Detection of Viral RNA in Paraffinized Tissues by Nested RT-PCR.

Tissue fixed by formalin and embedded in paraffin is widely used in research and histological routine due to its good morphological preservation. Detection of viral RNA finds in these materials a barrier to be overcome. The fixation by formaldehyde, high temperatures used in the processing of the material, and the embedding in paraffin usually degrade the RNA. Such procedures make it difficult to extract RNA and isolate in adequate quality to be detected by the RT-PCR technique. Here we show an efficient protocol for the detection of yellow fever virus RNA in formalin-fixed paraffin-embedded (FFPE) tissue samples using the Nested RT-PCR technique.