Failure to detect enterovirus in the spinal cord of ALS patients using a sensitive RT-PCR method.
OBJECTIVE
To assess the association of enteroviruses (EV) with ALS by applying a sensitive seminested reverse transcription (RT) PCR protocol to the detection of enteroviral RNA in a blinded set of archived tissues from ALS and control cases.


METHODS
The specimen set consisted of 24 frozen spinal cord samples from ALS cases, 17 frozen spinal cord samples from negative control (non-ALS) cases, and 5 frozen spinal cord positive control samples. The positive controls were two human spinal cord samples spiked with poliovirus (PV) and three spinal cords from PV-infected transgenic mice. A sensitive, EV-specific, seminested RT-PCR assay was used to detect EV genome in RNA extracted from the specimens and controls.


RESULTS
The assay detected EV RNA in a 10(-5) dilution of infected mouse tissue. EV RNA was not detected in the ALS specimens or in specimens from control cases, despite the presence of amplifiable RNA as assessed by amplification with control primers, whereas all of the positive control specimens yielded the expected PV amplification product.


CONCLUSIONS
The reported association between EV infection and ALS was not confirmed by testing this set of specimens with these sensitive methods.
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W A
WA
Respiratory and Enteric Viruses Branch, Division of Viral and Rickettsial Diseases, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
Berger
M M
MM
Oberste
M S
MS
Brooks
B R
BR
McKenna-Yasek
D M
DM
Brown
R H
RH
Roos
R P
RP
Pallansch
M A
MA
D020121:5' Untranslated Regions / Q000235:genetics; D000690:Amyotrophic Lateral Sclerosis / Q000821:virology*; D000818:Animals; D036022:Capsid Proteins / Q000235:genetics; D004770:Enterovirus / Q000235:genetics / Q000302:isolation & purification*; D005189:False Positive Reactions; D005615:Freezing; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D017955:Poliovirus / Q000235:genetics / Q000302:isolation & purification; D012367:RNA, Viral / Q000032:analysis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D013116:Spinal Cord / Q000737:chemistry / Q000821:virology*
D020121:5' Untranslated Regions; D036022:Capsid Proteins; D012367:RNA, Viral