Figure 1.

TILs and α-SMA⁺ CAFs in tissues. 1) A, HE staining showing the extensive presence of lymphocytes around ductal breast carcinoma in situ (red arrow), which was rarely found in normal tissue (white arrow area). B, C: CD3⁺ TIL mainly distributed in the stroma of ductal breast carcinoma and invasive breast cancer. 2) D showing Foxp3⁺Tregs (green) mixed with α-SMA⁺ CAFs (red) in cancer stroma (red arrow area). Tregs was scarce in normal stroma (white arrow area). 3) α-SMA⁺ fibroblasts (CAFs) only appeared in the stroma of breast cancer (E). All fibroblasts showed α-SMA negative and vimentin positive (red) in the stroma around breast ducts and acini (F). The green α-SMA⁺ cells around breast ducts and acini represent myoepithelium (vimentin negative). A, B, 65-fold; C, D, E, F 100-fold.