Table 1.
Composition of stool specimen collection used for parallel testing by poliovirus serotype and genotype determined prior by virus isolation, ITD and sequencing.
Fig 1.
Schematic of poliovirus cellular attachment and the principle of soluble recombinant PVR-His enrichment.
(A) Poliovirus attaches to cell bound PVR during natural infection. (B) Binding of soluble recombinant PVR-histidine and poliovirus. (C) Capture of PVR-histidine with nickel-agarose solution and pelleting of the PVR-His/poliovirus nickel agarose complex through centrifugation, removal of supernatant, and downstream application.
Table 2.
Development of the PVR-His protein capture assay using different concentrations of nickel agarose and PVR-His protein.
Fold change of mean RNA copy numbers with PVR-His capture (enrichment step) were compared to extracted RNA without PVR-His. P-values were calculated by t-test. Quantitative RT-PCR was performed using 1 μL template RNA.
Table 3.
Development of the PVR-His protein capture assay using different concentrations of PVR-His protein and PEG buffer.
Fold change of mean RNA copy numbers with PVR-His capture (enrichment step) in PEG buffer were compared to extracted RNA without PVR-His addition. P-values were calculated by t-test. Quantitative RT-PCR was performed using 10 μL template RNA.
Table 4.
Comparison of virus isolation and the PVR-His protein capture method on limiting dilutions of PV1-positive stools.
The lowest titer of poliovirus by culture and the lowest titer of poliovirus detectable by the PVR-His capture assay is listed.
Table 5.
Two-by-two table comparison of poliovirus detection in the culture-independent detection method (PVR-His capture) followed by RNA extraction and standard virus isolation.
Results from a total of 182 stool specimens are shown that were selected on the results from previous testing for poliovirus in virus isolation, ITD PCR, and VP1 sequencing (Table 1).
Fig 2.
Parallel testing assay-by-assay results for PV-positive stools.
Poliovirus RNA was extracted after PVR-His enrichment and screened in ITD real-time RT-PCR for all samples. CT values are shown by ITD assay and when positive in PVR-His enrichment/RNA extraction but negative in virus isolation.