Effects of recombinant NK4 and hepatocyte growth factor on CD4+ T cells. CD11c+ dendritic cells from C57BL/6 mice were incubated in the presence or absence of hepatocyte growth factor or NK4 for 24 h. After thrice washing with Hanks' balanced salt solution (HBSS), dendritic cells (H-2b; 1 × 106 cells/ml/well) were irradiated (20 Gy) and cocultured with CD4+ T cells from SKG mice (H-2d; 4 × 106 cells/ml/well) in 24-well flat-bottomed plates. After 72 h, viable cells were harvested, and, after thrice washing with HBSS, the cells (1 × 105 cells/200 μl/well) were stimulated in 96-well flat-bottomed plates coated with 5 μg/ml anti-mouse CD3 monoclonal antibody. The concentrations of interferon γ (IFN-γ) (A), interleukin 4 (IL-4) (B) and IL-17 (C) in the culture supernatants were measured by enzyme-linked immunosorbent assay. Data represent the means ± SD of three independent experiments. *P < 0.01. NS, not significant.