highly significantP < 0.0001
This IFN had greater activity on monkey and bovine cells than the IFN from Con A-induced supernatants, although it did not show the same cross-reactivity as TABLE II Summary of IFN Characterization Type of sample Mean percent reduction of ti- Number ter -4- SD after treatment with of sam- ples Antiserum to tested a-IFN pH 2 Con A-stimulated PBM supernatant 15 21 :tz21" 97 + 3 Influenza virus-stimulated PBM super- 20 77 +- 18" 95 ::t:3 natant a control 9 95 - 8 11 -+ 13 * The difference between these two groups was found to be highly significant by the Wilcoxon two-sample rank sum test (P < 0.0001).