Radial inhibition assay results demonstrating the effect of innate immune molecules on otitis media pathogens. Representative radial inhibition assay for the measurement of the activity of innate immune molecules against NTHi 12, M. catarrhalis 035E (M cat), S. pneumoniae 3 (Sp 3) and S. pneumoniae 6B (Sp 6B). Panel A shows the results of testing three doses (50 μg, 100 μg and 200 μg) of human lysozyme (Lz) against the bacteria. Panel B shows the results of testing the lactoferrin (Lf) and the defensins against the bacteria. Three doses (4 μg, 10 μg and 40 μg) of human lactoferrin (Lf) were tested, as were two doses (4 μg and 10 μg) each of human β defensin-1 (hBD-1) and β defensin-2 (hBD-2). Each dose was delivered in a total volume of 4 μl. The control well received only solvent (0.01% acetic acid). The diameter of the inhibition zone was measured and averaged in three separate experiments.