Figure 1.
The sensitivity of the double antibody sandwich ELISA using different capture and detection MAbs pairs.
The detection of NS1 in culture supernatants of WNV-infected cells by different MAb pairs. The culture supernatants of WNV-infected cells were serially diluted 2-fold. Data points represent the mean ± standard deviation from three replicates. The most effective pairs were determined by the highest dilution of the OD450 values.
Table 1.
Characteristics of MAbs against the NS1 protein of WNV.
Figure 2.
Evaluation of the sensitivity and specificity of the rWNV-NS1 antigen-capture ELISA.
A, The NS1 standard curve as determined by the purified rWNV-NS1 antigen-capture ELISA. Various concentrations of WNV-NS1 and DENV1-4-NS1 proteins were analysed. BSA was used to establish the baseline. B, The detection of NS1 in WNV-infected cell culture supernatants and other closely related members of the flavivirus family, DENV, JEV, YFV, and TBEV, by the NS1 antigen-capture ELISA. Two-fold serially diluted supernatants from WNV-, four DENV serotype-, JEV-, YFV-, or TBEV-infected cells were subjected to the WNV-NS1 antigen-capture ELISA. Data points represent the mean ± standard deviation from three replicates. The cut-off value was set at twice the average value of the negative controls from three replicates. Positive OD450 values were only observed for the WNV-NS1 protein and WNV-infected cell supernatants.
Figure 3.
The detection of NS1 in WNV-infected mice sera by the NS1 antigen-capture ELISA.
The data represent the OD450 of the serum samples at 1∶100 dilution. The dashed line represents the cut-off value, which is twice the mean value of the negative control. Each data point represents the mean OD450 of duplicate assays. The results were considered positive if a sample yielded an OD450 above the cut-off value. The cut-off value was set as twice the mean value of the negative control. Each data point represents the mean OD450 of duplicate assays.
Table 2.
Comparison of the sensitivities of the WNV-NS1 ELISA and real-time RT-PCR for the detection of WNV-infected mice serum samples.