The ImmunoAtlas and Abcam teams have collaborated and designed a panel of seven antibodies (α-CD8α, α-Foxp3, α-Granzyme B, α-PD-L1, α-PD-1, α-Cytokeratin, α-EpCAM; Abcam), which mark several phenotypes essential to immunotherapy responses. The panel enables the identification and quantification of different immune subpopulations such as cytotoxic T-cells, regulatory T cells, etc within the tumor microenvironment. Breast cancer tissue array samples from 70 patients (normal, stage I to III) were stained with the markers (refer table) and multiplex IHC kit (Opal). All the images were acquired using a multispectral imaging system (Vectra® Polaris™).