Figure 1

Examples of CD4 ⁺ , FOXP3 ⁺ and IL-17 ⁺ infiltrating lymphocytes in ductal and lobular breast cancer. A, B, C: Immunohistochemical staining of breast cancer tissue punches incubated with anti-CD4 antibody (brown staining): A: Ductal breast cancer with predominantly stromal and intratumoral CD4⁺ cells. B: Ductal breast cancer with prominent cell pleomorphism and easily detectable intratumoral CD4⁺ cells, within the tumor and surrounding it. C: Example of an invasive lobular breast cancer with CD4⁺ cells. D; E: Zoom of breast cancers incubated with anti-FOXP3 antibody (brown staining): D: Invasive ductal breast cancer with clear intratumoral infiltration by FOXP3⁺ cells. E: Invasive lobular breast cancer with stromal and intratumoral FOXP3⁺ cells. F: Ductal breast cancer showing a single infiltrating IL-17⁺ cell (brown staining). G/H: Ductal carcinoma with a FOXP3/CD4 ratio > 1. G shows the FOXP3 staining and H the CD4 staining. I/J: Lobular cancer with a FOXP3/CD4 ratio < 1. I shows the FOXP3 staining and J the CD4 staining.