To substantiate the data derived from FACS analyses, IHC was performed to detect immune cell infiltration into tumors by staining for immune cell type-specific markers: pan-immune cells (CD45), tumor-infiltrating lymphocytes (TIL, CD8), neutrophils (MPO), and M1 and M2 macrophages (Nos2 and Arg1, respectively). The gene discussed is NOS2; the disease is neoplasm.