Figure 9. Antibacterial activity of extract from organotypic epidermal cultures.

CFU assays using E. coli (A) and S. aureus (B) as targets were performed with extract from epidermal cultures and are displayed here as bacterial survival compared with control samples incubated with buffer alone. As expected, there was no difference in the killing of E. coli with nonstimulated epidermal cultures and TGF-α–stimulated epidermal cultures (P = 0.4, n = 3). In contrast, there was a significant difference in the killing of S. aureus between nonstimulated epidermal cultures and TGF-α–stimulated epidermal cultures (P < 0.041, n = 5). Nonstimulated epidermal cultures did not cause significant killing of S. aureus compared with buffer alone (P = 0.77, n = 5). Mean and standard deviation are shown.