Question:
The positive control was produced for coating ELISA plates (Ab detection) or for inoculation for Ab production and so it was never titered. However, if I look at the titration curves for the PC and the titered H9N2 and compare similar absorbance values, the value for the neat PC (1.742) is the same as 100,000 EID50/ml for H9N2 (1.739). A 10-fold dilution of H9N2 (10,000 EID50/ml) results in an absorbance of 0.276. An 8-fold dilution of the PC results in an absorbance of 0.299. So you could ballpark the PC as ~100,000 EID50/ml.
Resolution:
