Department of Rheumatology, Infectious Diseases and Laboratory Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan; Department of Medical Life Science, Faculty of Medical Bioscience, Kyushu University of Health and Welfare, Yoshino-cho 1714-1, Nobeoka, Miyazaki, 882-8508, Japan.
Department of Rheumatology, Infectious Diseases and Laboratory Medicine, Faculty of Medicine, University of Miyazaki, Miyazaki 889-1692, Japan; Miyazaki Prefectural Institute for Public Health and Environment, Nishi 2-3-2 Gakuenkibanadai, Miyazaki 889-2155, Japan.
J Virol Methods. 2020 Nov;285:113942. doi: 10.1016/j.jviromet.2020.113942. Epub 2020 Aug 8.
Severe fever with thrombocytopenia syndrome (SFTS) is a life-threatening febrile illness that is caused by the SFTS virus (SFTSV). The diagnosis of SFTS is usually performed by detecting viral RNA. However, it has been reported that viral RNA is no longer detectable at 6-12 days after the onset of disease. In the current study, we have constructed a plasmid to express the recombinant nuclear protein (NP) based on the Japanese strain of SFTSV (J1). We developed a double-antigen enzyme-linked immunosorbent assay (ELISA) and immunochromatography (IC) assay using recombinant NP to detect antibody against SFTSV-NP. When we tested time-sequential samples from four patients with SFTS, antibody to SFTSV-NP were detectable not only during the recovery phase (days 10-622) but also during the acute phase (days 4-7) of the disease using both of a double-antigen ELISA and IC assay. SFTSV-RNA was detected until 8-11 days after onset, thus suggesting the coexistence of the virus and antibody during the acute phase of SFTS. These data suggest that assays for detecting antibody against SFTS-NP described in the current study may be applicable not only for the epidemiological studies but also for the diagnosis of SFTS.
严重发热伴血小板减少综合征（SFTS）是一种危及生命的发热疾病，由 SFTS 病毒（SFTSV）引起。SFTS 的诊断通常通过检测病毒 RNA 来进行。然而，据报道，在疾病发病后 6-12 天，病毒 RNA 不再可检测到。在本研究中，我们构建了一种基于日本株 SFTSV（J1）的表达重组核蛋白（NP）的质粒。我们使用重组 NP 开发了双抗原酶联免疫吸附试验（ELISA）和免疫层析（IC）检测方法，用于检测针对 SFTSV-NP 的抗体。当我们测试 4 例 SFTS 患者的时间序列样本时，使用双抗原 ELISA 和 IC 检测方法，不仅在疾病恢复期（第 10-622 天），而且在疾病急性期（第 4-7 天）都可以检测到针对 SFTSV-NP 的抗体。SFTSV-RNA 一直检测到发病后 8-11 天，这表明在 SFTS 的急性期，病毒和抗体同时存在。这些数据表明，本研究中描述的针对 SFTS-NP 抗体的检测方法不仅可用于流行病学研究，也可用于 SFTS 的诊断。
