102例HIV-1感染者病毒株反转录酶基因多态性及耐药性变异研究

目的:目前中国未接受或已接受反转录酶抑制剂(RTI)治疗的HIV感染者的HIV反转录酶基因类型的数据较少。本研究探讨了HIV-1反转录酶的基因多态性,及在RTI选择性压力下出现的已知和未知变异位点。方法:分析研究21例未接受治疗及81例接受RTI治疗的HIV感染者的RT基因。大部分感染者(>80%)应用司他夫定(d4T) 地达诺新(ddI) 奈韦拉平(NVP)或d4T 拉米夫定(3TC) 依菲韦仑(EFV)三联HAART治疗方案。结果:在未接受治疗的患者中,发现了4个高度多态性位点(122、200、207和211)。在接受RTI治疗的患者中,发现了2种耐药相关变异(RAMs):①接受ddI d4T NVP治疗方案的患者中发现,K65R(9.8%)、L74V(7.4%)、M184V(7.4%)、Q151M(5%)和胸腺嘧啶类似物变异(TAMs)(9.3%),包括T215Y(5.5%);②接受d4T 3TC EFV治疗方案的患者中发现,T215Y(23%)、M184V(20%)和TAMs(15.4%)。在所有病例中,非核苷反转录酶抑制剂(NNRTI)RAM的出现率很高(41.9%),而在142、221、224和228位点发现了4种可疑的新RAMs。结论:目前中国非核苷类反转录酶抑制剂(NNRTI)耐药相关变异十分普遍,本研究描述了RTI选择性变异的基因模式,提出了新的一些变异与RTI治疗的相关性。     

Emergence of the H208Y mutation in the reverse transcriptase (RT) of HIV-1 in association with nucleoside RT inhibitor therapy

OBJECTIVES: The aim of the study was to determine whether mutations at RT codon 208 are associated with nucleoside RT inhibitor (NRTI) exposure, NRTI resistance patterns and HIV-1 subtype. METHODS: Six thousand three hundred and fifty two genotypic resistance tests linked to a clinical database were analysed. RESULTS: The prevalence of mutations at codon 208 was 6/2347 (0.3%) in treatment-naive and 165/4005 (4.1%) in treatment-experienced persons. H208Y was the most common mutation in both groups (0.2% and 3.8%, respectively) and occurred in 4.5% of treatment-experienced persons with Subtype B, 1.7% of those with Subtype C and 0.7% of those with other non-B subtypes (P=0.001). The association with subtypes was independent of treatment experience. H208Y showed a strong association with NRTI experience, which persisted after adjusting for subtype [odds ratio (OR) 19.34; 95% confidence interval (CI) 7.87-47.54; P=0.0001]. The prevalence of H208Y was highest in genotypes harbouring M184V and the thymidine analogue mutations (TAMs) M41L, D67N, L210W and T215Y. The median number of TAMs was 4 and 0 in genotypes with and without H208Y, respectively (P=0.0001). The prevalence of H208Y declined over time, being highest in 1998 (9.9%) and lowest in 2003 (0.9%) (P=0.0001). CONCLUSIONS: There is a strong association between H208Y and NRTI experience, particularly in persons with Subtype B harbouring multiple NRTI resistance mutations. These findings indicate an accessory role for H208Y in NRTI resistance.     

乙型肝炎病毒逆转录酶基因突变的临床意义

目的 分析服用核苷酸类似物的乙肝患者逆转录酶(RT)基因突变模式及其与生化指标的相关性,探讨该基因突变的临床意义。方法 采用半巢式PCR对634例来自武汉地区的乙肝病毒感染者血浆HBV进行扩增后,Sanger测序法进行基因序列分析; 将RT基因突变组与野生组和各表型突变组中患者的谷氨酸氨基转移酶(ALT)、乙肝病毒e抗原(HBeAg)和HBV DNA阳性率作比较。结果 在测序成功的622例患者中,144例(23.15%)发生RT基因突变。他们在11个位点(rtM204,rtL180,rtA181,rtN236,rtV173,rtL80,rtM250,rtS202,rtV207,rtV214和rtV84)出现碱基突变。在突变组中,患者的ALT,HBeAg和HBV DNA阳性率显著高于非突变组(P<0.05)。表型分析显示:拉米夫定(LAM)耐药最常检测到,占52.78%,其次为阿德福伟(ADV)耐药占27.78%和恩替卡韦(ETV)耐药占6.94%,多重耐药LAM+ADV于18例患者中检出12.5%。多重耐药组患者ALT,HBeAg和HBV DNA阳性率高于其他耐药组(P<0.05); ADV耐药组患者ALT,HBeAg和HBV DNA阳性率高于LAM,ETV耐药组。结论 HBV RT区域的突变形式与血清学指标ALT,HBeAg和HBV DNA阳性状态有显著关联,该基因的突变形式可用作患者临床表现的指示指标。