Figure 2.

CD47 protein is expressed in the endocrine and exocrine compartments of human pancreata. Human pancreas tissue sections were costained for insulin and CD47 (A), TSP1 (B), or SIRPα (C). Confocal images were taken at ×10 and ×20 magnification with tile scanning. Enlarged images in the boxed areas are shown on the right. Quantification of the fluorescence intensity relative to the negative control (secondary antibody only staining) was analyzed for islets (D) or nonislet areas (E) using ImageJ software. One slide from each donor organ (total of 3 donors) was examined. Three to four separate areas of the tissue sample were characterized for each slide. Five or more islets were counted in each area. The scale bar in tile scanning images equals 100 µm and in enlarged images equals 50 µm. Human pancreas tissue sections from a single donor (Hu1172) were costained for TSP1, CD47, and SIRPα and confocal images were acquired at ×40 magnification and are shown on the far right of each panel (F). Images at ×40 magnification from tissue samples from 3 donors were quantified for protein expression in acinar and ductal cells (G). Data are presented as the means ± SD. Each dot represents an islet or the nonislet area of each donor tissue section. SIRPα, signal regulatory protein α; TSP1, thrombospondin-1.