对HCVNS5区部分基因进行了克隆表达，获得优质NS5区蛋白抗原。通过对不同人群抗-NS5检测表明，随访3年和6年的输血后丙肝（PT－HC）病例抗一NS5阳性率分别为70．5％和80．0％；随访8年和11年慢性丙肝（C－HC）病例分别为50．7％和82．4％。一般人群阳性率仅为1．7％，正常献血员中未检出阳性。结果表明研制的NS5抗原产生持久、特异性强。16例PT－HC病人抗一NS5和HCVRNA的动态随观察时间延长，阳性率呈升高趋势（P＞0．05）。说明执-NS5抗体和HCVRNA一样可反映病毒活动状态。对11份低值阳性参比血清检测表明．加入重组NSS抗原后，可进一步提高检出率。NSS区抗原的表达成功无疑为研制我国自己的第三代诊断试剂奠定了重要基础。

The purpose of this study was to eveluate the effective of recomination antigen of HCV NS5 region in detection of hepatitis C infection and in developing the third generation HCV diagnostic kit in China. All the serum samples were obtained in Hebei Province. Sera of PT - HC patients were collected in pre - transfusion and at 1, 3, 6, 12, 36 and 72 months after transfusion, Sera from patients with C - HC were collected in 8th year and 11th year after folowed - up. EIA method was developed using recombination antigen of HCV NS5 region. HCV RNA was determined with RT- PCR using 5' NTR primer. The anti - NS5 was detected in different populations. The positive rates of anti - NS5 in PT - HC patients, followed - up for 3 and 6 years, were 70. 5 % and 80. 1 %, respectively; C - HC patients followed - up for 8 and 11 years were 50. 8 %and 82. 4 %, respectively. No anti - NS5 in 291 blood donors was detected, and in the normal populations the positive rate was 1. 7%.