The local inflammatory response to croton oil is enhanced in the α7KO mouse. Ears of WT and α7KO mice (5 animals/experiment) were treated with croton oil. Six hours post-treatment ears were removed, dorsal and ventral halves separated before floating them dermis side down on media overnight. A) Total number of cells isolated per treatment group was then measured (99% viability, not shown). The light grey bars represent WT mice and dark grey bars the α7KO. Error bars reflect ± of the standard error of the mean of all experiments (3-5 experiments per group); * p < 0.05 and **, p < 0.01 (two-tailed Student's T-test). B) Expression of key pro-inflammatory cytokine transcripts from infiltrating cells using qPCR (Methods). The average fold increase normalized to a value of 1 for IL-1β, IL-6 and TNFα from α7WT mice (light grey) and α7KO (grey bars) are compared. Error bars reflect the standard error of the mean from 3 independent experiments with 5-6 mice per experimental group. C) Analysis of transcripts from ear skin after removal of infiltrating cells from untreated mice, or mice treated with croton oil. The expression of these cytokines does not differ between α7WT and α7KO. Light gray bars represent ear skin from WT mice and dark gray for α7KO mice. Non-shaded bars represent ear skin from untreated WT mice. Ear skin RNA amounts recovered did not differ between genotypes (not shown).