Gene expression profile of human epidermal keratinocytes in response to IFNgamma, IL-4, IL-6, IL-17A and IL-22

To understand the role of epidermal keratinocytes in immunopathology of skin diseases with predominant T helper (Th) cell responses, we measured the genome-wide transcriptional profile of human keratinocytes in response to IFNgamma, IL-4, IL-17A or IL-22, major cytokines produced by Th1, Th2, Th17 or Th22 cells, respectively. IL-6 was also included in the transcriptional profile analysis because a variety of pro-inflammatory stimuli stimulate human keratinocytes to produce IL-6 that has an autocrine or paracrine role in epidermal immunity. We aimed to discover commonly expressed genes in human keratinocytes in response to pro-inflammatory cytokines, which would be associated with common pathophysiological responses in various skin diseases such as skin permeability barrier disruption or epidermal hyperplasia. Normal human keratinocytes (NHKs) were stimulated with IFNγ, IL-4, IL-6, IL-17A and IL-22 for 24 hours and harvested for total RNA extraction and hybridization on Affymetrix microarrays.