HBV感染者血清HBsAg、抗-HBs共存与S基因变异

目的 :探讨无锡地区HBV感染者HBsAg与抗 -HBs的共存模式与S基因变异、病毒复制及免疫治疗的关系。方法 :采用Abbott及ELISA测定HBVM ;套式PCR检测HBVDNA并作序列分析 ;荧光定量法检测HBVDNA含量。结果 :30例adr亚型 ,1例adw亚型 ;2 1份血清出现S区多部位变异 ,造成HBsAg肽 36、47、6 3、77、89、90、115、12 6、12 9、139、15 4位氨基酸替换 ;该变异不影响病毒复制 ;变异组免疫药物的使用率 6 6 .6 % ;抗 -HBs阳性血清加入HBsAg阳性血清后 ,再测抗 -HBs阴转。结论 :S基因变异导致HBsAg抗原性的改变和与抗 -HBs结合力的降低 ,以及检测灵敏度的提高、亚型的转变都是造成HBsAg与抗 -HBs共存的原因 ;免疫治疗等造成的免疫压力是产生免疫逃逸变异的原因之一

RELATIONSHIP BETWEEN S GENE MUTATION AND CON CURRENT HEPATITIS B SURFACE ANTIGEN AND HEPATITIS B SURFACE ANTIBODY

Objective:To determine the relationship between concurrent HBsAg and anti-HBs in serum and S gene mutation, viral replication, immunotherapeutic agent. Methods:Serological markers of hepatitis B virus were detected by Enzyme-linked immunosorbent assay or Microparticle Enzyme immunoassay (Abbott). Quantitative analysis of HBV DNA was performed by polymerase chain reaction and S gene fragments were directly sequenced.Results:Thirty patients were subtype adr and only one patients was adw. Samples from 21 patients were identified several points mutation in S gene resulting in amino acid substitutions at site at 36,47,63,77,89,90,115,126,129,139,154. It didn't affect viral replication. 66.6% of those patients had the history of immunotherapy. All samples positive for anti-HBs became negative after reacting with HBsAg-positive sera. Conclusions:The concurrent HBsAg and anti-HBs in our patients may result from interchanging of subtype, changes of S-antigenicity due to mutation, reduced cross-reactivity with polyclonal anti-HBs and improving sensitivity of testing methods. Immunotherapeutic agents can cause escape mutation.