Addition of anti–TGF-β antibody results in reduced expression of mMCP-1. mBMMC were grown in WEHI/rrSCF for 7 days before transferring them in duplicate to 48-well plates supplemented with rhTGF-β₁ (100 pg/mL)/rmIL-9 (5 ng/mL)/WEHI (15%)/rrSCF (50 ng/mL) (T/I/W/S ) or with rmIL-9/WEHI/rrSCF (I/W/S) or WEHI/rrSCF (W/S) at the same concentrations. To these cultures were also added chicken anti–TGF-β at 1 μg/mL (□) or 10 μg/mL (▩), or chicken IgG control at 1 μg/mL (▪) or 10 μg/mL (▨). The mean percentages of mMCP-1⁺ mast cells were assessed by immunohistochemical staining of cytosmears with MoAb RF 6.1 48 hours after addition of the cytokines and antibodies (n = 2).