Figure 4

MFB-F11 cells can measure biologically active TGF-β and TGF-βs from various sources and species. MFB-F11 cells (4 × 10⁴ cells/well) were incubated with 100 μl diluted (1: 100) mouse serum (A), McA-7777RH cell culture supernatant (B) or diluted (1:50) mouse brain extract (C) which were either not activated (NA) or activated with acid (AA). Activated medium was incubated with a pan-specific TGF-β neutralizing antibody (AA + 1D11) or left untreated (AA). D: 4 × 10⁴ MFB-F11 cells/well were left untreated or co-cultured with 4 × 10⁴ McA-7777RH cells/well. SEAP activity was measured after 24 h as described in Figure 2. Bars represent mean ± SEM of triplicate wells from 1 representative experiment. Note the logarithmic scale in A and C.