The effects of cyclosporine on HILDA/LIF gene expression in human T cells.

We examined the effect of cyclosporine on HILDA/LIF gene expression in alloreactive human T lymphocyte clones (ATLCs) 2B11 and 2F7 obtained from cells infiltrating a rejected human kidney graft. Both ATLCs were stimulated either by the specific antigen or by PMA + calcium ionophore in the presence of various concentrations of CsA (10-500 ng/ml). Inhibition of HILDA/LIF gene expression was analyzed at the protein level using a proliferative assay on the HILDA/LIF-dependent Da-1a cell line and by RNA blotting using a specific probe. Without CsA, the kinetics of mRNA accumulation for both ATLCs peaked at 5 and 10 hr, respectively, after mitogenic and antigenic stimulations. HILDA/LIF activity peaked at 24 and 72 hr, respectively, after mitogenic and antigenic stimulation in supernatants from both ATLCs and decreased thereafter. Subsequent experiments with CsA were thus performed at these time points. Our results show that HILDA/LIF mRNA accumulation and protein secretion in 2B11 and 2F7 clones were strongly inhibited in a dose-dependent manner by CsA, in both stimulation conditions. Maximal inhibition of HILDA/LIF transcripts and protein secretion (60-90%) was observed within the range of 75-500 ng/ml CsA.