TEC expression of c-Met and the effect of HGF treatment. The HGF receptor c-Met is expressed by TECs and HGF treatment reduces TEC injury. Top row: BDF1 (Ly5.2) recipients were treated as described in the Figure 4 legend. On day 14 after GVHD induction, thymic tissue sections from the 3 groups that received transplants were analyzed for histology with the use of hematoxylin and eosin (HE) stain. M indicates medulla; and C, cortex. Middle row: On day 14 after GVHD induction, thymic tissue sections from the 3 groups that received transplants were analyzed for the expression of HGF receptor c-Met with the use of an anti–c-Met antibody. Adjacent sections (not shown) were stained for cytokeratin to verify the presence of TECs. Bottom row: On day 14 after GVHD induction, thymic tissue sections from the 3 groups that received transplants were analyzed for medullary TECs with the use of an anti-MTS10 antibody. Original magnification × 200 (indicated in parentheses). Image acquired using a dual-model cooled CCD camera C4880 (Hamamatsu Photonics, Hamamatsu, Japan), numerical aperture 0.75, and ARGUS (Hamamatsu Photonics).