RNA extraction and RT-PCR procedures adapted for the detection of enterovirus sequences from frozen and paraffin-embedded formalin-fixed spinal cord samples.

Methods for detecting enterovirus RNA in both paraffin-embedded, formalin-fixed and frozen spinal cord sections from amyotrophic lateral sclerosis (ALS) patients were established. A proteinase K digestion following the deparaffinization procedure was required for the fixed spinal cord sections, whereas only one step of crushing in phosphate buffered saline was necessary for the frozen samples prior to the extraction of the RNA. With an optimized reverse transcription and PCR procedure, enterovirus RNA could be detected from frozen and fixed archival spinal cord samples.