本文旨在对发热伴血小板减少综合征(severe fever with thrombocytopenia syndrome，SFTS)患者中和抗体进行定性和效价评估，建立中和抗体酶联免疫吸附试验(enzyme-linked immunosorbent assay，ELISA)。用96孔微量培养板培养非洲绿猴肾细胞(Vero-E6)并接种发热伴血小板减少综合征病毒(severe fever with thrombocytopenia syndrome virus，SFTSV)，以抗核衣壳蛋白(nucleocapsid protein，NP)单克隆抗体为一抗，使用间接ELISA检测SFTSV NP，根据光密度(optical density，OD)判断阳性孔数，采用Reed-Muench方法计算病毒半数组织培养感染剂量(50% tissue culture infective dose，TCID₅₀)，以反映SFTSV在Vero-E6细胞中的复制水平。ELISA检测中和抗体作用后的病毒残余量，可间接反映中和抗体的作用效果并进行定量。应用以上建立的微量中和-ELISA对10例SFTS患者的双份血清进行中和抗体效价测定，8例患者恢复期血清效价较急性期增高4倍以上，7份患者恢复期血清效价达1∶1 280，急性期血清效价最高为1∶640。结果提示，本研究建立的ELISA操作简便，结果判定客观，所需时间短，可用于临床血清抗体诊断，也可用于血清流行病学调查和疫苗效果临床评价等。

An enzyme-linked immunosorbent assay (ELISA) method was developed for the detection of neutralizing antibodies against severe fever with thrombocytopenia syndrome virus (SFTSV). Vero-E6 cells in a 96-well micro-plates were challenged with SFTSV first, and then subjected to the treatment with an anti-nucleocapsid protein (SFTSV-NP) monoclonal antibody at different concentrations. The 50% tissue culture infective dose (TCID₅₀) was calculated with Reed-Muench method. 10 double serum samples collected at two different stages of infection were subjected to the assay. 8 specimens demonstrated higher (>4 times) antibody levels in the recovery phase than that in the acute phase. In conclusion, the established ELISA method is specific, operation friendly and with an application potential for clinical research.