Microarray analysis of infiltrating cells identifies the expression of the chemokine receptor CCR10 to be elevated in the α7KO. A) RNA collected from infiltrating cells from croton oil treated ears was analyzed using SABiosciences arrays. As indicated, the DeltaCt (cycle number to detect transcript after normalization to (β-actin and GAPDH) is inversely related to transcript number. The central line is the linear regression best fit (R2 = 0.95) and flanking dotted lines define the boundaries of statistical significance (p > 0.05). Individual error bars reflect ± the standard deviation. Transcripts that are different in expression between the α7WT and α7KO are boxed and their identity (CCR10, IL1f8 and CCl20) shown. Some additional transcripts that failed statistical significance are also identified. B) RT-PCR analysis (see Methods) of transcripts identified by microarray using Taqman gene expression. There is a good qualitative match with the microarray data. C) A similar analysis of the total ear skin depleted of infiltrating cells revealed no detectable changes in transcript expression that were confirmed by RT-PCR. Analyses for transcripts not on the array such as CCL27 and CCL28 (the ligands for CCR10) present in resident cells of the ear skin were included (* p < 0.01). Neither CCL27 nor CCL28 were detectable in infiltrating cells (not shown).