IL17A and periodontitis: Quantitative real-time PCR (qPCR) of RNA extracted from the palatal gingiva of aged WT mice with naturally occurring periodontitis showed that all macrolides tested significantly upregulated the gene expression of Del1 and anti-inflammatory gene, Il10. Macrolides suppressed the expression of pro-inflammatory genes Il17 and Il1b (Figure 2D, upper panel).