FIG. 2.

Intranasal administration of PIKA induced the production of proinflammatory cytokines. Groups of three BALB/c mice each were given either 100 μg of PIKA i.n. in PBS or 50 μl of PBS alone and were sacrificed 24 or 72 h later. The lungs were stored at −80°C until all samples were collected and homogenized in 1 ml of RPMI 1640 medium. To measure the concentrations of various cytokines, 50 μl of clarified samples was tested in duplicate using the Bio-plex protein array system. The concentration of each cytokine detected in the PIKA-treated group is expressed as the fold increase over the concentration detected in the PBS-treated group. The bars and error bars represent the means and standard errors for each group. Note that, due to the differences in the expression levels of the various cytokines, the scales of the y axes are different. These data are representative of two independent experiments. The absolute values of the cytokines in this experiment can be found in Table S1 in the supplemental material.