The CC chemokine thymus- and activation-regulated chemokine (TARC/CCL17) acts on CC chemokine receptor 4 (CCR4), which is known to be selectively expressed in Th2 cells. In order to compare the regulatory profiles of TARC production by tumor necrosis factor-α (TNF-α), IFN-γ, interleukin-4 (IL-4) and IL-13 in keratinocytes and fibroblasts, HaCaT cells, a human keratinocyte cell line, and NG1RGB cells, a human skin fibroblast cell line, were used. The expression of TARC protein was measured using enzyme-linked immunosorbent assay (ELISA), and the mRNA level was detected by reverse transcriptase polymerase chain reaction (RT-PCR). The spontaneous expression of TARC protein and mRNA levels were augmented by TNF-α and IFN-γ and were inhibited by IL-4 and IL-13 in the keratinocytes. The fibroblasts expressed the TARC protein and mRNA only in the presence of IL-4+TNF-α or IL-13+TNF-α stimulation. IFN-γ further enhanced the IL-4+TNF-α or IL-13+TNF-α-induced TARC production in the fibroblasts. Thus, TNF-α and IFN-γ -induced TARC production was differentially regulated by IL-4 and IL-13 in human keratinocytes and fibroblasts.
All Science Journal Classification (ASJC) codes
- Molecular Biology