Immunolocalization of hornerin expression in breast tissue. (A) Reduction mammoplasty tissue sections were subjected to immunohistochemical analysis using a hornerin specific antibody or corresponding negative control. A minimum of 10 patient samples were analyzed. Yellow bar = 200 μM, red bar = 50 μM. (B) Western blot analysis of hornerin expression in primary breast fibroblast and epithelial cell whole cell lysates isolated from reduction mammoplasty tissue samples. A minimum of five patient samples were analyzed per cell type. Representative data from five breast fibroblasts and three breast epithelial samples are shown. (C) Western blot analysis of exosomes isolated from primary breast fibroblast and epithelial cell cultures and representative TEM image of purified exosomes 30,000X. FB = fibroblasts, Epi = epithelial cells.