Laboratory of Veterinary Infectious Disease, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
Laboratory of Veterinary Infectious Disease, School of Veterinary Medicine, Kitasato University, Towada, Aomori 034-8628, Japan.
Vaccine. 2014 Apr 1;32(16):1834-40. doi: 10.1016/j.vaccine.2014.01.074. Epub 2014 Feb 11.
Feline infectious peritonitis virus (FIP virus: FIPV) causes a fatal disease in wild and domestic cats. The development of an FIP-preventive vaccine requires an antigen that does not induce antibody-dependent enhancement, and T helper (Th)1 activity plays an important role in protect against FIPV infection. In the present study, we identified synthetic peptides including Th1 and a linear immunodominant antibody-binding epitope in the S1 domain and M protein of FIPV. We also identified peptides that strongly induce Th1 activity from those derived from the structural proteins (S, M, and N proteins) of FIPV based on this and previous studies (Satoh et al. [19]). No Th1 epitope-containing peptide was identified in the peptides derived from the S1 domain of type I FIPV. In contrast, 7 Th1 epitope-containing peptides were identified in the S1 domain of type II FIPV, and no linear immunodominant antibody-binding epitope was contained in any of these peptides. Eleven Th1 epitope-containing peptides common to each serotype were identified in the M protein-derived peptides, and 2 peptides (M-11 and M-12) contained the linear immunodominant antibody-binding epitope. Of the peptides derived from the S, M, and N proteins of FIPV, those that induced significantly stronger Th1 activity than that of the FIPV antigen were rescreened, and 4 peptides were identified. When 3 of these peptides (M-9, I-S2-15, and II-S1-24) were selected and administered with CpG-ODNs to SPF cats, M-9 and II-S1-24 induced Th1 activity. Our results may provide important information for the development of a peptide-based vaccine against FIPV infection.
猫传染性腹膜炎病毒（FIP 病毒：FIPV）可引起野生和家养猫致命疾病。开发 FIP 预防疫苗需要一种不会诱导抗体依赖性增强的抗原，而辅助性 T 细胞（Th）1 活性在抵抗 FIPV 感染中起着重要作用。在本研究中，我们鉴定了包含 FIPV 的 S1 结构域和 M 蛋白中的 Th1 和线性免疫显性抗体结合表位的合成肽。我们还根据这项研究和以前的研究（Satoh 等人，[19]），从 FIPV 的结构蛋白（S、M 和 N 蛋白）衍生的肽中鉴定出强烈诱导 Th1 活性的肽。在 I 型 FIPV 的 S1 结构域衍生的肽中未鉴定到含有 Th1 表位的肽。相比之下，在 II 型 FIPV 的 S1 结构域中鉴定到 7 个含有 Th1 表位的肽，并且这些肽中没有线性免疫显性抗体结合表位。在 M 蛋白衍生的肽中鉴定到 11 个与每个血清型共有的含有 Th1 表位的肽，并且 2 个肽（M-11 和 M-12）含有线性免疫显性抗体结合表位。在 FIPV 的 S、M 和 N 蛋白衍生的肽中，那些诱导的 Th1 活性明显强于 FIPV 抗原的肽被重新筛选，鉴定到 4 个肽。当选择其中 3 个肽（M-9、I-S2-15 和 II-S1-24）并与 CpG-ODN 一起施用于 SPF 猫时，M-9 和 II-S1-24 诱导了 Th1 活性。我们的结果可能为开发针对 FIPV 感染的基于肽的疫苗提供重要信息。
