疫球蛋白 A（IgA）抗体水平，通过扩大派氏集合淋巴结（PPs）的面积和增加回肠 IgA 分泌细胞（SIgA）的数量来实现。同时，r- RC 显著增加了上皮内淋巴细胞（IEL）的数量。我们还观察到，口服 r- RC 可显著增加 CD3T 淋巴细胞的数量，并上调 CD4/CD8 T 细胞的比例。此外，高滴度的特异性血清免疫球蛋白 G（IgG）显示出针对 PEDV 感染的令人满意的系统免疫应答。综上所述，本研究表明，口服 r- RC 可以引发高水平的局部和系统免疫应答，是预防仔猪 PEDV 感染的有前途的候选疫苗。
