Gomes-Keller M A, Tandon R, Gönczi E, Meli M L, Hofmann-Lehmann R, Lutz H
Clinical Laboratory, Vetsuisse Faculty, University of Zurich, Winterthurerstrasse 260, 8057, Zurich, Switzerland.
Vet Microbiol. 2006 Jan 10;112(1):11-21. doi: 10.1016/j.vetmic.2005.10.027. Epub 2005 Nov 21.
The purpose of this investigation was to characterize the shedding pattern of feline leukemia virus (FeLV) RNA in saliva, and to correlate it with the proviral load in whole blood, viral load in plasma, levels of p27 in saliva and plasma, the isolation of infectious FeLV from saliva, and the titers of FeLV-specific antibodies of the IgG and IgA isotypes. We evaluated 24 experimentally FeLV-infected cats for these parameters using real-time RT-PCR and PCR, cell culture assay and sandwich ELISA. We observed that shedding of viral RNA in saliva was a consistent feature in viremic cats. Latently FeLV-infected cats, displaying a very low proviral load, did not shed infectious virus in saliva, but occasionally shed viral RNA. Consequently, salivary shedding of FeLV RNA may not necessarily indicate a transmission potential for susceptible cats. This study also confirmed previous results from our laboratory, showing that a negative result for p27 in plasma, or for viral RNA in plasma or saliva does not exclude FeLV infection, considering that blood cells from those cats contained provirus. We also showed that FeLV RNA and DNA were stable for more than 64 days in saliva samples stored at room temperature. We conclude that the detection of FeLV RNA in saliva may be a useful indicator of viremia, and that the detection of salivary viral RNA by RT-PCR could become a reliable tool for the diagnosis of FeLV infection, which is facilitated by the low invasive method of collection of the samples.
本研究的目的是确定猫白血病病毒（FeLV）RNA在唾液中的排出模式，并将其与全血中的前病毒载量、血浆中的病毒载量、唾液和血浆中p27的水平、从唾液中分离出传染性FeLV以及IgG和IgA同种型的FeLV特异性抗体滴度相关联。我们使用实时RT-PCR和PCR、细胞培养测定法和夹心ELISA对24只实验性感染FeLV的猫的这些参数进行了评估。我们观察到，病毒血症猫唾液中病毒RNA的排出是一个一致的特征。潜伏感染FeLV的猫，前病毒载量非常低，唾液中不排出传染性病毒，但偶尔会排出病毒RNA。因此，FeLV RNA的唾液排出不一定表明对易感猫具有传播潜力。本研究还证实了我们实验室先前的结果，表明血浆中p27、血浆或唾液中病毒RNA检测呈阴性并不能排除FeLV感染，因为这些猫的血细胞中含有前病毒。我们还表明，在室温下储存的唾液样本中，FeLV RNA和DNA在64天以上保持稳定。我们得出结论，唾液中FeLV RNA的检测可能是病毒血症的一个有用指标，并且通过RT-PCR检测唾液病毒RNA可能成为诊断FeLV感染的可靠工具，样本采集的低侵入性方法有助于这一诊断。
