Figure 6.

Deletion of Smad3 in the recipient inhibits MMT in mouse chronic renal allograft rejection. Kidney allografts were transplanted into Smad3 WT or Smad3 KO recipient mice and examined 28 days later. (A) Immunofluorescence shows many F4/80⁺ α-SMA⁺ MMT cells in renal allografts from Smad3 WT recipients. This was substantially inhibited in Smad3 KO recipients. (B) Three-color confocal microscopy identifies MMT cells in an allograft from a Smad3 WT recipient on the basis of coexpression of F4/80 (green), α-SMA (red), and collagen I (blue) as indicated by arrows. (C) Z-stack image shows collagen-producing MMT cells, which is also further illustrated in the Supplemental Material. Note that a CD68⁺α-SMA⁺ collagen I⁺ MMT cell is indicated by arrow. (D) Quantitative data for counting of the F4/80⁺, α-SMA⁺, and F4/80⁺α-SMA⁺ cell populations. Data are mean±SEM for groups of 6–8 mice. ^##P<0.01, ^###P<0.001 versus Smad3 WT mice.