FIG 4.

Identification of protein antigens recognized by sera from vaccinated mice. (A) Immunoblots of S. pneumoniae TIGR4, D39, or 19A strain whole-cell lysates probed with serum diluted 1:1,000 from mice vaccinated with either HKL or MAV. The numbers on the left are molecular masses (in kilodaltons). (B) Identification of protein antigens recognized by sera from vaccinated mice using the MSD assay. Values are normalized to those for the negative control consisting of buffer-vaccinated mouse serum. Mean values are shown, with error bars representing standard deviations for sera from mice vaccinated with MAV (n = 3, black columns) and a mouse vaccinated with HKL (n = 1, gray columns).