The effect of interleukin‐10 and transforming growth factor β‐1 on HLA‐DR expression in colonic epithelial cells
Zimmerman MJ., Radford-Smith GR., Jewell DP.
The aim of this study was to assess whether interleukin‐10 (IL‐10) and/or transforming growth factor β‐1 (TGF β1) downregulate HLA‐DR expression using the HT29 cell line as a model of colonic epithelial cells. HLA‐DR expression was induced in HT29 cells with γ‐interferon. The effects of IL‐10 alone, TGF β1 alone, and IL‐10 and TGF β1 in combination were studied. HLA‐DR expression was assessed using flow cytometric analysis. γ‐Interferon induced HLA‐DR expression in a dose‐dependent fashion. In the absence of γ‐interferon, neither IL‐10 nor TGF β1 induced HLA‐DR expression. In isolation, neither IL10 nor TGF β1 downregulated HLA‐DR expression. When IL‐10 and TGF β1 were added in combination, small (6‐30%) statistically significant reductions in HLA‐DR expression were seen. The biological significance is unclear.