黑龙江全沟硬蜱中检测出类似人粒细胞埃利希体的病原体DNA

DETECTION OF HGE-LIKE PATHOGEN IN IXODES PERSULCATUS COLLECTED FROM HEILONGJIANG

目的 寻找我国蜱中人粒细胞埃利希体感染存在的病原学证据。方法 应用从人粒细胞埃利希体 16SrRNA基因构建的特异引物进行半套式PCR ,检测蜱标本中埃利希体DNA。然后对PCR扩增产物进行克隆和序列测定 ,与已知序列进行同源性比较。结果 从黑龙江采集的全沟硬蜱 (Ixodespersulcatus)中扩增出特异DNA片段 ,计算最小阳性率为 0 8%。对 919bp的扩增产物进行序列分析 ,证实为埃利希体DNA ,与美国人粒细胞埃利希体分离株对应序列比较 ,相差 4个核苷酸。结论 这是首次证明我国有类似人粒细胞埃利希体的病原体存在。

Aim To search for the pathologic evidence of human granulocytc ehrlichia(HGE) infection in ticks.Method Specific primers derived from the 16S rRNA gene sequence were used to amplify ehrlichial DNA from ticks by hemi-nested polymerase chain reaction(PCR).The PCR products were cloned and sequenced.The sequence was compared with other ehrlichiae for homology.Results Specific DNA fragments were amplified from Ixodes persulcatus collected from Heilongjiang province.The minimum infection rate was 0.8%.The sequence of 919-bp PCR product was analyzed,and identified as part of ehrlichial 16S rRNA gene.It differed at four positions in comparison to American strains.Conclusion This is the first report of having HGE-like pathogen in China.These findings demonstrate that there may be natural foci of human granulocytic ehrlichiosis in northern forest area in China.