However, these quantitative categories alone do not adequately reflect the deeply complex immune infiltrate that is typically observed in human tumor tissue: besides infiltration with CD4+ T helper and CD8+ cytotoxic T cells, many tumors contain abundant immune suppressive cell types, like myeloid derived suppressor cells (MDSC), M2 macrophages and regulatory T cells (TREG cells)17. Here, CD8A is linked to neoplasm.