Figure S1.

Identification of CD49e as a CAF-specific cell surface marker. (A) We performed HT-FC with panel of 363 antibodies on four CAF lines and five HGSOC patient samples. Patient samples were costained with CD45 and CD31 to exclude inflammatory and endothelial cells from the analysis. A heatmap of the percentage of positive cells for each antibody on CAFs and the CD45⁻CD31⁻ fraction of tumor samples was generated using unsupervised hierarchical clustering with a Pearson correlation distance metric and complete linkage. A cluster of differentially expressed markers was found, of which CD49e was the top hit (red arrow). (B) Representative FACS plots of CAFs (left) and a primary HGSOC sample (right) stained for CD49e. The gate for CD49e expression was set based on a fluorescence-minus-one (FMO) control. (C) A tissue microarray containing tissues from nine different types of cancer was stained for CD49e (green) and pan-cytokeratin (CK; red). Cores were scored based on stromal specificity (i.e., staining was exclusive to stroma, or it also stained tumor cells) and on stromal staining pattern (i.e., the stroma was broadly stained, or only a subset of stroma was stained). The data were compiled into a table (left), and representative images are shown (right). Scale bar = 100 µm. FSC-A, forward scatter area; FSC-H, forward scatter height; FSC-W, forward scatter width; SSC-H, side scatter height; SSC-W, side scatter width; ccRCC, clear cell renal cell carcinoma; HN, head and neck.