IL34 and psoriasis: In contrast, total skin transcriptome of Treg-specific cytokine that mediates immune tolerance [IL34 (35–37)], an anti-inflammatory cytokine that inhibits innate immune signaling [IL37 (38, 39)], and KC stem cell marker of quiescence [KRT15 (40)] were increased in posttreatment psoriasis lesional skin compared to pretreatment psoriasis lesional skin in both microarray and RT-PCR experiments, albeit the decreased T-cell, DC, and KC numbers (Figures 2B, C, p < 0.05).