Confocal analysis of BMP4 and F4/80 colocalization in spleen macrophages. For immunofluorescence procedure, spleen sections of control mice (A) and Z9Epo1 (B-C) mice were stained with both anti-BMP4 and anti-F4/80 antibodies followed by an Alexa 488–conjugated goat anti–rabbit (BMP4; green) and an Alexa 555–conjugated goat anti–rat (F4/80; red). (C) The merge between the green and the red fluorescence at 2 different magnifications reveals yellow color corresponding to colocalization of F4/80 with BMP4 protein in a Z9Epo1 mouse. Most BMP4⁺ cells appear to be F4/80-expressing cells. At least 3 independent spleens were analyzed in each condition. Scale bar represents 10 μm.