摘要目的:探讨巢式PCR在献血者隐匿性乙型肝炎病毒感染(OBI)检测中的应用，提高输血前血液筛查OBI的检出率。方法:2021年7月至2022年8月在解放军济南血液中心的献血者，经血清学实验与核酸扩增实验共检出HBsAg－、NAT+的献血员37例，记录核酸扩增实验的 Ct值，使用荧光定量PCR对HBV DNA进行定量检测；设计常规PCR引物与巢式PCR引物，分别使用常规PCR与巢式PCR扩增HBV S基因与preS基因，并对扩增结果进行基因测序。 结果:37例HBsAg－、NAT+献血者中有33例核酸检测Ct值处于灰区范围，荧光定量PCR检测HBV DNA值与核酸检测Ct值呈负相关性；37例HBsAg－、NAT+献血者使用常规PCR无法扩增出条带，改用巢式PCR后，34例可检测到HBV病毒S基因，28例可检测到HBV病毒preS基因；扩增条带经基因测序显示均为HBV基因组序列。结论:HBsAg－、NAT+献血者血浆中HBV病毒载量极低；巢式PCR灵敏度高，可提高HBV病毒preS/S基因的检出率，对于OBI的输血前筛查及后续研究有一定应用价值。

abstractsObjective:To explore the application of nested PCR in the detection of occult hepatitis B virus infection (OBI) in blood donors, and improve the detection rate of OBI in blood screening before blood transfusion.Methods:From July 2021 to August 2022, 37 blood donors who donated blood in our center were found to have HBsAg- and nucleic acid testing (NAT)+ by serological tests and nucleic acid amplification tests. The CT value of nucleic acid amplification test was recorded, and the HBV DNA was quantitatively detected by fluorescent quantitative PCR; Conventional PCR primers and nested PCR primers were designed to amplify HBV S gene and pre-S gene using conventional PCR and nested PCR respectively, and gene sequencing was performed for the amplification result.Results:Among the 37 HBsAg- and NAT+ blood donors, 33 nucleic acid detection CT values were in the gray area, and the fluorescent quantitative PCR detection of HBV DNA value was negatively correlated with the nucleic acid detection CT value; 37 cases of HBsAg-, NAT+ blood donors could not be amplified by conventional PCR. After using nested PCR, 34 cases could detect the S gene of HBV virus, and 28 cases could detect the pre S gene of HBV virus; The amplified bands were all HBV genome bands by gene sequencing.Conclusions:The plasma HBV viral load of HBsAg- and NAT+ blood donors was very low; nested PCR has high sensitivity, which can improve the detection rate of HBV S gene and pre-S gene, and has certain application value for the pre transfusion screening and follow-up research of OBI.