Figure 3.

S. aureus leads to the rapid induction of proinflammatory cytokine gene expression. Adult Lewis rats were implanted with S. aureus-containing or sterile beads. Tissues were collected from the lesion site of individual animals at the indicated time points for RNA extraction. A total of 5 μg of RNA from S. aureus or sterile bead implanted tissues was used in RPA with ³³P-labeled ribroprobe templates. Controls included yeast tRNA and normal Lewis rat brain RNA. The housekeeping genes L32 and GAPDH serve as internal controls for the assay. The identity of RNase-protected bands in the experimental samples are determined by plotting a standard curve of the migration distance versus log nucleotide length of the undigested probes (not shown). The size of experimental mRNAs are extrapolated from this standard curve and are denoted at the left.