地高辛素标记弓形虫DNA探针的制备及在产前诊断的应用

本文建立了地高辛素标记的弓形虫ＤＮＡ探针并在２３例产前咨询孕妇中作产前诊断。通过聚合酶链反应扩增弓形虫ＲＨ株ＴＧＲ４核酸片段，扩增产物７７８ｂｐ片段经寡核苷酸层析柱纯化后，用地高辛素标记作为探针，与待检材料斑点杂交。结果显示该探针与待杂交的弓形虫ＲＨ、ＺＳ１、ＺＳ２、ＳＨ１株ＤＮＡ杂交；而与恶性疟原虫、卡氏肺孢子虫、杜氏利什曼原虫、大肠杆菌、巨细胞病毒ＤＮＡ无杂交。并能在待杂交液中检测出相当于１ｐｇ水平ＤＮＡ，表明该探针具有高度的特异性及敏感性。检测２３例孕期１０—１４周孕妇中，阳性３例，其中一孕妇外周血、绒毛组织及羊水均呈阳性。另一例的外周血及绒毛组织呈阳性。该探针稳定、敏感、操作简单，具有推广意义。

Preparation of Digoxigenin-labeled DNA Probe and its Application to Detection of Toxoplasma gondii in Pregnant Women

Establishment of a Digoxigenin-labeled Toxoplasma DNA Probe through the TGR4 fragment of T.gondii RH strain is reported in this paper.The probe could hybridize to RH.ZS1 ZS2 and SH1 strain,but did not hybridized to the DNA from control including plasmodium falciparum,Pueumocystis carinii.leishmania donovani,Escherichia coli and Cytomegalovirus. As few as 1 pg purified DNA from T.gondii could be detected by the probe,indicating its specificity and sensitivity.The application of this probe to the diagnosis of toxoplasmosis in pregnant women is also reported in this paper.