(a) Immunohistochemistry and (b) immunofluorescence double staining: Representative image of CD4 (red)/CD8 (blue) (top) expression and Foxp3 (FITC)/CD4 (Cy3) (bottom) expression in liver metastases on day 10 (n = 7) compared to increased CD4 (red)/CD8 (blue) expression and Foxp3 (FITC)/CD4 (Cy3) expression on day 20. Immunohistochemistry: Nova red brick red color, Vector Blue blue color. Haemalaun blue color-nuclear counterstaining. Asterisk with indication lines show metastases next to normal tissue (×100 and ×400). Immunofluorescence: FITC green fluorescein isothiocyanate, Cy3 red and DAPI 4',6-diamidino-2-phenylindole blue - nuclear counterstaining (×250).