Fig. 1

Prostein immunostaining of normal tissues. Prostein staining was always granular, cytoplasmic and predominantly perinuclear (“endoplasmatic reticulum pattern”). The panels show a particularly strong prostein staining of acinar cells of the prostate (A) while the staining is less intense in surface epithelium of the stomach (B). An even weaker prostein positivity (not always involving all samples and all cells) can also be seen in colorectal epithelium (C), pancreatic islet cells (D), epithelial cells of the adenohypophysis (E), respiratory epithelium of the lung (F), and in glia cells of the brain (G). An intense perinuclear prostein staining also occurs in a subset of monocytic cells of the spleen (H)