Ag NWs produce giant foreign body macrophages in BALF. Cells recovered from BALF at Days 1 (left), 7 (middle), and 21 (right) post exposure to sham control (A-C), S-Ag NWs (D-F), or L-Ag NWs (G-I). All panels are Brightfield microscopy images of cells from rats given a single instillation of sham control or Ag NW suspension at 1.0 mL/kg. BAL cells were stained with autometallography and toluidine blue counter-stain. Arrows indicate Ag NWs. Scale bar is 25 μm.